Helensvale Rail Slab Inspection

Project No: 6915

Our Helensvale Rail project was a forensic inspection and 3rd party review of a slab which had exhibited cracking. The site contractors noticed some surface crazing post-pour; small cracks which widened substantially as time passed. Our site inspection found that the slab in question – the final concrete pour of five using the same concrete batch – had been delayed due to the possible onset of rain. The sub-base material was also sodden due to rain in the days leading up to the pour.

We found that the slab’s jointing was ineffective and the saw-through joints were too shallow, which resulted in shrinkage cracking. We also identified 3m long, hairline longitudinal cracking which may have been due to flexural stress due to trafficking across a weak/sodden sub-base or the tapered slab base on one side.