One, the body shape of the house. The body shape of the regular, uniform, symmetrical house seismic capacity. Big on the bottom of the small head-heavy body shape of the house is called vertical irregularity, the plane of the local protruding L-shaped, "D" shape body shape is called plane irregularity, a head of heavy head of light is called torsion irregularity, irregular building seismic capacity are poor.
Two, the structural form of the house. Brick structure seismic capacity than reinforced concrete frame, frame - shear wall weak. The bottom of the frame on the upper brick, with the conversion floor of the house, the bottom of the open house, the slab-column system of the house seismic capacity are relatively poor. Weakness of the ground floor is easy to "sit" down.
Third, the construction quality of the house. According to the construction plans, technology in place, the quality of housing is good. Otherwise, the design is good, poor construction quality will be a problem.
Four, the house construction materials. Enough concrete grade, whether the steel is qualified, there is no cutting corners, etc. are very important.
Fifth, the construction age of the house. Earlier houses based on seismic standards are relatively low. Because of the level of understanding and financial growth, after the construction of the house seismic capacity is relatively strong. And so on!
China's seismic design code for buildings formulated after 1989, the goal of the defense requires buildings to do "small earthquake is not bad, the earthquake can be repaired, the big earthquake does not fall". The so-called "earthquake does not fall" refers to the earthquake, the actual seismic intensity than the seismic intensity of 1 degree to 1.5 degrees, the building should not collapse.
Where earthquakes occur in general is not known. And most houses have a life expectancy of 50 years, most of the country within 50 years most of the earthquake does not occur, but it can not be left unprotected, if the standard of defense is too high, and not earthquake, the financial resources invested is a waste of money, and we do not have that much financial resources.
China according to the importance of the function of the building will be divided into seismic defense standard A, B, C, D four categories. General houses are in category C. Stadiums with more than 6,000 seats, theaters with more than 1,200 seats, high-rise buildings with more than 10,000 people living or working in them, as well as bridges, airports, hospitals, elementary school, kindergartens, and projects that will cause serious secondary disasters if the building is damaged, such as nuclear power plants and warehouses of hazardous materials, have seismic standards that are at least one level above those of the surrounding buildings.
In addition, I remember our teacher also told us that when the Los Angeles earthquake occurred on January 17, 1994, there were two hospitals that didn't collapse. I don't remember the names of the hospitals (if anyone remembers them, please remind me in the comments), but one of the equipment inside was in disarray and couldn't be used at all, while the other was basically intact. After an earthquake, the consequences of not having medical equipment in a lifeline project like a hospital are unimaginable. Later, the investigation found that the hospital with intact equipment had adopted elastic seismic bearings for its foundation, while the other one did not. It can be seen, in the face of the power of nature do not always think of strong against strong, but should be soft to overcome.
A lot of words, back to your earlier question, the conclusion should be obvious. The stronger the foundation is, the more favorable it is for earthquake resistance, but it is by no means the only way to solve the problem of earthquake resistance, and it is by no means the optimal and most economical way.