Stake out

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Everyone knows that surveying is a crucial process on any and all construction sites. Everyone knows that for a project to be completed in the most efficient way, surveyors need to be the first on site and the last ones to leave.

Less obvious, is the equipment available to survey professionals, which, according to industry experts, could save a substantial amount of time and money.

Importantly, it seems that far from the days of strings and tape measures, today’s surveyors have the option to rely on advanced GPS rovers, robotic total stations, infrared beams and machine control systems.

As well as increasing efficiency and improving the quality of construction, apparently these systems also help to drive production and boost worker safety.

This being the case, one has to wonder why the Middle East is continuing to fall behind its global competitors when it comes to technology take-up.

“We are slightly behind, but we’re catching up quickly,” says global survey technology supplier Topcon’s representative Mick Hales.

“Previously and currently, local contractors have had in their minds that these are labour-saving tools and this is not the area they focus on for improving the bottom line. Actually, these are material- and time-saving tools as well.”

Trimble, another major manufacturer with a Middle East presence, has provided survey technology to several high profile projects in the region, including the Dubai Pearl, the Yas Marina F1 race track and the Paris-Sorbonne University in Abu Dhabi.

Agreeing with Hales, regional manager for the construction sector Andrew Caldwell, suggests that the problem is not so much about companies ignoring technology, but about their failing to adopt the latest versions.

“Survey technology is like any other technology. It changes over the years just like mobile phones and computers, where every year you have a new product that’s more efficient, faster and has a bigger memory. In the Middle East, it is about getting firms to move up that level of technological advancement.”

The good news, he says, is that following the economic crisis, things are starting to change. “Companies have realised that to be competitive they have to move with technology. We’ve been working with a lot of large companies on projects for some time, but recently, we’ve started to get through to the subcontractors.”

So how does the latest surveying technology help firms improve the efficiency of their projects?

“Survey equipment consists of a combination of technologies merged into what we typically see on construction sites today,” says Hales, referencing what is probably the biggest development in the construction survey world: GPS.

Unlike other systems, GPS technology relies on satellites, allowing firms to carry out a large amount of survey work at faster speeds.

Much more advanced than navigational GPS systems, those used in construction involve a surveyor clutching a handheld receiver or ‘rover’, receiving signals from both the satellites themselves and from a base station (an additional receiver positioned over what’s known as a control point).

These signals allow the surveyor to effectively stake out the project for the contractors according to the original design, which itself can be viewed on the surveyor’s handheld controller.

“GPS tends to be used for staking out road designs, long-range survey work and to pick out the original ground levels (OGLs),” explains Caldwell.

“The main advantage of GPS is that you can do work five times quicker and can cover much larger areas than you could using other technology.”

Hales agrees: “Real time GPS rovers can take point readings on the move giving XYZ coordinates at many times per minute. Some contractors use a four-wheeler to blanket the area with thousands of points in a few hours.”

The only downside, Caldwell says, is the level of accuracy – a GPS system only producing points within 8mm of the original design. Which brings us to total stations, or at least the latest technology behind them. Used for finer positioning and higher accuracy building, Total Stations are basically a theodolite with a distance metre.

“Total Stations are used for construction inside buildings, where a difference of 8mm is just not good enough,” says Caldwell. “If you’re building a lift-shaft for example, you can’t have an 8mm variance, as the lift will get stuck half way up.”

In terms of development, Total Stations are similar to GPS systems. Though they have been available in the market for the past decade, only recently has the technology advanced significantly.

Today, not only can companies save a significant amount of manpower by using robotic total stations in the place of mechanical, but more importantly, they can remove the chance of human error by introducing and integrating total stations with building information modeling (BIM) software.

“The latest survey technology inevitably involves a combination of hardware and software,” says Caldwell.

“Basically it allows you to extract the points from the original 3D, virtual design on the computer, input them onto a controller, take that controller to the field and connect it to a Total Station, which then shoots the points as laid out in the design and removes the opportunity for human error."

"In the past, someone would design the building, print out the paper plans and take them to the site, where they would go back 50 years and start pulling out tape measures.”

While the benefits related to improved efficiency are relatively obvious, those related to safety seem more obscure.

“If a survey crew is spending less time under the hot sun or deep in an excavation, then surely less injuries are going to occur,” says Hales, a strong advocate of the view that new opportunities for safety are one of the key advantages of today’s survey systems. Caldwell meanwhile, suggests safety can be improved through specific technology, namely that referred to as ‘direct reflex technoloy’.

“Previously, Total Stations worked by shooting a light beam to a prism on the building, which would reflect back and give you your point,” he explains.

“This new technology, which relies on infrared beams that reflect off most, and even black, surfaces to a certain extent, means you no longer need a prism to shoot to, and thus you don’t need to put someone on top of a building carrying a prism to get accurate measurements. It’s much quicker as well.”

With safety being such a massive Middle East priority at the moment, this may suggest that construction is driving the development of technology.

“No, technology has definitely led construction,” argues Caldwell.

“It’s not the industry demanding this new technology, but companies like us looking at ways to improve construction processes through technology, particularly when it comes to things like machine control systems, which are really changing the way construction is executed.”

Simply put, these latest survey systems are placed on top of machines used to move heavy earth, with a view to automating the machine’s hydraulics and controlling the blade, so all the operator has to do is drive.

Which leads to the inevitable question: is remotely controlled and robotic technology the future for construction?

“Probably,” says Caldwell.

“In some parts of the industry, like in the mines, almost all machinery is remotely controlled. But when this will happen, I really don’t know.”

Certainly, in the Middle East, there may be some way to go yet.

What about costs?
High costs are a concern for any contractor, especially as companies continue to battle with late payments and a shortage of cashflow.

Here’s what the experts have to say:

Trimble: “Survey technology is like any other technology, people use it because it helps them become more efficient and saves them money. So yes, there is capital investment for the equipment, but it is more than paid off during the lifecycle of one job. Depending on the size of a project, it can actually make contractors money.”

Topcon: “In some cases a project will only take advantage of the bare minimum required to finish the job, and any new technology might not be an advantage. However, all contractors should consult an expert during the tender process to see if any of this new technology could make a major impact. It sounds expensive when you first hear the price, but it usually has a payback value many times the original cost.”

Users of Topcon technology include:
• Arabtec
• Wade Adams
• Saif Bin Dariwish
• Al Kharafi