Group flags below-standard steel bars used for high rises
A GROUP of concerned citizens has called for the recall of locally made steel bars which are claimed to be below standard for high rises, having been quench-tempered instead of being made with micro-alloy.
Former senator Anna Dominique L. Coseteng and structural engineer Emilio M. Morales said that for the past 10 to 12 years, local steel manufacturers have been replacing micro-alloy (MA) steel bars with quenched tempered (QT) or thermo-mechanically treated (TMT) steel bars, which are not fit to be used for high-rise buildings and undergo welding, bending, galvanizing, or threading given their less durable structure.
Ms. Coseteng said the steel bars must be recalled and released with proper markings.
“All steel bars still found in bodegas, warehouses, job sites and factories have to be recalled by steel manufacturers, bring them back to the factories, melt them down….[They must be] duly embossed and identified and put out in the market so people will know what they are,” she said in a press conference on May 31.
Identification of steel grade has also been changed by the Bureau of Product Standards (BPS) under the Department of Trade and Industry (DTI) to color marking instead of embossment. The public has not been made aware of this change, Ms. Coseteng said.
“The steel manufacturers deliberately, consciously, willfully kept in secret the fact that they removed the micro-alloy steel bars in the market and replaced them with quench-tempered bars,” she added.
The group said the bars also passed standards under the BPS because the BPS only tests tensile strength, involving only a subjection to controlled tension. They also cited conflict of interest.
“The people in charge of imposing standards in this industry, there is a conflict of interest…so how can we ensure that there is a proper standard in this industry and that this is being complied [with]?” Rodel Taton, president of the Consumers Union of the Philippines, said.
Mr. Morales said that based on his studies, QT rebars are not fit for high-rise construction particularly in seismic countries.
The QT rebars have brittle outer layer which will pass for Grade 60 steel, but the inner part will only reach Grade 40 after welding.
“The manufacturers cannot show proof…that their products are fit for seismic zone 4, where the Philippines is,” he said.
“They have not refuted, denied, or discredit our claims,” he added.
Mr. Morales said other countries which experience earthquakes, including Taiwan, Japan, and New Zealand, have established their own restrictions regarding QT bars. — Patrizia Paola C. Marcelo