April 25, 2019
THERE is no escaping natural disasters, but we can do everything in our power to safeguard human life. A 6.1-magnitude earthquake surprised everyone when it struck Pampanga and shook areas of Luzon and Metro Manila last Monday; then another earthquake hit Samar last Tuesday afternoon. A building collapsed while several buildings were seriously damaged, people were evacuated, a number were injured, and lives were lost. Imagine if the Big One happened tomorrow. Imagine any of the 18 disasters that could occur in our city. There are 10 man-made and eight natural disasters, and earthquakes are only one of them. We live in cities plagued by the ills of poor urban planning and construction design practices, and we work in a country that is susceptible to natural and man-made disasters. Hence, we — architects, engineers and urban planners — must review what we can do to be more resilient and to minimize potential damage.
Our studies, research and experience have shown that it will be 90 percent less expensive to address hazards before they become disasters, so we must manage them on time to save human lives, infrastructure and buildings. Let us also keep in mind that being informed, prepared and vigilant citizens is very important.
The “Study for Earthquake Impact Reduction for Metropolitan Manila in the Republic of the Philippines” done by the Japan International Cooperation Agency (JICA) in 2004 predicted what could happen if a 7.2-magnitude earthquake were to occur in Metro Manila. Around 170,000 residential houses would be heavily damaged or collapse, and 26 percent of buildings would be moderately damaged. The death toll in the first hour could reach 34,000 people and another 20,000 could become casualties in the succeeding hours because of fires and successive tremors that would occur.
In the event of the Big One, rescue activities will be limited. As it is, it takes two hours to travel 5 kilometers on an average day in Metro Manila, but with buildings and electrical posts down, thousands of homes on fire, and debris all over, it would take rescuers longer to reach the devastated areas. This is also assuming that our government forces and volunteers are safe and equipment are intact and operational. According to an international assessment, help would come after 72 hours, but because of Metro Manila’s urban sprawl and poor urban design, it is expected that it would take more time.
We in the planning, architecture, engineering, and design professions and in the building industry have the responsibility to design and plan the built environment to withstand environmental hazards and for it to last for as long as possible. When designing buildings, performance-based design should be used, a component of which would be to implement an “under reinforced system” on the structural design of an establishment to see the cue of failure or cracks on the concrete before it reaches its maximum tolerable stage. We must always follow technical specifications. We should undertake routine inspections and structural audits for all buildings and, in particular, for old ones in our cities to determine how structurally safe or hazardous they are. If it is determined that they are unsafe, they must be structurally retrofitted or demolished. Here are some measures, among others, that we can take to prepare for disasters in the best way possible:
Old structures that fail structural audit should be retrofitted or demolished, except those with historical value.
Government should check the quality of reinforcing steel in the market. Continuous bending of weak steel bars during quakes will place the building at risk.
Strict compliance with structure design plans and specifications should be implemented. Avoid cost-cutting in materials and labor.
Structural design of houses, buildings, bridges towers, etc. should be performed by reputable architects and structural engineers, not by fly-by-night, inexperienced designers.
Geotechnical reports are important to mitigate issues on liquefaction in the foundation designs of buildings. Pile driving should be considered.
Concrete strength of our airport runways should be checked and monitored. Low-strength concrete will result in wide cracks during quakes.
Government should increase the salaries of city engineers/architects, similar to the police pay hike, to eliminate red tape on project evaluation and inspection.
Upgrading of the Structural Code of the Philippines should be done to prepare for the Big One.
Almost exactly four years ago, on April 25, 2015, a 7.8-magnitude earthquake devastated Nepal, which took the lives of 9,000 people and injured nearly 22,000 others. Multi-story buildings located in its capital, Kathmandu, collapsed. After several aftershocks and another major quake, thousands of people lost their homes and livelihood, leaving them in extreme poverty and deprivation.
When my colleagues and I went to Kathmandu in January of 2016 to present our plans for rebuilding school campuses and hospitals, we saw firsthand that Kathmandu was still suffering from the damage months after the devastating quake. There, we designed a university, hospital and school to last 1,000 years. At Palafox Associates and Palafox Architecture Group, we recognize that we all merely borrow the environment from future generations. Our actions, plans and designs are geared toward enhancing the environment and studying the negative impacts to it. In little and big ways, each one can also do the same to make the Philippines safer and more sustainable.
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