We were engaged by Mastrack Sdn Bhd to investigate the cause of blowholes and other defects associated with mechanical damage on the surface of pre-cast concrete railway sleepers for the Rawang-Ipoh Double Tracking Project. The Rawang-Ipoh Double Tracking Project was the first phase of the modernization programme of the rail network in Malaysia. The production of the sleepers was undertaken in a conventional manner using steel moulds placed in a continuous flatbed followed by concrete casting. The raw materials for concrete production were inspected on site and it was confirmed that river sand from Semenyih and granite course aggregates from Negri Roadstone were used for concrete production. The PSC sleeper production facility in Batang Benar, Mantin was well organised with the added advantage of a dedicated on-site batching plant for all the concrete supply.
Our analysis report and recommendations were submitted to Mastrak for consideration and provided a basis for understanding the problem and options for improvement.