Seismic response of reinforced concrete buildings as predicated by the draft of Libyan standard (DSLS-1977) and (IBC-2009)

The draft of suggested Libyan Standard (DSLS-1977) is the only code of practice for designing and construction of earthquake resistant buildings in Libya, was first proposed by the Ministry of Housing in 1977, it is still used by Libyan engineers and several other foreign firms operating in Libya. The draft is suffering from many limitations and shortcomings, it has not been subjected to any development for a long period to be consistent with modern codes. DSLS-1977 divided Libya into 5 hazard zones and suggested a basic model for seismic analysis for regular buildings limited to 40 m high, suggesting linear elastic behavior of the building, and adopting the equivalent lateral force procedure associated with the fundamental mode of vibration for the determination of the resulting base shear force. The assessment and examination of the ability of DSLS -1977 for predicting an appropriate seismic forces for reinforced concrete building system was made by conducting a comparison study with the international building code IBC-2009. Special attention was made to the effect of soil structure interaction involved in the analysis when using IBC-2009 model on the resulting base shear.