Durban - Significant changes to the design of the collapsed Tongaat Mall, and starting construction before the plans were finished, created substantial problems for the structural engineer, an expert engineer testified on Monday.
Dr Piet Pretorius was the first witness called at the resumption on Monday of the inquiry into the Tongaat Mall tragedy.
Pretorius testified in relation to the bracing of the construction site. Bracing is a procedure where supports are put up to strengthen and reinforce structures - allowing them to handle particular weight loads.
With 45 years of experience in the industry, Pretorius, was hired by mall engineer Andre Ballack’s law firm.
He said he had conducted three or four structural investigations - particularly three shopping centre collapses.
He was tasked by Cox Yeats to investigate the likely cause of the collapse and to consider if any blame should be attributed to the design.
During a recent interview with the Daily News, mall developer Jay Singh had planted blame squarely on the engineers, claiming their oversight resulted in the collapse.
On Monday, Pretorius said the engineer was under pressure because the design of the mall was not completed at the time the contractor, Gralio, wanted to start construction.
Changes to the design, said Pretorius, were the origin of the problems on the site for the structural engineer.
“His plans must be done first, but he received the information last,” he testified.
He also said the changes to this R208m project were quite significant.
An example Pretorius referred to was the original layout of the mall being a simple grid layout, which then became complicated when beams were added to the design.
“Suddenly it was realised that they had to bring in delivery trucks to the storage area of the mall so the architect had to find a route to get these trucks through to these areas.
“To enable them to enter, columns had to be removed,” Pretorius explained.
He said the architect decided to remove columns and the simple repetitive flat slab grid system was gone.
Pretorius said beams then had to be introduced because the flat slabs had to be supported and expansion joints had to be added, which he said “made things even more complicated”.
Ballack is the next witness this week, along with Gralio’s engineer, Rob Young.
Singh and his son, Ravi Jagadasan, whose company Rectangle Properties, owns the land the mall is built on, have also been subpoenaed.
At the inquiry’s last sitting, engineers Ed Weakley and Gons Poonan testified.
Weakley was contracted by Ballack’s law firm to investigate the collapse and is also acting for Ballack’s insurance firm.
Poonan investigated the collapse for eThekwini Municipality.
Weakley had testified that he believed beam 7 was the cause of the collapse, while Poonan had concluded the cave-in started with column 243.
Engineers are trying to establish the trigger to the collapse – beam 7, and two columns, 243 and 319, have been identified as the three possible causes.
It was reported that Weakley said the beam was the weakest link as it had inadequate steel reinforcing with seven bars, and not 19.
Poonan had said the structure was unbraced.
Two workers, Zakithi Nxumalo and Zwelibanzi Masuku, were killed and 29 people injured when a concrete slab from a still partially built mall collapsed on November 19, 2013.
After the completion of the hearings, the commission is expected to prepare a report on its findings and formulate recommendations to be given to the labour minister and the director of public prosecutions.