| Abstract: | Following the destructive Bam earthquake of 2003, the Iranian government initiated a vast program of seismic retrofitting for existing school buildings throughout the country. As a result of the school retrofitting program, an extensive amount of field test data is available on the shear strength of brick walls of buildings from different parts of the country having different climates. A large portion of the available data is utilised in this paper to determine the effects of environmental conditions, particularly those of humidity and temperature, on the shear strength of brick walls. The effects of other factors including the type of material and age of the building are also investigated. Results of the statistical analyses highlight the important effects of the location humidity level. A nearly three folds increase in strength was noted for walls constructed of solid brick units in wetter northern parts of the country compared to those constructed in the drier central parts. Another important factor is found to be the absorption rate of bricks used in constructing the wall. On the other hand, the effect of overall environment temperature is found to be minimal. The daily temperature gradient of the location, however, may affect the strength by causing some long-term fatigue. It is recommended that for assessing the vulnerability of unreinforced brick walls, regionalization is considered and an appropriate ‘climate factor’ is adopted. |
