By Yinka Kolawole
The recent collapse of a section of the Ikeja City Mall in Lagos has been attributed mainly to human error by some processionals in the built industry.

Past Chairman of the Nigerian Institute of Building (NIOB) Lagos State chapter, Mr Kunle Awobodu, on an assessment tour of the site, noted that carelessness and negligence on the part of the workers due to fatigue or other reasons could have been responsible for the mishap.

He said a close observation reveals that the collapse of the fresh upper floor slab was caused by failed centering made of thick timber boards supported by adjustable metal crow props and scaffolding, adding that the metal scaffolds which transmitted the loads from the props to the compacted filled lateritic soil rested directly on timber boards for stability purposes and to prevent inverted punching and unevenness.

According to him, the same centering method was adopted for the existing cast in-situ suspended waffle and solid slabs.

“We also recognise the fact that the existing slabs vary from 250 to 300 mm thickness and also includes a beam of over 800mm deep in Cinema hall area. This simply suggest that the centering was appropriate to carry a 250mm thick slab which was that of the collapsed slab.

“Except for two slightly bucked columns, the 32 mm diameter reinforced columns that connected the collapsed freshly cast beams remain intact,” he added.

Awobodu noted that construction was a team work and that any error committed by a member could sabotage the collective efforts of the entire work force. He emphasized that trained builders must possess keen observation to discover errors and ability for precision in construction, equipped with technical eye for details.

It would be recalled that a section of the massive building located at the sprawling Lagos State Secretariat area, Alausa,, being developed by Messrs Cappa & Dalberto, caved in recently when workers were still on site, with at least five people reported to be seriously injured.