【明報專訊】TO tackle the construction problems of the platforms at Hung Hom Station of the Shatin-Central Link, the MTR has submitted a plan to open up the concrete at not fewer than 80 locations to inspect the connections between steel bars and couplers. The hearing by an inquiry commission looking into Hung Hom Station's construction problems has gone on for nearly a month and a half and many witnesses have given contradictory statements. The only way to find out the truth is to open up the concrete to inspect the steel bars. The government must ensure that platform safety is the first priority. It must not relax the requirements concerning the inspection of the steel bars for the sake of opening the Shatin-Central Link on schedule next year. The MTR has wasted a lot of time over the last six months because it has been trying to avoid opening up the concrete to inspect the steel bars. The plan to open up concrete at random locations as proposed by a team of the Hong Kong University commissioned by the government is more reasonable. The public has no way to judge whether the number of random checks is sufficient and can only put their trust in the experts. To ease public doubts, the government's Expert Advisor Team for the Shatin-Central Link Project and the HKU experts can provide more explanations. If the initial inspections show that the problem is severe, the sample size should be expanded.
For a long time, the MTR has not been facing squarely the problem of shortened steel bars at the platforms of Hung Hom Station. Initially it proposed only to test the loading capacity of the platforms. It was only when the government found out that the MTR investigation report had not been telling the whole truth that it was decided that the concrete must be opened up for the inspection of the steel bars. However, the MTR tried to muddle through. Last October, the company submitted a test plan and proposed to open up the concrete in only 10 places of the platform slabs along the east-west corridor to examine the coupler connections. The Expert Advisor Team appointed by the government rejected the plan on the grounds of its narrow scope.
The "shortened steel bars" saga has compromised the credibility of the MTR. The recent plan will ease the public's doubts because the locations for inspection will be selected randomly and independently by experts from the HKU rather than allotted by the MTR or the government. The MTR has emphasised that the locations will be selected by means of the internationally established method of random sampling and that it is a stringent sampling method. Some civil engineers think that the sampling density is acceptable while others think that the sample size is too small.
Sampling in statistics and opening up concrete to inspect the steel bars both require professional knowledge. Ordinary citizens do not have the knowledge and can only put their trust in experts. If the government's Expert Advisor Team for the Shatin-Central Link and HKU's engineering experts who designed the random inspection explain the plan in layman's terms, it will help to ease the public's doubts. The government and the MTR should also consider publishing an interim inspection report to inform the public of the preliminary results of the inspection. If it is found that the problem of fabrication is severe, the scope of inspection should be expanded to ensure that the final findings of the inspection are credible.
There have been a lot of problems in the construction of the platforms at Hung Hom Station. Opening up the concrete to inspect the steel bars is the only way to salvage public confidence. Even if it is found later that the process of inspecting the steel bars is more complicated and time-consuming than anticipated, the authority should not rush to conclude the structural assessment exercise for the sake of opening on schedule the Tai Wai to Hung Hom Section in the middle of next year. If the inspection proves that there have been severe violations of rules in the construction of the platforms, the government must find out who is culpable and make them pay compensation. Whether it is the MTR, the contractor or the sub-contractors, none should be allowed to get away with it.
squarely : directly or exactly; without confusion
muddle through : to attain one's object by good fortune rather than good management
culpable : responsible and deserving blame for having done sth wrong