Kota Kinabalu: The Institute of Architects Malaysia or Persatuan Arkitek Malaysia (PAM) is concerned that incorporating serious earthquake measures in buildings throughout the state without good justification will hike up building costs.PAM Seismic Committee Chairman Ar. Arnold Kwan in his press briefing on 'Earthquake Design Code and its implications,' opines that "The construction cost will increase unnecessarily in the low risk zones which is covering most part of Sabah and it surely will not be in the best interest of the house buyers."Sabah is already known to be the most expensive place to own a house in the country and coupled with this new seismic requirement, it will make it even harder to own a house and the economic well-being of the state will also be adversely affected," he said.
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"The historical records show that most of the more serious earthquake with Richter scale above 5.0 to 6.2 occurred in Ranau and Lahad Datu zones."Whereas the rest of Sabah has not had any earthquake occurred in the past 60 years that was greater than 5.3 Richter scale."We have not seen any building collapsed due to earthquake during those periods but more stringent requirement may be imposed on Ranau and Lahad Datu zones," he stressed."In terms of PAM Sabah Chapter's position, we believe that public safety is of paramount importance but it must not be overdone for the sake of sustainability.
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"We supported the idea of seismic zonation recommended by Prof. Dr. Felix Tongkul, Professor of Geology and Head of Centre for Natural Disaster Studies at Universiti Malaysia Sabah (UMS) and Mohd Yusop Ramli, Deputy Director of Jabatan Mineral & Geosains Malaysia, Sabah branch gave an insightful presentation on facts and findings of the June 6 earthquake at Ranau.Kwan said that according to Prof. Dr. Felix, the underground gravity sliding near Mount Kinabalu has been there for a long time, stretching back thousands of years ago, with movement of a few millimeters every year.
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What triggered the recent earthquake was when this gradual almost unnoticeable sliding accumulated sufficient energy to overcome the threshold of restraint thereby releasing the release of energy and resulting in shock waves that caused the earthquake.Nevertheless, based on historical records, Prof. Dr. Felix is of the opinion that high magnitude earthquake such as the recent one is rare and will not happen frequently here, Kwan said, adding that Mohd Yusop Ramli of Minerals & Geo-science Department Malaysia also concurred with that opinion reaffirming that Sabah is very far away from the active zone of seismic activities, as compare with the "Ring of Fire" around the edges of the Pacific Ocean. Based on data gathered from the previous earthquake epicenters and major faults, the Minerals & Geo-Science Department Malaysia had divided Sabah into three earthquake zones namely, Central North Zone (Ranau), Labuk Sandakan Basin Zone (Labuk) and Dent Semporna Peninsula Zone (Lahad Datu).Subsequent to that, they had further divided these zones into micro-zones and these earthquake micro-zoning maps are set to be published by early next year.Mohd Yusop also said that from historical records, some regions of the earth are more vulnerable to earthquake than others thus is the basis of seismic zonation, Kwan explained.Furthermore, according to Prof. Dr. Felix, the proposal by IEM Technical Committee (KL) to blanket the Peak Ground Acceleration (PGA) reading of 0.12g as the Reference for the whole of Sabah for the Design of Earthquake Resistant Structures is not appropriate.The historical record of earthquake intensities in Sabah show varied figures from place to place. Obviously, it would be prudent to have a high PGA value of 0.12g at Ranau, but at Beaufort or Sipitang, the PGA value should by inference of previous seismic events, be much lower since the inhabitants there hardly felt any tremor during the recent earthquake.He further opined that experts such as the Minerals & Geo-science Department Malaysia Sabah Branch, the Meteorological Department (Sabah Branch) and the Centre for Natural Disaster Studies of University Malaysia Sabah should be involved in rationalizing for the micro seismic zoning as they would have the historical data to enable this exercise. His view was shared by Mohd Yusop of the Minerals & Geo-science Department Malaysia.On the impact of the recent earthquake in Sabah, Prof. Dr. Felix feels that there were over-reactions among the general public and sensationalist data from other non-Ranau seismic events being transmitted through social media.Nevertheless, he had visited most of the affected buildings such as schools, shops, banks and houses in Ranau and Kundasang where the epicenter is and found that the main structures of the buildings were not seriously affected.There were cracks on non-structural walls but not on floors which should be affected most in an earthquake. He also stated that deviations in quality of materials and workmanship may have resulted in such cracks.He quoted an example where only one panel of a row of fixed glass wall in a bank was broken instead of the whole row, signifying possible variation in the installations. He also said there were no reports on damages on buildings around the town area.Quoting words from a local Professional Engineer Ir. Michael Wong, Malaysia is in the process of adopting Euro code EC8 for the design of earthquake Resistant Buildings, with incorporation of National Annex for the Malaysia context.Under the global EC8, buildings of various classes are to comply with requirements of "No Collapse", and "Damage Limitation" requirements.The "No Collapse" requirement applies to class II buildings such as private houses, low-rise buildings like shops.This "No Collapse" criteria required that the buildings shall not collapse and result in casualty to human lives.It reckons that as earthquake is a rare event, the buildings are considered earthquake compliant even they are damaged beyond repair.Whereas for Class IV buildings such as hospitals, they shall be designed to "Damage Limitation" requirement that they and the sensitive instrument inside the building shall continue to function during and after earthquake without damage, thereby without jeopardizing lives of sick patients, operations can proceed during a seismic event and sensitive instruments are not adversely affected.The various Classes I, II, III & IV types of buildings are to be designed to various intensities of Designed PGA based on the "Referenced PGA" to be produced by the Minerals & Geo-science Department Malaysia (JMG).Ir. Michael Wong further highlighted that JMG's role in defining appropriate Reference PGA (peak ground acceleration) values for various zones in Sabah is of primary importance to development in Malaysia in General and Sabah in particular as too onerous provisions will have significant cost escalation effects to our economy. On the other hand, under provision can lead to compromise to safety versus seismic occurrences.Immediate past chairman of IEM Sabah Branch Ir. Tang led a team of Engineers to visit Seismic institutions in Taiwan where they have gained further in-sights on what has been recorded, researched and practiced under much more severe seismicity conditions.His opinion is also towards formulation of a varying range of RPGA for different parts of Sabah. These upcoming National Annex specified values to be used by structural engineers for design of new buildings and retrofitting of old buildings mean extraneous additional costs if excessive values are prescribed and adopted.Earthquake Design in EC8 also require factoring of the Reference PGA value to take care of building classes, heights, behaviours, underground subsoil conditions etc.The eventual Design PGA value can be very much higher for adverse cases of natural periods and poor ground conditions. During its Earthquake Seminar on 30th September 2015, IEM Technical Committee (KL) has presented its findings on additional structural costs for Sabah using the Reference PGA Value of 0.12g on regularly configured buildings of varying heights and under various subsoil conditions. It is found that the estimated additional structural costs vary from about 8.1 per cent for low rise to 64.6 per cent for a 10-storey building.The proposed Reference PGA Value of 0.12g is currently being debated among the local professionals, researchers, government officials and dialogs will be held with IEM Technical Committee (KL) to verify its validity and viability of blanket implementation to the whole of Sabah.PAM opines that micro-zoning with proper justification and upgrade maintenance of the zoning plan should be carried out as and when required through monitoring of seismic activity and fault lines.Ir. Michael Wong further stated that mention must be made also on the adverse impacts of over-provision on other architectural, engineering and construction related trades and not forgetting upgrading of existing buildings to achieve seismic resistance to the new requirements."On a worldwide front, PAM believes that such small countries as Taiwan, Philippines and New Zealand do have seismic zoning maps, so why shouldn't Sabah have it too. "The cost to construct a building in a higher risk area should be different or more expensive than those at the lower risk area. We acknowledge that, if the proposal by IEM Technical Committee (KL) to apply state-wide the PGA reading of 0.12g or 12 per cent g, it will has a very serious and negative impact to the construction industry in Sabah.Stay up-to-date by following Daily Express’s Telegram channel.
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