On 14 Jul 2017, the incomplete Pan-Island Expressway (PIE) viaduct collapsed with 11 workers on top of it, injuring 10 of them and claiming the life of 31-year-old Chinese national Chen Yin Chuan.
Singaporean Leong Sow Hon, 61, the accredited checker for the viaduct project, pleaded guilty in court that for failing to check the detailed structural plans and design calculations of the viaduct building work by regulations under the Building Control Act.
Leong had failed to go through the detailed plans and design calculations for the permanent corbels or support structures, which are key in the stability of a viaduct.
Leong had initially claimed that he had performed the original calculations for the corbels and found them to be adequate. However, he admitted that he was lying after engineer Shivananni Yalagunda Siddalingaiah verified that there were no such calculations.
After the incident, it was found that the permanent corbels were inadequate.
Of the eight corbels, five were unable to support the weight they were supposed to be designed for, while the three other would have shown significant cracks with a full traffic load, which would lead to a collapse, said Deputy Public Prosecutor Yang Ziliang.
Another charge for falsely certifying that he had carried out the required checks was taken into consideration.
Leong is the first person involved to have plead guilty in this case. The rest are set to claim trial.
District Judge Hamidah Ibrahim adjourned sentencing to 5 Jul.