Inquiry
Many potential causes of the accident were investigated. Surviving sections of concrete were tested to ensure they were to proper construction standards, and it was found that they were. Even the construction work of the underground railway tunnellers who had assisted in the rescue was investigated, even though the excavations were more than 100 yards from the collapsed building. It was found they had no effect on the building's stability.
Also investigated were the various additions made to the building after its initial construction. Air conditioning systems had been constructed on the roof of the building, the bank had added a large safe, and ceramic tiles had been fixed to the building's exterior, all adding considerably to the building's weight. It was found that the weight of these additions was inconsequential.
However, this line of investigation into weight led to the discovery that the original structural engineer had made a serious error in calculating the building's structural load. The structural engineer had calculated the building's live load (the weight of the building's potential inhabitants, furniture, fixtures, and fittings) but the building's dead load (the weight of the building itself) was completely omitted from the calculation. This meant that the building as constructed could not support its own weight. Collapsing was only a matter of time. After three different supporting columns failed in the days before the disaster, the other columns—which took on the added weight no longer supported by the failed columns—could not support the building.[12]
According to Channel New Asia, Lian Yak Building was designed by a unqualified draftman instead of professional architect. Investigator found that he had under-estimated the dead weight which the columns and walls could support. The draftman claimed that the building owner Ng Khong Lim, who eventually died in the collapse incident, had appointend him to design Lian Yak Building but Ng directed that building work. Investigator also found that Ng requested to use inferior materials to build Lian Yak Building for reducing the cost.
Sound detectors were used to locate survivors beneath the slabs by picking up faint moans and cries. In the first 12 hours, nine people were rescued. At one time, Lieutenant-Colonel Lim Meng Kin (SAF Chief Medical Officer), along with several other SAF medical officers and two doctors from the Health Ministry, took turns to crawl through narrow spaces inside the rubble in an effort to provide assistance to trapped survivors, giving glucose and saline drips to them.
Tunnelling experts from Britain, Ireland and Japan who were involved in nearby construction for the (Singapore) Mass Rapid Transit, including Thomas "Tommy" Gallagher, Thomas Mulleary, Patrick "PJ" Gallagher, Michael Prendergast, Michael "Mickey" Scott, and Tan Jon Thong, offered to assist.[10] They became concerned the use of heavy machinery would collapse the rubble onto those trapped. Their voluntary efforts, digging 4 tunnels under the rubble, resulted in the rescue of another eight survivors. The tunnelling experts were later honoured by the Singapore government for their efforts. Thomas Mulleary was also nominated for an O.B.E for his rescue work but refused the prestigious honour when the rest of rescue squad were not included.
After the five-day rescue operation, 17 people were rescued, but 33 people lost their lives. The last survivor, 30-year-old Chua Kim Choo, was rescued on 18 March 1986, having survived after hiding beneath a table.[11]