M.Sc Thesis

M.Sc StudentOffir Yaron
SubjectEfficient Earthquake Vulnerability and Damage Assessment of
Typical Residential Buildings in Israel
DepartmentDepartment of Civil and Environmental Engineering
Supervisors PROFESSOR EMERITUS David Yankelevsky
ENGINEER Stephan Schwarz


This research presents a new methodology for earthquake vulnerability assessment of a large inventory of existing buildings. It is of major importance for residential buildings in earthquake prone areas where a considerable seismic risk exists. There is a need for rapid, cost effective and reliable assessment of the capacities of the existing buildings, and to predict the damage that may develop as a result of a given earthquake scenario. This is essential for rational planning of many actions, such as the retrofit programs of existing buildings before the occurrence of a strong earthquake, allocation of rescue forces and equipment to optimally deal with the forecasted damage, and long term rehabilitation planning after the occurrence of a strong earthquake, etc. The proposed approach is based on a very limited amount of available data in a common GIS database. The additional needed data is derived from thorough examination of the topology of the layout of the buildings, together with supporting data related to local historical development, applicable codes and regulations, etc. Using this data, a "most likely" structural system is composed. The "most likely" structure is analyzed, in a special approximate non-linear manner, suitable for the uncertainty conditions of the input data. The first cracking, yield, and the failure points are found for the various members of the structural system. The member capacities are updated taking into account the increase or decrease in the axial force level, as a function of the external horizontal load level and the member location in the building layout. A special section deals with the significant influence of infill masonry. The overall capacity curve of the structure is obtained, emphasizing the sequence of the components failure. When the capacity and the demand are determined, the expected damage may be estimated for the entire inventory of these buildings, taking into consideration various earthquake scenarios.

The present methodology deals with existing residential buildings and can be extended to other types of buildings. The algorithms are integrated in a GIS database, to enable examination of large inventories of buildings. All the algorithms are developed in modular packages that can be modified or combined, according to various given sets of data, and can be used as "automatic" algorithms in a special purpose software. In this research an existing, common GIS data base of a small town containing 1600 buildings was used, to perform several sensitivity tests of the proposed approach.