THE speeding trailer swerved, hit a van and a taxi and then ploughed into a lamp-post and trees at the centre divider of the Pan Island Expressway towards Changi Airport.

As if the damage wasn't great enough, the crash dislodged the six concrete slabs it was ferrying. They landed on both sides of the highway, causing a six-hour jam.

No one died in the crash on April 26 last year near the Adam Road flyover, but two people were injured and five vehicles damaged, including a van that was crushed by two slabs each weighing about 1,400 tonnes.

On Wednesday, Kane Ong Woon Chong, 26, was jailed six weeks, fined $1,200 and barred from driving for a year.

He had a faulty speed limiter, which would have stopped him from going beyond 50kmh. As it turned out, he was going at up to 70kmh, a police prosecutor told the court on Wednesday. He also drove dangerously and did not secure the slabs properly.

He said: 'The accused was driving a vehicle that is excluded from using the expressway as he was conveying his goods - concrete slabs - on an open trailer and not in a standard container.'

Heavy vehicle collisions that caused injuries and deaths have risen for the third year running, the Traffic Police told The Straits Times.

In 2006, there were 175 cases. This went up to 182 cases the following year and 259 last year.

Similarly, violations like speeding and dangerous driving by drivers of heavy vehicles have also increased with heavier enforcement.

Heavy vehicles like prime movers, trailers and tipper trucks have to observe speed limits of up to 60kmh.

Read the full report in Thursday's edition of The Straits Times.