Technology in Construction
Lasers
Once the stuff of science fiction and Star Wars movies, lasers have moved into the mainstream and taken their place in consumer electronics, in doctors’ offices, and even on construction sites. The same laser beam that causes a CD player to produce music and allows an eye surgeon to restore a patient’s 20-20 vision in a matter of moments can help a bulldozer operator make fast and accurate work of a grading or excavating assignment.
“If you’re trying to achieve a perfectly flat grade, a laser is absolutely best for that,” says Boyd Reynolds, product marketing manager for Leica Geosystems. “And if you’re trying to achieve a grade that’s sloped, a laser is perfect. It provides wonderful accuracy.”
Indeed, most lasers boast an accuracy to one-thirty-second of an inch.
“Professional construction lasers deliver very tight accuracy,” says Pat Bohle, division vice president of marketing for Trimble’s construction division. “That’s especially important for applications such as concrete pad work for large commercial buildings, which typically have very tight tolerances.” While general and concrete contractors commonly rely on construction lasers and receivers for elevation control, he continues, they’re also ideal for use on smaller machines such as backhoes, skid-steers, and mini excavators for site preparation applications.
“The use of lasers for these applications is less adopted,” he notes. “However, they do provide significant productivity improvements and tight accuracy control for a range of dirt-moving applications.”
But what is a laser and how does it work? The word laser is an acronym for “light amplification by stimulated emission of radiation.” A laser is a specific kind of light, the qualities of which make it ideal for construction purposes. Laser light, for example, is monochromatic. It contains one specific color that is easy to recognize. In addition, laser light is highly directional. Light from most sources spreads out as it travels, so as the distance from the source increases the amount of light hitting any given area actually decreases. Laser light, however, has a very tight beam that remains strong and concentrated over a distance as much as 2,500 feet long. Think about a flashlight, which releases light in many directions. The beam becomes weak and diffused. Laser light travels as a parallel beam and spreads very little.
For grading applications, the rotating construction laser is the tool of choice. Think of it as a high-tech level that emits one or more light beams through its apertures to create a level reference plane. The laser box, from which the beam originates, sits on a tripod, and as the beacon rotates, it expands the level plane to cover a 360-degree-diameter range.
Rotating lasers come in three basic types: flat plane, single slope (also called single grade), and dual slope (also called dual grade). Most are self-leveling, which means you take it out of the box and set it on a tripod and it automatically finds and maintains level within a specified range. Manual level lasers, which require the operator to adjust the unit by hand using thumb screws and bubble vials, also exist, but over the last five years most have given way to electronic models that require only rough leveling upon setup.
A flat-plane laser emits a single horizontal beam from its rotating beacon. The beam varies in distance, generally ranging from 500 to 1,500 feet. It is commonly used for checking elevation and setting foundations and concrete.
A single-slope laser allows the operator to dial in one axis of a slope. It might be used for any general construction application, including excavation and sloped pads. A farmer might use a single-slope laser, for example, to grade a hog pen in which he wants everything to fall to one corner. The distance range for single-slope laser beams is similar to that of flat-plane lasers.
With dual-slope lasers, the beacon emits simultaneous horizontal and vertical beams to establish both level and plumb reference lines. The surface can be flat or tilted with a grade. A dual-slope laser has a distance range of 1,000 to 2,500 feet.
So how, exactly, does a laser—whether flat plane, single slope, or dual slope—function on the construction site? A construction laser consists of the laser beacon itself, which produces the beam of light, and a receiver that registers the beam and lets the bulldozer operator know whether or not he’s on target. The laser beacon sits atop a tripod strategically located on the construction site. The receiver is attached to the appropriate part of the equipment—say, the blade of the bulldozer. It is situated on a measuring rod, which allows the operator to place the blade properly in relation to the site’s benchmark. The benchmark determined by the surveyor and project designer indicates the height, width, and length of the area being graded.
“All construction sites have a benchmark,” says Rob Roske, owner of Montana Lasers LLC, “and usually there are two of them.”
The laser is set at some number of feet above the benchmark, and as the beam hits the receiver, which is adjusted on the measuring rod to the same number of feet above the benchmark, the receiver lets out a beep indicating whether the blade is too high, too low, or just right. There is no need for reading grade stakes or having a work partner tell the operator where or how much to adjust the blade.
In the pre-laser era, such work would have been accomplished with automatic or manual levels with two people on the job—one to operate the equipment and another to point out where the grade was—say, a tenth of an inch too high or maybe two-tenths of an inch too low.
“Now the receiver will let you know if you need to move the blade up or down,” says Roske.
Adds Bohle, “By providing tight elevation control for a range of tasks, a contractor can work more productively.”
As the laser rotates, it creates a plane of light and will register on a receiver operating anywhere within the circle. Every laser is rated by the manufacturer for a certain distance range, and the keys to accuracy are staying within that range and making sure nothing interferes with the flow of the beam.
Although a laser rated at, say, 1,500 feet can be detected by a receiver as far as 2,500 feet away, it won’t provide an accurate reading at such a distance. As the beam extends beyond its established rating, two things happen. First, the light begins to diffuse slightly and in doing so becomes less precise, and second, the curvature of the earth actually impedes the beam as it heads toward the receiver.
Construction experts agree that in determining which type of construction laser—flat plane, single slope, or dual slope—will meet his needs, a contractor should consider what he wants to accomplish with it.
“You need to know the applications, what you want to do with it,” says Reynolds. “Some lasers are more accurate than others; some reach farther than others. If you’re doing a lot of sports fields, for example, you’ll want a single-grade laser. More complex jobs require dual grade.”
If the potential for machine control is a consideration, look for a unit with a laser beacon that rotates at least 600 revolutions per minute. Some go as high as 900 revolutions per minute, but 600 is the minimum for machine control. In some models, the laser rotates only 300 revolutions per minute and while that may be fine when the operator controls the blade or bucket, when a contractor decides to step up to the next level and let machine control run the show, his 300-revolutions-per-minute laser will be too slow.
“The laser market has become fairly homogenous, and there’s not a lot of difference between competitors,” continues Reynolds. “It’s important, though, to key in on a dealer that will provide service. The laser will get knocked over, so you need to find a reputable dealer with good service.”
Construction lasers range in price from $500 to $800 for a flat-plane model, $1,000 to $1,600 for the single slope, and $6,000 to $7,200 for the dual slope. A contractor prepared to spend $800 on a flat-plane laser might do well to consider springing an extra few hundred dollars for the single-slope variety. According to grading professionals, the more complicated jobs he’ll be able to take on will more than make up the difference.
Coming up: Construction lasers and machine display and control—letting the equipment do all the work.
Pumps: An Introduction
Simply defined, a pump is a machine or device used to raise, compress, or transfer fluids from one place to another. Pumps come in different shapes, sizes, and designs and thus serve a variety of purposes on a construction site.
When a backhoe rolls forward on its tracks and scoops up a bucket of dirt, for example, a complex set of hydraulic systems makes each movement possible. At the center of the action are hydraulic pumps, which, in this case, provide the flow of pressurized oil the various systems need in order to function.
Here are five types of pumps commonly used on construction sites and heavy equipment:
Gear Pumps. Gear pumps generally are used to pump thick fluids such as oil. They consist of a pair of meshing gears that rotate in a housing. As the fluid moves into the inlet region, it is trapped between the gear teeth and carried around to the outlet side. The pressure in the outlet region builds up until it is high enough to discharge the fluid.
Piston Pumps. The basic piston pump consists of some number of pistons housed within individual cylinder barrels. As the pistons are pulled upward within the cylinder barrel, a vacuum is created that sucks fluid through an intake valve into the open space. When the pistons are pushed downward, the fluid is expelled through exit valves. The pumping rate can be adjusted by altering the distance the pistons retract within the cylinders. Doing so controls the amount of liquid discharged by each stroke. Piston pumps are commonly used on excavators and other heavy construction equipment.
Vane Pumps. Rotary vane pumps use rotating assemblies to move fluid within the pumping chamber. The vanes are mounted to a circular rotor that sits within a circular cavity. The centers of the circles are offset, and when the rotor spins, vanes are pushed outward. As the vane rotates along the intake side of the pump, the volume area increases and fluid is drawn into the vane chambers. Along the discharge side, the volume area decreases and fluid is forced out of the pump. Vane pumps have common applications on scrapers, conveyer belts, power steering, and automatic transmission.
Centrifugal Pumps. Centrifugal pumps move fluid by means of centrifugal force. Several ribs or vanes are mounted on a revolving disk within the assembly, and as the disks turn, they create suction, which pulls fluid into the pump. The fluid occupies the space between the vanes, and as it rotates with the blades, it is forced out through an exit valve. Centrifugal pumps often are used for pumping liquids for water supply systems, mines, irrigation, dredging, and sewage disposal.
Progressive Cavity Pumps. With a progressive cavity pump, fluid moves within a cavity that progresses along the pump. A rotor fits into the pump body, and as it turns, the cavity moves and fluid is sucked in to fill it. With continued rotation, the fluid travels through the cavity and out through the discharge. Cavity pumps are often used for sewage and cement applications.
Bidding and Estimating Software
In the old days of bidding and estimating, a contractor might have pulled out a pad of paper, a ruler, and a planometer to calculate the cost of a proposed job. He’d sharpen his pencil and write out the details by hand. He’d compute, either manually or with a calculator, the number of people he’d need to get the job done, how many hours they’d put into it, how much materials would cost, and what equipment would be required. An experienced contractor carried a lot of the information in his head—he’d done enough work over the years to make pretty accurate estimates.
Except when he didn’t.
A miscalculation—inadvertently counting as square feet what should have been square yards, actual costs of materials exceeding estimates—or any of a host of other errors could cost him big time, especially if he didn’t become aware of it until he was well into the project. Now, many computer-literate contractors use Microsoft Excel to complete estimates and plan out projects on spreadsheets. The possibility for error, however, is still high. Plug an incorrect formula or figure into one cell and the entire bid can be off.
Enter software designed especially for bidding, estimating, and project management. With products from companies such as Bid2Win, Constructw@re, and Corecon, contractors can stay on track from initial estimates to project completion. The software also allows them to streamline design and project management among team members throughout the life of the project.
“Bidding and estimating software allows a contractor to put together quantities and prices for a particular bid,” says Michael Gillum, director of research and development for Quest Solutions. His company produces six different software packages. “It could be for a pool, a house, a building, or a septic tank. The software allows it to be done much faster and more accurately because the computer is doing the math for you.”
Any contractor doing more than $1 million of work annually can benefit from some variety of the software.
“If someone digs out septic tanks and that’s all they do, they don’t need it,” continues Gillum. “If they do $1 million a year, though, and they want to stay competitive, they do.”
Software for bidding, estimating, and project management ranges in price from $1,000 to $20,000. Typically, the low-end programs will do measurements but won’t assist with pricing or anything else. At the high end are programs equipped with a host of bells and whistles that accommodate multi-users.
“A majority of businesses out there are under 30 employees,” says Norm Wendl, founder of Huntington Beach–based Corecon Technologies Inc. “Those people using Excel or Word for estimating and project management aren’t systematizing their work and aren’t able to truly track if they’re making money on certain activities for a job.”
Bidding, estimating, and project management software address the specific needs of professionals in the construction industry. It gives them a degree of standardization, so they don’t have to rely on a mix of spreadsheets and word processing documents to track their information. In addition, specific information is often built in so the contractor doesn’t have to research it himself. It might include, for example, the cost of concrete or lumber in the user’s area or the going price for labor or equipment use. The information on the database is updated on a weekly, monthly, or annual basis and based on figures specific to the user’s geographic area. Database companies such as RS Means and Construction Estimating Institute make the updates available via fax or an electronic spreadsheet the contractor can import into his existing database.
“The software will come with an average number for his area,” notes Gillum. “[The contractor] will add in his profit, travel time, the things that no software can predict.”
“A lot of businesses use Excel for estimating and QuickBooks for managing,” continues Wendl. “They may have a good business and may be making money at the end of the month, but the problem is they don’t know where they’re making money. On some bid items they’re making a lot, and on others they’re losing. With QuickBooks they can do accounts payable, timecards, payroll, et cetera, but it doesn’t give an accurate picture of which bid items are making an actual profit.”
Some applications, such as Bid2Win and Bid2Win Enterprise, Constructw@re, and Quest, a product of Quest Solutions, are independent software programs that are loaded onto a user’s computer. Corecon Technologies’ Corecon 2006 is a Web-based operation, which means users pay a monthly subscription fee and can access the software from remote locations using a secure login ID and password. Depending on the size of the business and the number of users, it can be more cost-effective than a self-contained software program a business owner would purchase outright.
“Corecon 3, our last Windows-based product, was $2,000 per user with a $400 annual maintenance fee,” says Wendl. “Corecon 4 and the second-generation Corecon 2006 ranges from $40 to $60 per user per month for a one-year contract.”
Some contractors would prefer to own their software program and customize it for their use. They’d rather not pay a monthly fee or deal with passwords and user names.
“Most contractors aren’t computer savvy,” says Gillum. “Often, this is the first time they’re using computers. A contractor who’s been in the business for 10, 20, or 30 years hasn’t been working on a computer. He wants to turn it on, walk through a few steps, and turn out a bid. It has to be easy and intuitive.”
On the bidding and estimating side, the software allows for detailed line-item estimates using industry-standard databases such as RS Means. It can track labor and equipment items, crews, materials, work assemblies, and formulas. To manage subcontractors, the software makes it possible to send out multiple bid requests, either electronically or via fax, and have subs and suppliers respond with their prices via the Internet. It can transform estimates into detailed prime contracts and estimate line items into subcontracts and purchase orders. Document control allows a general contractor to track, send, create, and customize requests for information, submittal packages, daily logs, and more.
For project management, the software assists the contractor in practically every aspect of running a job. First, it can automatically transfer the successful bid information to a project management file so the contractor doesn’t have to input for a second time all the data associated with the project. For day-to-day management, the software handles, among other tasks, document control, quality control, scheduling, job cost control, contract administration, project analysis, budgets, and even e-mailing and faxing reports. It will keep daily logs; track permits, specifications, and miscellaneous tests and inspections; maintain a project calendar; track equipment; maintain labor timecards; and manage all the details associated with subcontractors.
Applications such as Corecon 2006 have interface links to Microsoft Office, Microsoft Small Business Accounting, and QuickBooks so it can transfer project financial information, including project bills, invoices, timecards, and accounts payable and receivable, from one program to another.
Although software for estimating and bidding and project management has existed for 20 years, research shows that a full 50% of industry professionals still have not incorporated it into their business operations. For those who made the leap, however, business on average has enhanced ten-fold.
“Ten times more productivity is huge,” declares Gillum. “A guy who runs a bulldozer all day, goes home to his family, and then has to do estimates until 2 a.m. isn’t happy. But with the software doing so much of the work for him he can put out more bids, increase his productivity, grow his business, and spend more time with his family.”
IntroductionSome call it the biggest change in land development since the Industrial Revolution. They’re talking about the technology boom that is transforming the way design engineers, contractors, and job-site crews tackle their grading and excavation jobs. What used to be done manually can now be completed more efficiently and accurately with, say, a laser or global positioning system (GPS). Machine control systems like these and others bring a precision to the work site that contractors and equipment operators couldn’t fathom 10 years ago. No more waiting for a layout or grade staking to indicate how much dirt needs to be moved in a work area, and no more rolling repeatedly over a test strip to determine how many passes are necessary to attain the requisite compaction. Gone are the days of measurements taken by hand and operators relying on their judgment and experience to grade an area.
Likewise, equipment systems have taken a giant leap forward in recent years with electronically controlled fuel injection systems taking the place of carburetors, for example, and hydraulic valves operating by way of changes in electric current rather than a pushrod. And that’s just the beginning. The dozers of the future will resemble their predecessors about as much as a Ferrari does a Model A Ford.
Grading & Excavation Contractor is joining this 21st century construction revolution with a new regular section called Technology in Construction that will introduce, highlight, and examine the new technologies and systems. In these pages you’ll read about everything from equipment controls and systems that alter the way a backhoe or skip/load operator moves his machine to a host of software programs that help a contractor organize and manage all aspects of his business.
You’ll meet professionals in the field who share their experiences with the new technologies, explaining how they’ve incorporated them into their projects and how they’ve increased their productivity and improved their bottom lines. In the process, you’ll get ideas about how the new technology can help you improve and even expand your own business.
“We’re living history,” Topcon’s Richard Rybka says of the technology evolution. “You see people using it across the country from the Pacific Northwest to New England. It’s a massive progressive change.”
From lasers to construction management software, technology is creating a whole new world within the construction industry. New job opportunities are emerging for people ready catch this wave of the future. GPS specialists, for example, are finding themselves in high demand, as is the crew member who is well versed in data management, field operations, and how machinery works.
“It’s not only changing the way contractors do business but their responsibilities on the job site,” Rybka says of the technology that provides accurate, up-to-the-minute information that gives contractors a professional edge. “It’s really changing the contractor’s position on the ladder.”
There’s no doubt technology will continue to march forward and the construction professionals who take advantage of it will lead the industry. By featuring state-of-the-art machine controls, software programs, equipment systems, and more, Technology in Construction will help you stay at the head of the pack.
Machine Control
In the last few years a major change has swept over the world of construction equipment, and it can be summed up in two words: machine control. Machine control can take practically all of the guesswork out of grading and excavation by using laser, global positioning, and other advanced technology to set parameters and measurements otherwise done manually or with a trained eye.
Truly the wave of the future, machine control means as much to construction work now as the tractor did to farming almost 100 years ago.
Machine control consists mainly of laser and global positioning systems (GPS), machine interface systems, controls, and displays. To help acquaint readers with the technology that nearly all will encounter over the course of their professional lives, Technology in Construction will introduce the components, highlight their uses, and show how they come together in one piece of equipment. Descriptions and explanations will help readers build a basic understanding of how the elements work and how readers can incorporate them in their own construction jobs.
The goal of a grading and excavation job is to work a construction site with the appropriate equipment to achieve a design created by an engineer. Even if the job is a flat building pad, it usually has some slope. That slope can be created more efficiently and accurately than ever with the new technology. It might be a laser control system that provides two-dimensional control; it could be a robotic total station used for measuring angles and distances. Each of these, along with global positioning systems, calculate precise measurements and relay them to a display inside the cab.
Machine control systems fall into two categories: indicate and automatic. With an indicate system, the operator knows how to achieve the grade specified in the design requirements for his particular area by tracking information that appears on a display inside the cab. Indicate systems provide the operator with visual guidance so he can place the cutting edge or bucket properly, but he maintains control of the equipment. With an automatic system, the operator drives the machine, but the various systems—laser, GPS, etc.—control the movement of the blade or the bucket to achieve the same result. The operator doesn’t have to do anything but keep the machine moving in the right direction. The automatic system places the cutting edge appropriately on the design surface, and the machine does the rest.
An indicate system still requires the operator to know where to fill, where to cut, and where to deposit dirt, but the automatic system allows him to achieve his specified grade more precisely and efficiently.
Machine control has revolutionized the construction industry by making it possible for jobs to be completed more quickly and with the highest degree of accuracy. With wireless technology, a contractor can match a design engineer’s specifications to within one-tenth of a foot. Also, the technology lets him work in real time so design changes can be made or incorporated into the job site in practically an instant. With a wireless computer in the cab of his pickup truck, a contractor can receive up-to-the-minute progress reports from his equipment, download design changes sent by the engineer, and blend the two seamlessly by programming the new design specs into, say, the GPS-controlled hydraulic system.
Machine control systems operate through microprocessors situated deep within the equipment, which monitor every aspect of a machine, including operating information such as engine temperature, fuel, and oil use. They also control the critical hydraulic system that allows a blade or bucket to move with ease and accuracy.
Whatever the job site, every project begins with plumb, level, and square reference points from which the rest of the construction grows. A laser is the tool of choice for bright, crisp two-dimensional reference points or for an accurate plumb layout. Contractors can choose from carpenter levels, laser levels, rotary levels, and hybrid laser products.
For the person who installs acoustic ceilings or cement flatwork, for example, a rotating laser with a detector is necessary. Rotating lasers provide a continuous plane, either vertical or horizontal.
Some lasers are ideally suited for large job sites and agricultural land leveling and feature an integrated radio remote controller capable of two-way communication up to 1,000 feet. Radio communications between the remote and the base laser allow the operator to verify adjustments right from the cab of a machine.
Still others provide complete visual grade control with up to nine channels of information and three on-grade positions. The operator can tell at a glance how much grade he needs to cut, which makes grade control a one-person job. The grade checker can turn his attention elsewhere.
A laser also can provide three-dimensional positioning information by way of a machine control system. A fan-beam laser communicates digital control data to a receiver attached to the machine. The receiver takes in elevation, design cross-slope, and steering information, which it sends on to the control box.
Another system looks to the sky for information about location, position, and direction. GPS is a worldwide radio-navigation system formed from a constellation of 24 satellites and their ground stations. This particular constellation was launched and is operated by the United States. Other constellations are orbiting some 11,000 miles up in space, including GLONASS, operated by Russia, and Galileo, launched by the European Space Agency.
Global positioning allows construction engineers to take information broadcast by the satellites and use it to calculate the required position of equipment and survey lines to achieve accuracy to within one-tenth of a foot. Some operate in collaboration with laser systems for even greater precision. On the job site, GPS receivers are attached to machines, which pass data to an onboard computer that holds digitized site information. In real time, the information is broadcast from the satellite constellation to the receiver and on to the computer to guide the equipment’s movements. In an indicate system, the data appear on a monitor inside the cab, and the operator uses the data to guide the machine. With an automatic system, the computer directs the movements of the machine, such as controlling its hydraulics and raising or lowering a blade or bucket automatically.
Often a contractor will use an indicate system for the bulk of an earthmoving job and an automatic system for the fine grading.
With advances in machine control and the subsequent development of machine interface systems that keep a bulldozer and other construction equipment on the job, construction workers find themselves scaling a learning curve to become proficient in the new technologies. Clutch-and-brake and cable-control have given way to hydraulic systems that detect the slightest motion of a joystick and respond accordingly. It’s a new world for contractors and operators, and those who resist the new technology will likely find themselves left in the dust.
Equipment Systems
Exploring the various equipment systems that make backhoes, excavators, skip/loaders, and other construction beasts move with agility and relative ease, Grading & Excavation Contractor’s new Technology in Construction section will take a look at the new technology that is changing the way construction equipment works and operators do their jobs. The key components are hydraulics, mechanical systems, electrical systems, controls and instrumentation, power plants, transmissions, and components and accessories. In this first issue we offer an overview of each component and how together they make for a powerful piece of equipment. In subsequent issues we’ll examine each component separately and in greater detail.
Much has changed in the world of equipment systems, not the least of which is hydraulics. Hydraulic pressure gives construction equipment much of its power by making it possible for the individual components of a piece of construction equipment to move. A hydraulic system consists of hydraulic lines, a reservoir of hydraulic fluid, a pump, and a series of pistons. In the new hydraulic technology, electric current rather than a pushrod causes valves to open and close.
Mechanical systems also have undergone changes in recent years. Steering wheels, pedals, and levers are being eliminated in favor of joysticks that allow the operator to keep his hands on more than one control. With one stick he can move the backhoe forward or backward, and with the other he can control the dig of the bucket.
Similarly, advances in hydrostatic transmissions allow the operator to choose the appropriate travel speed for the job and enable him to shift back and forth from forward to reverse without using the clutch or brake. In the past, an operator had to pay attention to a host of factors while getting his grading or excavation job done. Now an on-board computer handles much of that. When the computer detects an unbalanced load on the blade, for instance, it makes the appropriate adjustment automatically.
With electrical systems, the significant change is the controller area network (CAN) serial bus, which serves as a communication system for the machine. With the new technology, electrical systems are more interrelated with the operation of the machine as a whole. With the CAN bus, for example, variations in current cause valves to open and close rather than the operator flipping a lever and doing it manually. A special feature of the CAN bus is that components can be plugged in modularly and don’t impact any existing wiring.
As technology has moved forward, so have instrumentation and control. The on-board computer allows for a continuous stream of information, all of which appears on a digital monitor system. The operator has quick access to the machine’s performance history and diagnostics, and for those machines equipped with after-market global positioning systems, the monitor system allows him to switch back and forth between machine function data and global positioning system (GPS) information.
While GPS is a popular addition to a machine’s standard features, a plethora of aftermarket components, accessories, and systems has been developed that allow machine operators to use their equipment in different ways. An excavator, for example, can become a rock cutter when the bucket is replaced by a hydraulic rock hammer.
The past two years have seen some tremendous changes in construction equipment and operation. In the old days, a backhoe ran pretty simply. A carburetor, generator, and battery and a fairly simple system of hydraulic valves kept it going. The operator controlled it with levers and did everything by eye because all the components functioned manually. Speed and accuracy depended on his skill. Not so today when equipment manufacturers follow a never-ending quest to improve the performance of their machines and outfit them with user-friendly controls that make grading and excavation work more science than art.
Software for Contractors
With the right software applications and systems, a contractor can keep track of every aspect of his business from managing his payroll to tracking maintenance and repair on his bulldozer.
Within their categories, the various software programs differ from one another in a few respects such as window design and individual features. A general overview of current software follows, and in subsequent issues Technology in Construction will take a closer look at individual applications and explore how professionals have applied them to their businesses.
Construction and project management software such as Smart Contractor allow a user to control practically all the administrative tasks associated with his business. Fully integrated with Quickbooks, the software can create job estimates; generate custom job proposals and contracts; create job activity schedules complete with employees and subcontractors; generate requests to vendors and subcontractors; create purchase orders; track change orders and allowance variances; print invoices or bank draw requests; track payment receipts and other accounts receivable; track job costs; print job recap reports and make final payment calculations; create a variety of cash flow reports; track customer contacts; and even store job-site photos.
With its Quickbooks integration, this type of software also allows a contractor to manage financial and accounting issues such as accounts payable and everything related to payroll.
Fleet management software enables a business owner to maintain complete records on all his equipment. The software generates reports that cover a range of topics including vehicle costs; a parts inventory; fueling; tire management; mechanical productivity; purchasing information; vendor information; driver interface and reporting; depreciation; and asset tracking.
Equipment and inventory management software such as that offered by Cheetah allows contractors to know at all times where their equipment is located and how it is being used. It also enables contractors to maintain service records, create repair and maintenance work orders, and even track warranties.
In addition to software applications specializing in construction business management, a variety of specialty software systems cover areas such as human resource management; education and training; civil engineering and surveying systems; computer-aided design (CAD); and geographical information systems and mapping.
Human resources software automates the process of employee management so contractors can tailor employee record-keeping to fit their needs. With the software they can track employment history, status changes such as pay rates or tax changes, 401(k) administration and eligibility, health benefit eligibility, and more.
Other innovative software applications assist with fieldwork by calculating cuts and fills, stripping, strata quantities, subgrade materials, topsoil re-spread, areas, lengths, trench excavation, and backfill from digitizer input or CAD import. These applications can automatically list the fill required under each subgrade as well as any subgrade material; calculate the water, storm, and sanitary sewer excavation by strata; and backfill quantities from traced profiles or from contours. They can assist with highway construction, site development, and general earthmoving projects. Special features of these include a built-on AutoCAD engine; digitizing, drillhole, trenching, and roads routines; calculating volumes and material quantities; cutting and filling color maps and labels; creating three-dimensional drive-over simulation; preparing files for stackout and machine control; and two-dimensional to three-dimensional conversion routines for linework and spot elevations.
September-October 2006
Technology in Construction
Lasers
Once the stuff of science fiction and
Star Wars movies, lasers have moved into the mainstream and taken their place in consumer electronics, in doctors’ offices, and even on construction sites. The same laser beam that causes a CD player to produce music and allows an eye surgeon to restore a patient’s 20-20 vision in a matter of moments can help a bulldozer operator make fast and accurate work of a grading or excavating assignment.
“If you’re trying to achieve a perfectly flat grade, a laser is absolutely best for that,” says Boyd Reynolds, product marketing manager for Leica Geosystems. “And if you’re trying to achieve a grade that’s sloped, a laser is perfect. It provides wonderful accuracy.”
Indeed, most lasers boast an accuracy to one-thirty-second of an inch.
“Professional construction lasers deliver very tight accuracy,” says Pat Bohle, division vice president of marketing for Trimble’s construction division. “That’s especially important for applications such as concrete pad work for large commercial buildings, which typically have very tight tolerances.” While general and concrete contractors commonly rely on construction lasers and receivers for elevation control, he continues, they’re also ideal for use on smaller machines such as backhoes, skid-steers, and mini excavators for site preparation applications.
“The use of lasers for these applications is less adopted,” he notes. “However, they do provide significant productivity improvements and tight accuracy control for a range of dirt-moving applications.”
But what is a laser and how does it work? The word laser is an acronym for “light amplification by stimulated emission of radiation.” A laser is a specific kind of light, the qualities of which make it ideal for construction purposes. Laser light, for example, is monochromatic. It contains one specific color that is easy to recognize. In addition, laser light is highly directional. Light from most sources spreads out as it travels, so as the distance from the source increases the amount of light hitting any given area actually decreases. Laser light, however, has a very tight beam that remains strong and concentrated over a distance as much as 2,500 feet long. Think about a flashlight, which releases light in many directions. The beam becomes weak and diffused. Laser light travels as a parallel beam and spreads very little.
For grading applications, the rotating construction laser is the tool of choice. Think of it as a high-tech level that emits one or more light beams through its apertures to create a level reference plane. The laser box, from which the beam originates, sits on a tripod, and as the beacon rotates, it expands the level plane to cover a 360-degree-diameter range.
Rotating lasers come in three basic types: flat plane, single slope (also called single grade), and dual slope (also called dual grade). Most are self-leveling, which means you take it out of the box and set it on a tripod and it automatically finds and maintains level within a specified range. Manual level lasers, which require the operator to adjust the unit by hand using thumb screws and bubble vials, also exist, but over the last five years most have given way to electronic models that require only rough leveling upon setup.
A flat-plane laser emits a single horizontal beam from its rotating beacon. The beam varies in distance, generally ranging from 500 to 1,500 feet. It is commonly used for checking elevation and setting foundations and concrete.
A single-slope laser allows the operator to dial in one axis of a slope. It might be used for any general construction application, including excavation and sloped pads. A farmer might use a single-slope laser, for example, to grade a hog pen in which he wants everything to fall to one corner. The distance range for single-slope laser beams is similar to that of flat-plane lasers.
With dual-slope lasers, the beacon emits simultaneous horizontal and vertical beams to establish both level and plumb reference lines. The surface can be flat or tilted with a grade. A dual-slope laser has a distance range of 1,000 to 2,500 feet.
So how, exactly, does a laser—whether flat plane, single slope, or dual slope—function on the construction site? A construction laser consists of the laser beacon itself, which produces the beam of light, and a receiver that registers the beam and lets the bulldozer operator know whether or not he’s on target. The laser beacon sits atop a tripod strategically located on the construction site. The receiver is attached to the appropriate part of the equipment—say, the blade of the bulldozer. It is situated on a measuring rod, which allows the operator to place the blade properly in relation to the site’s benchmark. The benchmark determined by the surveyor and project designer indicates the height, width, and length of the area being graded.
“All construction sites have a benchmark,” says Rob Roske, owner of Montana Lasers LLC, “and usually there are two of them.”
The laser is set at some number of feet above the benchmark, and as the beam hits the receiver, which is adjusted on the measuring rod to the same number of feet above the benchmark, the receiver lets out a beep indicating whether the blade is too high, too low, or just right. There is no need for reading grade stakes or having a work partner tell the operator where or how much to adjust the blade.
In the pre-laser era, such work would have been accomplished with automatic or manual levels with two people on the job—one to operate the equipment and another to point out where the grade was—say, a tenth of an inch too high or maybe two-tenths of an inch too low.
“Now the receiver will let you know if you need to move the blade up or down,” says Roske.
Adds Bohle, “By providing tight elevation control for a range of tasks, a contractor can work more productively.”
As the laser rotates, it creates a plane of light and will register on a receiver operating anywhere within the circle. Every laser is rated by the manufacturer for a certain distance range, and the keys to accuracy are staying within that range and making sure nothing interferes with the flow of the beam.
Although a laser rated at, say, 1,500 feet can be detected by a receiver as far as 2,500 feet away, it won’t provide an accurate reading at such a distance. As the beam extends beyond its established rating, two things happen. First, the light begins to diffuse slightly and in doing so becomes less precise, and second, the curvature of the earth actually impedes the beam as it heads toward the receiver.
Construction experts agree that in determining which type of construction laser—flat plane, single slope, or dual slope—will meet his needs, a contractor should consider what he wants to accomplish with it.
“You need to know the applications, what you want to do with it,” says Reynolds. “Some lasers are more accurate than others; some reach farther than others. If you’re doing a lot of sports fields, for example, you’ll want a single-grade laser. More complex jobs require dual grade.”
If the potential for machine control is a consideration, look for a unit with a laser beacon that rotates at least 600 revolutions per minute. Some go as high as 900 revolutions per minute, but 600 is the minimum for machine control. In some models, the laser rotates only 300 revolutions per minute and while that may be fine when the operator controls the blade or bucket, when a contractor decides to step up to the next level and let machine control run the show, his 300-revolutions-per-minute laser will be too slow.
“The laser market has become fairly homogenous, and there’s not a lot of difference between competitors,” continues Reynolds. “It’s important, though, to key in on a dealer that will provide service. The laser will get knocked over, so you need to find a reputable dealer with good service.”
Construction lasers range in price from $500 to $800 for a flat-plane model, $1,000 to $1,600 for the single slope, and $6,000 to $7,200 for the dual slope. A contractor prepared to spend $800 on a flat-plane laser might do well to consider springing an extra few hundred dollars for the single-slope variety. According to grading professionals, the more complicated jobs he’ll be able to take on will more than make up the difference.
Coming up: Construction lasers and machine display and control—letting the equipment do all the work.
Pumps: An Introduction
Simply defined, a pump is a machine or device used to raise, compress, or transfer fluids from one place to another. Pumps come in different shapes, sizes, and designs and thus serve a variety of purposes on a construction site.
When a backhoe rolls forward on its tracks and scoops up a bucket of dirt, for example, a complex set of hydraulic systems makes each movement possible. At the center of the action are hydraulic pumps, which, in this case, provide the flow of pressurized oil the various systems need in order to function.
Here are five types of pumps commonly used on construction sites and heavy equipment:
Gear Pumps. Gear pumps generally are used to pump thick fluids such as oil. They consist of a pair of meshing gears that rotate in a housing. As the fluid moves into the inlet region, it is trapped between the gear teeth and carried around to the outlet side. The pressure in the outlet region builds up until it is high enough to discharge the fluid.
Piston Pumps. The basic piston pump consists of some number of pistons housed within individual cylinder barrels. As the pistons are pulled upward within the cylinder barrel, a vacuum is created that sucks fluid through an intake valve into the open space. When the pistons are pushed downward, the fluid is expelled through exit valves. The pumping rate can be adjusted by altering the distance the pistons retract within the cylinders. Doing so controls the amount of liquid discharged by each stroke. Piston pumps are commonly used on excavators and other heavy construction equipment.
Vane Pumps. Rotary vane pumps use rotating assemblies to move fluid within the pumping chamber. The vanes are mounted to a circular rotor that sits within a circular cavity. The centers of the circles are offset, and when the rotor spins, vanes are pushed outward. As the vane rotates along the intake side of the pump, the volume area increases and fluid is drawn into the vane chambers. Along the discharge side, the volume area decreases and fluid is forced out of the pump. Vane pumps have common applications on scrapers, conveyer belts, power steering, and automatic transmission.
Centrifugal Pumps. Centrifugal pumps move fluid by means of centrifugal force. Several ribs or vanes are mounted on a revolving disk within the assembly, and as the disks turn, they create suction, which pulls fluid into the pump. The fluid occupies the space between the vanes, and as it rotates with the blades, it is forced out through an exit valve. Centrifugal pumps often are used for pumping liquids for water supply systems, mines, irrigation, dredging, and sewage disposal.
Progressive Cavity Pumps. With a progressive cavity pump, fluid moves within a cavity that progresses along the pump. A rotor fits into the pump body, and as it turns, the cavity moves and fluid is sucked in to fill it. With continued rotation, the fluid travels through the cavity and out through the discharge. Cavity pumps are often used for sewage and cement applications.
Bidding and Estimating Software
In the old days of bidding and estimating, a contractor might have pulled out a pad of paper, a ruler, and a planometer to calculate the cost of a proposed job. He’d sharpen his pencil and write out the details by hand. He’d compute, either manually or with a calculator, the number of people he’d need to get the job done, how many hours they’d put into it, how much materials would cost, and what equipment would be required. An experienced contractor carried a lot of the information in his head—he’d done enough work over the years to make pretty accurate estimates.
Except when he didn’t.
A miscalculation—inadvertently counting as square feet what should have been square yards, actual costs of materials exceeding estimates—or any of a host of other errors could cost him big time, especially if he didn’t become aware of it until he was well into the project. Now, many computer-literate contractors use Microsoft Excel to complete estimates and plan out projects on spreadsheets. The possibility for error, however, is still high. Plug an incorrect formula or figure into one cell and the entire bid can be off.
Enter software designed especially for bidding, estimating, and project management. With products from companies such as Bid2Win, Constructw@re, and Corecon, contractors can stay on track from initial estimates to project completion. The software also allows them to streamline design and project management among team members throughout the life of the project.
“Bidding and estimating software allows a contractor to put together quantities and prices for a particular bid,” says Michael Gillum, director of research and development for Quest Solutions. His company produces six different software packages. “It could be for a pool, a house, a building, or a septic tank. The software allows it to be done much faster and more accurately because the computer is doing the math for you.”
Any contractor doing more than $1 million of work annually can benefit from some variety of the software.
“If someone digs out septic tanks and that’s all they do, they don’t need it,” continues Gillum. “If they do $1 million a year, though, and they want to stay competitive, they do.”
Software for bidding, estimating, and project management ranges in price from $1,000 to $20,000. Typically, the low-end programs will do measurements but won’t assist with pricing or anything else. At the high end are programs equipped with a host of bells and whistles that accommodate multi-users.
“A majority of businesses out there are under 30 employees,” says Norm Wendl, founder of Huntington Beach–based Corecon Technologies Inc. “Those people using Excel or Word for estimating and project management aren’t systematizing their work and aren’t able to truly track if they’re making money on certain activities for a job.”
Bidding, estimating, and project management software address the specific needs of professionals in the construction industry. It gives them a degree of standardization, so they don’t have to rely on a mix of spreadsheets and word processing documents to track their information. In addition, specific information is often built in so the contractor doesn’t have to research it himself. It might include, for example, the cost of concrete or lumber in the user’s area or the going price for labor or equipment use. The information on the database is updated on a weekly, monthly, or annual basis and based on figures specific to the user’s geographic area. Database companies such as RS Means and Construction Estimating Institute make the updates available via fax or an electronic spreadsheet the contractor can import into his existing database.
“The software will come with an average number for his area,” notes Gillum. “[The contractor] will add in his profit, travel time, the things that no software can predict.”
“A lot of businesses use Excel for estimating and QuickBooks for managing,” continues Wendl. “They may have a good business and may be making money at the end of the month, but the problem is they don’t know where they’re making money. On some bid items they’re making a lot, and on others they’re losing. With QuickBooks they can do accounts payable, timecards, payroll, et cetera, but it doesn’t give an accurate picture of which bid items are making an actual profit.”
Some applications, such as Bid2Win and Bid2Win Enterprise, Constructw@re, and Quest, a product of Quest Solutions, are independent software programs that are loaded onto a user’s computer. Corecon Technologies’ Corecon 2006 is a Web-based operation, which means users pay a monthly subscription fee and can access the software from remote locations using a secure login ID and password. Depending on the size of the business and the number of users, it can be more cost-effective than a self-contained software program a business owner would purchase outright.
“Corecon 3, our last Windows-based product, was $2,000 per user with a $400 annual maintenance fee,” says Wendl. “Corecon 4 and the second-generation Corecon 2006 ranges from $40 to $60 per user per month for a one-year contract.”
Some contractors would prefer to own their software program and customize it for their use. They’d rather not pay a monthly fee or deal with passwords and user names.
“Most contractors aren’t computer savvy,” says Gillum. “Often, this is the first time they’re using computers. A contractor who’s been in the business for 10, 20, or 30 years hasn’t been working on a computer. He wants to turn it on, walk through a few steps, and turn out a bid. It has to be easy and intuitive.”
On the bidding and estimating side, the software allows for detailed line-item estimates using industry-standard databases such as RS Means. It can track labor and equipment items, crews, materials, work assemblies, and formulas. To manage subcontractors, the software makes it possible to send out multiple bid requests, either electronically or via fax, and have subs and suppliers respond with their prices via the Internet. It can transform estimates into detailed prime contracts and estimate line items into subcontracts and purchase orders. Document control allows a general contractor to track, send, create, and customize requests for information, submittal packages, daily logs, and more.
For project management, the software assists the contractor in practically every aspect of running a job. First, it can automatically transfer the successful bid information to a project management file so the contractor doesn’t have to input for a second time all the data associated with the project. For day-to-day management, the software handles, among other tasks, document control, quality control, scheduling, job cost control, contract administration, project analysis, budgets, and even e-mailing and faxing reports. It will keep daily logs; track permits, specifications, and miscellaneous tests and inspections; maintain a project calendar; track equipment; maintain labor timecards; and manage all the details associated with subcontractors.
Applications such as Corecon 2006 have interface links to Microsoft Office, Microsoft Small Business Accounting, and QuickBooks so it can transfer project financial information, including project bills, invoices, timecards, and accounts payable and receivable, from one program to another.
Although software for estimating and bidding and project management has existed for 20 years, research shows that a full 50% of industry professionals still have not incorporated it into their business operations. For those who made the leap, however, business on average has enhanced ten-fold.
“Ten times more productivity is huge,” declares Gillum. “A guy who runs a bulldozer all day, goes home to his family, and then has to do estimates until 2 a.m. isn’t happy. But with the software doing so much of the work for him he can put out more bids, increase his productivity, grow his business, and spend more time with his family.”
IntroductionSome call it the biggest change in land development since the Industrial Revolution. They’re talking about the technology boom that is transforming the way design engineers, contractors, and job-site crews tackle their grading and excavation jobs. What used to be done manually can now be completed more efficiently and accurately with, say, a laser or global positioning system (GPS). Machine control systems like these and others bring a precision to the work site that contractors and equipment operators couldn’t fathom 10 years ago. No more waiting for a layout or grade staking to indicate how much dirt needs to be moved in a work area, and no more rolling repeatedly over a test strip to determine how many passes are necessary to attain the requisite compaction. Gone are the days of measurements taken by hand and operators relying on their judgment and experience to grade an area.
Likewise, equipment systems have taken a giant leap forward in recent years with electronically controlled fuel injection systems taking the place of carburetors, for example, and hydraulic valves operating by way of changes in electric current rather than a pushrod. And that’s just the beginning. The dozers of the future will resemble their predecessors about as much as a Ferrari does a Model A Ford.
Grading & Excavation Contractor is joining this 21st century construction revolution with a new regular section called Technology in Construction that will introduce, highlight, and examine the new technologies and systems. In these pages you’ll read about everything from equipment controls and systems that alter the way a backhoe or skip/load operator moves his machine to a host of software programs that help a contractor organize and manage all aspects of his business.
You’ll meet professionals in the field who share their experiences with the new technologies, explaining how they’ve incorporated them into their projects and how they’ve increased their productivity and improved their bottom lines. In the process, you’ll get ideas about how the new technology can help you improve and even expand your own business.
“We’re living history,” Topcon’s Richard Rybka says of the technology evolution. “You see people using it across the country from the Pacific Northwest to New England. It’s a massive progressive change.”
From lasers to construction management software, technology is creating a whole new world within the construction industry. New job opportunities are emerging for people ready catch this wave of the future. GPS specialists, for example, are finding themselves in high demand, as is the crew member who is well versed in data management, field operations, and how machinery works.
“It’s not only changing the way contractors do business but their responsibilities on the job site,” Rybka says of the technology that provides accurate, up-to-the-minute information that gives contractors a professional edge. “It’s really changing the contractor’s position on the ladder.”
There’s no doubt technology will continue to march forward and the construction professionals who take advantage of it will lead the industry. By featuring state-of-the-art machine controls, software programs, equipment systems, and more, Technology in Construction will help you stay at the head of the pack.
Machine Control
In the last few years a major change has swept over the world of construction equipment, and it can be summed up in two words: machine control. Machine control can take practically all of the guesswork out of grading and excavation by using laser, global positioning, and other advanced technology to set parameters and measurements otherwise done manually or with a trained eye.
Truly the wave of the future, machine control means as much to construction work now as the tractor did to farming almost 100 years ago.
Machine control consists mainly of laser and global positioning systems (GPS), machine interface systems, controls, and displays. To help acquaint readers with the technology that nearly all will encounter over the course of their professional lives, Technology in Construction will introduce the components, highlight their uses, and show how they come together in one piece of equipment. Descriptions and explanations will help readers build a basic understanding of how the elements work and how readers can incorporate them in their own construction jobs.
The goal of a grading and excavation job is to work a construction site with the appropriate equipment to achieve a design created by an engineer. Even if the job is a flat building pad, it usually has some slope. That slope can be created more efficiently and accurately than ever with the new technology. It might be a laser control system that provides two-dimensional control; it could be a robotic total station used for measuring angles and distances. Each of these, along with global positioning systems, calculate precise measurements and relay them to a display inside the cab.
Machine control systems fall into two categories: indicate and automatic. With an indicate system, the operator knows how to achieve the grade specified in the design requirements for his particular area by tracking information that appears on a display inside the cab. Indicate systems provide the operator with visual guidance so he can place the cutting edge or bucket properly, but he maintains control of the equipment. With an automatic system, the operator drives the machine, but the various systems—laser, GPS, etc.—control the movement of the blade or the bucket to achieve the same result. The operator doesn’t have to do anything but keep the machine moving in the right direction. The automatic system places the cutting edge appropriately on the design surface, and the machine does the rest.
An indicate system still requires the operator to know where to fill, where to cut, and where to deposit dirt, but the automatic system allows him to achieve his specified grade more precisely and efficiently.
Machine control has revolutionized the construction industry by making it possible for jobs to be completed more quickly and with the highest degree of accuracy. With wireless technology, a contractor can match a design engineer’s specifications to within one-tenth of a foot. Also, the technology lets him work in real time so design changes can be made or incorporated into the job site in practically an instant. With a wireless computer in the cab of his pickup truck, a contractor can receive up-to-the-minute progress reports from his equipment, download design changes sent by the engineer, and blend the two seamlessly by programming the new design specs into, say, the GPS-controlled hydraulic system.
Machine control systems operate through microprocessors situated deep within the equipment, which monitor every aspect of a machine, including operating information such as engine temperature, fuel, and oil use. They also control the critical hydraulic system that allows a blade or bucket to move with ease and accuracy.
Whatever the job site, every project begins with plumb, level, and square reference points from which the rest of the construction grows. A laser is the tool of choice for bright, crisp two-dimensional reference points or for an accurate plumb layout. Contractors can choose from carpenter levels, laser levels, rotary levels, and hybrid laser products.
For the person who installs acoustic ceilings or cement flatwork, for example, a rotating laser with a detector is necessary. Rotating lasers provide a continuous plane, either vertical or horizontal.
Some lasers are ideally suited for large job sites and agricultural land leveling and feature an integrated radio remote controller capable of two-way communication up to 1,000 feet. Radio communications between the remote and the base laser allow the operator to verify adjustments right from the cab of a machine.
Still others provide complete visual grade control with up to nine channels of information and three on-grade positions. The operator can tell at a glance how much grade he needs to cut, which makes grade control a one-person job. The grade checker can turn his attention elsewhere.
A laser also can provide three-dimensional positioning information by way of a machine control system. A fan-beam laser communicates digital control data to a receiver attached to the machine. The receiver takes in elevation, design cross-slope, and steering information, which it sends on to the control box.
Another system looks to the sky for information about location, position, and direction. GPS is a worldwide radio-navigation system formed from a constellation of 24 satellites and their ground stations. This particular constellation was launched and is operated by the United States. Other constellations are orbiting some 11,000 miles up in space, including GLONASS, operated by Russia, and Galileo, launched by the European Space Agency.
Global positioning allows construction engineers to take information broadcast by the satellites and use it to calculate the required position of equipment and survey lines to achieve accuracy to within one-tenth of a foot. Some operate in collaboration with laser systems for even greater precision. On the job site, GPS receivers are attached to machines, which pass data to an onboard computer that holds digitized site information. In real time, the information is broadcast from the satellite constellation to the receiver and on to the computer to guide the equipment’s movements. In an indicate system, the data appear on a monitor inside the cab, and the operator uses the data to guide the machine. With an automatic system, the computer directs the movements of the machine, such as controlling its hydraulics and raising or lowering a blade or bucket automatically.
Often a contractor will use an indicate system for the bulk of an earthmoving job and an automatic system for the fine grading.
With advances in machine control and the subsequent development of machine interface systems that keep a bulldozer and other construction equipment on the job, construction workers find themselves scaling a learning curve to become proficient in the new technologies. Clutch-and-brake and cable-control have given way to hydraulic systems that detect the slightest motion of a joystick and respond accordingly. It’s a new world for contractors and operators, and those who resist the new technology will likely find themselves left in the dust.
Equipment Systems
Exploring the various equipment systems that make backhoes, excavators, skip/loaders, and other construction beasts move with agility and relative ease, Grading & Excavation Contractor’s new Technology in Construction section will take a look at the new technology that is changing the way construction equipment works and operators do their jobs. The key components are hydraulics, mechanical systems, electrical systems, controls and instrumentation, power plants, transmissions, and components and accessories. In this first issue we offer an overview of each component and how together they make for a powerful piece of equipment. In subsequent issues we’ll examine each component separately and in greater detail.
Much has changed in the world of equipment systems, not the least of which is hydraulics. Hydraulic pressure gives construction equipment much of its power by making it possible for the individual components of a piece of construction equipment to move. A hydraulic system consists of hydraulic lines, a reservoir of hydraulic fluid, a pump, and a series of pistons. In the new hydraulic technology, electric current rather than a pushrod causes valves to open and close.
Mechanical systems also have undergone changes in recent years. Steering wheels, pedals, and levers are being eliminated in favor of joysticks that allow the operator to keep his hands on more than one control. With one stick he can move the backhoe forward or backward, and with the other he can control the dig of the bucket.
Similarly, advances in hydrostatic transmissions allow the operator to choose the appropriate travel speed for the job and enable him to shift back and forth from forward to reverse without using the clutch or brake. In the past, an operator had to pay attention to a host of factors while getting his grading or excavation job done. Now an on-board computer handles much of that. When the computer detects an unbalanced load on the blade, for instance, it makes the appropriate adjustment automatically.
With electrical systems, the significant change is the controller area network (CAN) serial bus, which serves as a communication system for the machine. With the new technology, electrical systems are more interrelated with the operation of the machine as a whole. With the CAN bus, for example, variations in current cause valves to open and close rather than the operator flipping a lever and doing it manually. A special feature of the CAN bus is that components can be plugged in modularly and don’t impact any existing wiring.
As technology has moved forward, so have instrumentation and control. The on-board computer allows for a continuous stream of information, all of which appears on a digital monitor system. The operator has quick access to the machine’s performance history and diagnostics, and for those machines equipped with after-market global positioning systems, the monitor system allows him to switch back and forth between machine function data and global positioning system (GPS) information.
While GPS is a popular addition to a machine’s standard features, a plethora of aftermarket components, accessories, and systems has been developed that allow machine operators to use their equipment in different ways. An excavator, for example, can become a rock cutter when the bucket is replaced by a hydraulic rock hammer.
The past two years have seen some tremendous changes in construction equipment and operation. In the old days, a backhoe ran pretty simply. A carburetor, generator, and battery and a fairly simple system of hydraulic valves kept it going. The operator controlled it with levers and did everything by eye because all the components functioned manually. Speed and accuracy depended on his skill. Not so today when equipment manufacturers follow a never-ending quest to improve the performance of their machines and outfit them with user-friendly controls that make grading and excavation work more science than art.
Software for Contractors
With the right software applications and systems, a contractor can keep track of every aspect of his business from managing his payroll to tracking maintenance and repair on his bulldozer.
Within their categories, the various software programs differ from one another in a few respects such as window design and individual features. A general overview of current software follows, and in subsequent issues Technology in Construction will take a closer look at individual applications and explore how professionals have applied them to their businesses.
Construction and project management software such as Smart Contractor allow a user to control practically all the administrative tasks associated with his business. Fully integrated with Quickbooks, the software can create job estimates; generate custom job proposals and contracts; create job activity schedules complete with employees and subcontractors; generate requests to vendors and subcontractors; create purchase orders; track change orders and allowance variances; print invoices or bank draw requests; track payment receipts and other accounts receivable; track job costs; print job recap reports and make final payment calculations; create a variety of cash flow reports; track customer contacts; and even store job-site photos.
With its Quickbooks integration, this type of software also allows a contractor to manage financial and accounting issues such as accounts payable and everything related to payroll.
Fleet management software enables a business owner to maintain complete records on all his equipment. The software generates reports that cover a range of topics including vehicle costs; a parts inventory; fueling; tire management; mechanical productivity; purchasing information; vendor information; driver interface and reporting; depreciation; and asset tracking.
Equipment and inventory management software such as that offered by Cheetah allows contractors to know at all times where their equipment is located and how it is being used. It also enables contractors to maintain service records, create repair and maintenance work orders, and even track warranties.
In addition to software applications specializing in construction business management, a variety of specialty software systems cover areas such as human resource management; education and training; civil engineering and surveying systems; computer-aided design (CAD); and geographical information systems and mapping.
Human resources software automates the process of employee management so contractors can tailor employee record-keeping to fit their needs. With the software they can track employment history, status changes such as pay rates or tax changes, 401(k) administration and eligibility, health benefit eligibility, and more.
Other innovative software applications assist with fieldwork by calculating cuts and fills, stripping, strata quantities, subgrade materials, topsoil re-spread, areas, lengths, trench excavation, and backfill from digitizer input or CAD import. These applications can automatically list the fill required under each subgrade as well as any subgrade material; calculate the water, storm, and sanitary sewer excavation by strata; and backfill quantities from traced profiles or from contours. They can assist with highway construction, site development, and general earthmoving projects. Special features of these include a built-on AutoCAD engine; digitizing, drillhole, trenching, and roads routines; calculating volumes and material quantities; cutting and filling color maps and labels; creating three-dimensional drive-over simulation; preparing files for stackout and machine control; and two-dimensional to three-dimensional conversion routines for linework and spot elevations.