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Abstract The October I tit, 1992 earthquake (5.8 Richter) that shook a large area of North Egypt and led to a considerable loss oflife and the collapse of a large number of buildings was a warning for engineers and seismologists. This warning was confirmed by the earthquake of 22nd of November, 1995(5.7 Richter by Egypt’s Helwan observatory) which was centered in the Gulf of Aqaba. In addition to that, an earthquake occurred in the 10°’ of October, 1996(6.8 Richter) and was centered in the Mediterranean sea to the north of the Egyptian shores and at 20 miles southwest of the Cypriot port of Paphos. These quakes pointed out that the long-held belief that Egypt is a low seismic risk zone no longer exists and thus the occurrence of an earthquake is a considerable probability The main problem is that the earthquake loading design forces were rarely mentioned or considered in the official material codes until recently. Besides, of the present official material codes, The Egyptian Code Of Practice Steel Structures And Bridges(ECSSB) of 1989(1) does not address the subject of earthquake effects to any extent. However, The Egyptian Code For Soil Mechanics And Foundation Design And Execution(ECS)(2) of 199 I includes detailed seismic design provisions. In the meantime, The Egyptian Code Of Practice For Reinforced Concrete Design And Construction (ECRC) of 1989(•1) covers the subject only in chapter 10 which is devoted to ”loads”. In addition, The Egyptian Code For Calculation Of Loads And F orces( ECL) of 1994 HI presented revised provisions for the calculation of seismic forces on structures Consequently, almost all buildings existing until 1989 are not designed to resist earthquakes. The first objective of this thesis is to study the seismic behavior of the already existing reinforced concrete and steel structures under earthquake excitation. The second objective is to compare the seismic performance of these two types of structures if they have similar geometrical shapes and design conditions. To achieve these objectives, a series of steel and reinforced concrete framed structures are analyzed. They are designed to represent several types of design procedures for buildings existing in Egypt. Three different groups of design procedures are examined In the first one, all framed structures are designed to resist gravity loads only While in the second group, they are designed to resist gravity and wind forces. In the third one, buildings are assumed to be located in the highest seismic zone of Egypt and designed to resist gravity and seismic forces( Alexandria area for instance). Then the behavior of these designed structures are evaluated when subjected to several degrees of severity of earthquake forces. The seismic forces is calculated according to the ECL(4)-1994 and ECRC(3) -1989. |