Factors Causing Structural Damage in Earthquakes

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What is one of the main factors that causes structural damage during an earthquake?

The duration of the earthquake

The type of soil at the site

The strength of shaking (correct)

The location of the epicenter

How does the strength of shaking decrease with distance from the epicenter for small earthquakes?

It remains constant regardless of distance

It decreases exponentially with distance (correct)

It increases with distance

It decreases linearly with distance

For large earthquakes, how does the strength of shaking decrease?

It decreases in a direction away from the fault rupture (correct)

It decreases towards the epicenter

It decreases uniformly in all directions

It remains constant regardless of location

What factor determines the length of shaking during an earthquake?

How the fault breaks during the earthquake Signup and view all the answers

During the Loma Prieta earthquake, how long did the maximum shaking last?

10 to 15 seconds Signup and view all the answers

Which of the following is NOT mentioned as one of the four main factors that cause structural damage during an earthquake?

The distance from the fault rupture Signup and view all the answers

What is a key characteristic of a soft story in a building?

Is unable to provide adequate shear resistance during an earthquake Signup and view all the answers

According to the National Information Service for Earthquake Engineering, what is the recommended method of retrofitting a structure with a soft story?

Installing proper shear walls or bracing to the soft stories Signup and view all the answers

What occurs in a building when pancaking happens during an earthquake?

The floors collapse, compress, and stack on top of each other Signup and view all the answers

Why do buildings with soft stories need to be retrofitted, according to the National Information Service for Earthquake Engineering?

Due to inadequate shear resistance or ductility during earthquakes Signup and view all the answers

What is the consequence of a soft story collapsing during an earthquake?

Total failure of the overlying floors Signup and view all the answers

In terms of earthquake safety, why are shear walls or bracing added to soft stories during retrofitting?

To provide additional shear resistance and ductility Signup and view all the answers

What causes torsional forces to be induced into the building frame during an earthquake?

Center of gravity twisting about the center of rigidity Signup and view all the answers

What is the primary reason for the collapse of the second story in the Hotel Terminal during an earthquake?

Torsional shear failure of the second-floor columns Signup and view all the answers

Why were the lateral reinforcements (ties) in the columns of the Hotel Terminal insufficient during the earthquake?

They were placed at inadequate spacing Signup and view all the answers

What effect did the torsional rotation of the upper part of the building have on inter-story drift?

Caused significant lateral displacement to the right Signup and view all the answers

In the example described, what was noted about the top and bottom sections of a collapsed column in Hotel Terminal?

They were side-by-side after collapse Signup and view all the answers

What was the significance of lateral reinforcements (ties) in resisting shear forces during the earthquake?

They were insufficient due to inadequate spacing Signup and view all the answers

What is the main difference between the Yerba Buena Island seismograph location and the Treasure Island seismograph location?

Yerba Buena Island seismograph is on rock outcrop, while Treasure Island seismograph is under sandy soil and bay mud. Signup and view all the answers

Which site experienced a peak ground acceleration of 0.16g in the eastwest direction?

Treasure Island Signup and view all the answers

How many times greater was the peak ground acceleration at the soft clay site compared to the hard rock site?

What contributed to the damage of structures throughout the San Francisco Bay area?

Amplification of peak ground acceleration by soft clay Signup and view all the answers

Which part of the Interstate 880 highway collapsed and was underlain by San Francisco Bay mud?

Northern portion Signup and view all the answers

What was the peak ground acceleration in the eastwest direction at Yerba Buena Island?

$0.06g$ Signup and view all the answers

What can create a soft story condition in a building?

A discontinuity in the shear walls from one floor to another Signup and view all the answers

Which of the following factors contribute to the resistance of single-family wood-frame structures to collapse during earthquakes?

Their flexibility, strength, and light dead loads Signup and view all the answers

What is generally recognized about single-family wood-frame structures that include shear walls in their construction?

They are very resistant to collapse from earthquake shaking Signup and view all the answers

Which statement best describes the resistance of wood-frame structures to collapse during earthquakes?

There are exceptions to the general rule that wood-frame structures are resistant to collapse Signup and view all the answers

Which factor does NOT contribute to the resistance of wood-frame structures to collapse during earthquakes?

Their heavy dead loads Signup and view all the answers