This reason for the flyover collapse that could have killed many motorists seems highly unlikely unless the beams had been placed in position directly above each other; ie eight beams in a vertical pile.
If you study the photo (thanks to New Straits Times) you can see that the beams appear to be all on the same level and if a "Domino Effect" was the actual cause, some broken parts should have fallen on top of each other unless we are supposed to believe that the "Domino" forces had been acting horizontally.
Having observed the massive Causeway "improvement" project in JB, in most cases the beams are placed on the same level at different positions across the span so that the roads can be built over the beams to create the dual carriageway.
Many fingers are being pointed at the contractor about short cuts etc and perhaps they had a role in this near tragedy.
Perhaps they installed the concrete beams too soon after the beams were delivered. If I were to investigate this serious incident, I would obtain samples and also production/quality records of the firm supplying the beams as concrete has a curing rate that can affect the beam strength.
I would also check how the beams had been loaded on the transport vehicle and what type of vehicle had been used and also how the crane operators had hoisted the beams just before the mishap.
As you can see, many factors could have affected the beams' integrity.
"Domino Effect?" Naah....only if you believe in Cinderella.