Earthquake Masonry Wall To Concrete Floor Slab

The second floor diaphragm with concrete topping is assumed to act as a rigid diaphragm and distributes the earthquake load to the walls in proportion to their stiffness.

Earthquake masonry wall to concrete floor slab.

They transmit the vertical dead load and live load to the bearing walls. The walls of this type of masonry are confined by concrete tie beams and tie columns to ensure satisfactory earthquake performance. Roles of floor slabs and masonry walls. The walls act as bracing panels which resist horizontal earthquake forces.

However if the house is not bolted to the slab you have an earthquake weakness. Floor and roof systems for use with loadbearing structural concrete masonry walls serve three primary functions. They function as diaphragms transmitting lateral wind and seismic loading through the walls to the foundation. The best solution is to either replace the masonry altogether especially if it is old and weak or to fill it in with concrete.

Masonry foundations are common throughout the united states and around the world. At the brick wall to floor slab interfaces which will result in cracking of the brick walls at adjacent mortar bed joints. Unfortunately these foundations are liable to break and collapse during an earthquake. Though this is a task that is more complicated than simply laying new block on the slab as it requires a higher level of thought and preparation.

The engineer should confirm these assumptions by comparing the in plane deflection of the diaphragms to the lateral displacement of the walls. It can be used to resist seismic loads if necessary measures are considered. Nearly all homes with slab foundations that were originally built to code will have anchor bolts or straps. 2002 for calculating earthquake forces b indian concrete code is 456 2000 for design of rc members and c ductile detailing code for rc structures is 13920 1993 for detailing requirements in seismic regions.

The walls in the confined masonry act as the bracing panels which resist horizontal earthquake forces. Flexible floor slabs are commonly used to connect different cantilever masonry walls. In effect this cracked mortar bed joint becomes a slip joint with questionable resistance against horizontal earthquake shear forces. Masonry walls transmit the gravity load from the slab s above down to the foundation.

And they act to support the walls from out of plane loads. Masonry walls transfer the loads of the upper slabs to the foundation successfully. It is much easier than one might expect. These houses do not have crawl spaces and cripple walls.

Some homes are built directly on concrete slabs. Providing a conventional slip joint metal strips with grease.