How people should prepare for the 'Big One'

by Kathlyn dela Cruz, ABS-CBNnews.com

Posted at May 26 2015 10:53 PM | Updated as of May 29 2015 01:40 AM

MANILA - "Ano ang matibay na bahay?"

Everyone, including children, should be able to answer this question, according to Philippine Institute of Volcanology and Seismology (Phivolcs) director Renato Solidum.

In an interview on ANC's "Talkback with Tina Palma," Solidum said earthquake preparedness should start in an individual and his or her family.

He suggested that public and private schools teach children the materials and specifications necessary for a house to be earthquake-resilient.

"Ano ang matibay na bahay? Pwede yang ituro," said Solidum. Teachers can also assign their students to develop an earthquake evacuation plan along with their siblings and parents, he added.

"Preparedness should be evaluated through various lenses. One is individual and family awareness. We can only be safe if we do the right action," he said.

Local government units (LGUs) should also be prepared to respond to a disaster. Engineers, meanwhile, should help in checking the structural integrity of homes and buildings to make sure that these could withstand massive quakes.

"If people are sick, they go to the doctor. If they cannot afford the doctor, the doctor conducts a medical mission... Why not have an engineering mission?"

"We all have to be involved. Now," Solidum stressed.

STRUCTURAL INTEGRITY

According to the Phivolcs director, all houses and buildings, whether low-rise, medium-rise or high-rise, should be structurally designed to withstand a massive earthquake.

"Earthquake science would dictate that if the epicenter is near a settlement, the ground will shake fast. We call it high frequency vibration and that will move more the lighter buildings. The lighter buildings are obviously the shorter ones... But if the epicenter is far, the ground movement is low -- low frequency vibration. Then the taller buildings will sway more," he explained.

"That is why all types of buildings, short or tall, must be designed properly using the right materials," he said.

Phivolcs has released a 12-point questionnaire to help the public assess if their house is ready for a strong quake.

"There must be a good foundation," Solidum said, noting that structures should have a minimum of 6 inches of hollow blocks for the exterior wall and must be regular in shape.

Engr. Carlos Villaraza, president of the Association of Structural Engineers in the Philippines, also said the National Structural Code of the Philippines should be strictly followed by engineers, developers and contractors.

"Kasi if they follow that strictly, [a building] should not be damaged at intensity 8. At intensity 10, it can be severely damaged pero walang collapse," he told ANC.

"Ang mga developers naman they have to get good engineers... You have the social responsibility to take care of your clients or yung mga bibili sa inyo. And then the contractors have to follow strictly the plans. Huwag kayong mag-shortcut sapagkat malaki ang nakatayang buhay diyan," he added.

RELOCATION, RETROFITTING

Phivolcs recently released the Valley Fault System Atlas, a collection of maps that trace the 100-kilometer West Valley Fault which passes through Bulacan, Rizal, Metro Manila, Cavite and Laguna, and the 10-kilometer East Valley Fault that runs through Rizal.

According to Villaraza, small structures should be at least 5 meters away from the fault line while large structures should be at least 10 or 20 meters away.

Also speaking to ANC, Quezon City Mayor Herbert Bautista said they have already identified the homes located on top of the fault line.

The challenge now, he said, is how to persuade the informal settler families living on top of the fault line to leave their homes with no relocation sites available.

The mayor noted that the focus of the national government has been those living along the riverbanks due to the destructive typhoons that have hit the country in the past years.

"We are requesting the national government to address the issue aside from those in riverbanks," he said.

Bautista said there is also a need to retrofit buildings that are over 40 years old.

"Kasi paglagpas ng 40, nagsisimula nang mag-decline yung tibay ng mga gusali na yan. Parang tao rin, humihina na rin siya," he said.
Yung nakapaligid sa QC Circle, luma na yan. Yung City Hall mismo, luma na yan, magsi-singkwenta na yan."

"Eh ang problema si national government hindi naman niya pinopondahan yung para sa retrofitting eh. Kailangan meron talagang seryosong pananagutan yung pamahalaan, na mag-allot talaga ng pondo," Bautista said.