how to reinforce and strengthen the buildings in world cities located within earthquake zones?

2 comments

1. 

   Mountainboy19682 on December 8, 2009 at 2:13 pm

   Some things have to be done before the building is built. The worst damage in the 1989 Loma Prieta earthquake was caused to houses built in San Francisco on unconsolidated fill. Buildings made from masonry or stone blocks are also very vulnerable, which explains why so many third world earthquakes are so expensive in human lives. Reinforcing with steel ties helps keep masonry or stone walls together.

   None of this helps if you already have a building, or a city, built from bricks or stone on fill material. But there are some things you can do, and they mostly involve trying to make sure that things don’t break free when shaken. Below is a list from the USGS.

   Structurally Secure Your Home
   Step 1 Find out if your house is bolted to its foundation. If your house was built after 1935, chances are it is. If your home is older, you can have your house inspected and install bolts if necessary.

   Step 2 Make sure your chimney is soundly attached to the structure of your home. Collapsing chimneys are one extremely dangerous outcome of an earthquake. If your home was built before 1960, you may have to have it reinforced.

   Step 3 Have shear walls installed if your home was built on a raised foundation. Older houses often have cripple walls in the crawlspace between the foundation and the floor. To earthquake proof your home, you’ll need shear plywood reinforcement.

   Securing Furniture and Appliances
   Step 1 Bolt down the water heater. This will help prevent gas leaks.

   Step 2 Equip all cabinets with child-proof latches. This includes kitchen cupboards and medicine cabinets. These latches are cheap, easy to install and keep the contents of your cabinets from flying during an earthquake.

   Step 3 Store the heaviest objects, along with hazardous materials, in floor-level cabinets.

   Step 4 Secure tall furniture and hanging picture frames to the wall. Bolts will keep heavy furniture against the wall, as will Velcro installed at the corners. Pictures will probably stay put if you use a security hanger to keep them in place.

   Step 5 Place your T.V. on a lower, sturdy stand. It shouldn’t be perched on anything too small.

   Step 6 Move beds out from under windows. Ideally, a bed should sit against the room’s inner wall, which is the most stable.

2. 

   Rouse on December 8, 2009 at 2:13 pm

   Structural engineers and materials scientists are doing a pretty good job today. Traditionally, buildings were built as rigid as possible, but this caused the structures to concentrate siesmic loads in small areas and to fracture and fail in a siesmic event. Buildings are now designed with a slightly flexible or elastic structure. This design feature allows the enormous forces that transmit from the displacement of the earth to the relatively small foundations in high rise buildings, to be dissipated by allowing the motion to be distributed into all parts of the structure.