THE Department of Trade and Industry (DTI) debunked the allegation of a former senator that locally made steel used in dozens of public infrastructure projects is of low quality standard.
In a news statement issued on Monday, the DTI belied the claims made by former Sen. Anna Dominique Coseteng of substandard quenched and tempered steel. The former lawmaker last week warned the use of QT steel in the construction of high-rise and sensitive buildings is risky and might lead to accidents.
“The DTI finds no factual or technical basis to support the allegation that quenched and tempered steel is unsafe for high-rise construction, following a series of consultations conducted with the Philippine Constructors Association, Philippine Iron and Steel Institute, Association of Structural Engineers of the Philippines and other relevant stakeholders. It was learned in the studies and researches made by the DTI that the process of quenching and tempering steel is being used by more than 190 countries across the globe for the last 30 years,” the DTI said.
According to the trade department, Coseteng’s allegation holds no water that the processes of butt-wielding, treading, hot-bending, galvanizing and heating of QT steel can result to damage of property. It cited a study by the Department of Science and Technology-Metal Industry Research and Development Center (DOST-MIRDC) that claimed rebar process through quench-tempering treatment passed all the chemical, physical and mechanical requirements.
“The said study also indicates that a QT steel bar, when heated up to a temperature of 500 degrees Celsius, does not impose any change in its microstructure. Although this exceeds the restriction set at 275 degrees Celsius in the National Structural Code of the Philippines 2015 edition, the DOST-MIRDC explained that this may be a very conservative cap on welding temperature to ensure safety,” the DTI added.
Steel groups also said butt-wielding is not even used for construction, and that galvanizing is never performed on rebars, as claimed by Coseteng. “In terms of treading, or the process of creating a screw tread to mechanically connect two rebars, some local steel manufacturers said that they perform roll treading to do this.
“They explained that this process only diminishes about 0.1 percent of the steel bar, which does not at all affect the strength of the rebar. This practice is also commonly used in the construction industry across the globe, including high-rise construction,” the DTI said.
The trade department vowed it will strongly uphold the use of QT steel bars, but will be watchful in maintaining the quality of materials being used by the government for its infrastructure projects. Unless steel groups and research proved otherwise, the DTI said the use of QT steel in high-rise buildings is allowed.
“In addition, massive information and education campaign on steel bars will be conducted for the benefit of consumers, constructors and all other concerned industry practitioners. The DTI continues to ensure quality and safety of products, particularly construction materials used in the golden age of infrastructure with the national government’s ‘Build, Build, Build’ program,” the DTI said.
Coseteng, along with Emilio M. Morales, former chairman of the Association of Structural Engineers of the Philippines, said QT steel bars will fail prematurely in incidents of cyclic loading, such as earthquakes, as compared to micro-alloyed steel. The two also said QT steel might have passed governments tests, but argued these tests are not comprehensive.
Image credits: Nonie Reyes