Construction World February 2023

Gauteng Piling handling challenging stabilising piling in Irene.

“However, because of the current economic crunch in the building industry, clients far too frequently regard geotechnical soil tests as a luxury – a factor that can either be watered down, or totally eliminated, to save costs. This attitude almost inevitably leads to increased costs later when it is discovered that suitable material is not present to secure the founding. Then the client faces a total re-design - and substantially increased cost,” he explains. “It has been shown over and over that if clients are not prepared to spend money upfront for geotechnical investigations to decide how a structure will be founded, further down the line they will face heavy compensation for not having done the preliminary investigation. The problem is that contractors, struggling to find and retain clients in the current slump, are reluctant to offend developers or property owners by insisting on initial soil investigations to determine the correct foundations. “For the piling operator, such reticence makes quotations a hit-and-miss affair. We are expected to guess how deep each of what could be 100 or more piles have to be. In the private sector, particularly, there is shocking ignorance about the need for soil investigations. A client once suggested that a rod could simply be hammered into the ground to avoid paying for proper geotechnical tests.” Maas believes that structural engineers should also carry the blame for not insisting on investigations to test soil conditions before foundations are provided. “Structural engineers vitally need soil investigations to arrive at cost saving designs for any structure, be it a new house or a major shopping centre. On a R200m project, sufficient geotechnical investigations could cost just R200 000. That’s surely a small price to pay if you consider what the cost - and other more serious - consequences could be if durable foundations are not provided,” he adds. 

27 CONSTRUCTION WORLD FEBRUARY 2023