Earthquake Survival quite literally begins in your own home. To ensure safety against tremors, it’s important to assess your living space to know what types of repair and reinforcement it needs to be quake-resilient.
You can begin your home inspection by examining two major factors: its content and structure.
Securing House Contents
It is important to identify the items that can possibly move, break or fall when a quake jolts your house.
Things to remember:
1. Secure hanging fixtures on the wall and ceiling.
2. Strap down hazardous electrical components.
3. To prevent tipping, heavy and tall objects such as appliances and cabinets must be anchored or braced using a flexible fastener like a nylon strap and a hook.
4. Place the fragile, large and weighty objects on the lower shelves of cabinets.
5. Lock the cabinets if possible.
6. Rearrange large things including framed pictures and mirrors away from seats and beds to prevent injury to occupants when ground shaking occurs.
7. Ensure elastic connector on gas stoves or appliances.
8. Check the accessibility of fire exits.
9. Know when and how to shut off utility lines.
Checking Home Integrity
According to the Metro Manila Earthquake Reduction Study (MMEIRS), 38.3% of residential buildings in Mega Manila might be damaged when the Valley Fault System moves. 339,800 of them will be partly disrupted while 168,300 will be heavily dented. Unlike other hazards, quakes can transpire anytime without warning, bringing secondary dangers such as fire, liquefaction and ground rupture among others.
This study led PHIVOLCS in coming up with a checklist that homeowners can use in assessing how their Concrete Hollow Block (CHB) house will fare in the event of a strong quake. This checklist is applicable to 1- and 2-storey houses, and a must for houses built before 1992 when the earthquake resistance standards were introduced to the Building Code.
Evaluation will be based from the tally of scores from the 12-point checklist:
0 – 7: Assessment is disturbing and needs consultation with experts as soon as possible.
8 – 10: House requires strengthening and expert consultation.
11 – 12: Seems safe but needs confirmation from experts.
PHIVOLCS recommends consulting with a licensed architect or civil engineer and a licensed contractor for official assessments. Aside from further renovation, checking your foundation for cracks must be done whenever there are interferences— natural or manmade— that happened in your area.
Building a Quake Resilient House
1. Have a licensed civil engineer or architect supervise the building of your house to ensure compliance to Building and Structural Codes.
2. Construct a regular-shaped house on a rock or stiff soil. Avoid building structures on muddy and reclaimed lands.
3. Use 6-inch thick concrete hollow blocks.
4. Vertical bars should be 100 mms. in diameter and must only have a 40-cm gap in between.
5. Horizontal bars must be 10 mms. thick and spaced between 3 layers of CHB.
6. Walls more than 3 meters wide have to be reinforced.
7. May need to add more foundation.
8. Use light materials on gable walls. Gable wall is the triangular area that connects the roof and the wall. Or better yet, build a flat roof house.
It sounds like the apocalypse, but it’s true: a killer earthquake may or may not come in this lifetime, causing thousands of deaths and massive destruction in Manila. Find out what will happen when “The Big One” arrives.
Fault Finding: The Huge Earthquake that’s Waiting to Happen
The Philippines is positioned within the Pacific Ring of Fire, where high seismic activities such as volcanic eruptions and earthquakes occur. Apart from the active faults traversing the country, there are 23 active volcanoes that can also generate earthquakes.
On October 15, 2013, a 7.2 magnitude quake jolted Central Visayas, resulting into 222 deaths and destroying over 73,000 houses in less than a minute. With the seismic activity equal to the explosion of thirty-two Hiroshima atomic bombs, the provinces of Bohol and Cebu declared a state of calamity.
Greater Metro Manila Area (GMMA) is not exempt from earthquakes due to the very ripe West Valley Fault. Its 90 to 100-kilometer length crosses Rizal, Marikina, Quezon City, Pasig, Makati, Taguig, Muntinlupa and Laguna. Moreover, 35% of the population inhabiting the said areas lives right above this fault line.
The last recorded movement of the West Valley Fault was more than three centuries ago, in 1658. According to the Philippine Institute of Volcanology and Seismology (PHIVOLCS), a fault line usually moves sometime between two hundred to four hundred years. The movement of the fault is predicted to have a horizontal friction in between plates or what geologists call an “essentially strike slip.” The anticipated killer quake has been dubbed as “The Big One,” which can produce a magnitude 7.2, putting the capital’s population of over eleven million people at risk.
If the epicenter of the major quake hits Metro Manila with an intensity of 8 or 9, three million people would need to be evacuated; an additional 18,300 may perish due to fires in 97,800 buildings throughout the metropolis; 7 bridges would collapse, and secondary hazards such as liquefaction and landslide would also pose risks.
According to the United Nations, our country may lose as much as 19 percent of its urban-produced capital in such an earthquake, suffering economic losses of more than 9 billion US dollars. While, NDRRMC projects 2.3 to 2.4 trillion pesos or 10% loss in our Gross Domestic Product (GDP).
As always, the key to surviving calamities is knowledge and preparedness. Here’s how you can protect yourself before, during, and after earthquakes. https://www.youtube.com/watch?v=Gy8-dBTP3-Q