Calibration of brick masonry partial safety factors for the South African Code

Abstract

The current South African Code of Practice for structural use of masonry uses four partial safety factors gm, for materials depending on construction control and quality control. With the boom in the construction industry, new entrants in the industry lack skills and the construction quality, particularly of masonry structures, is compromised. This has been proven by a number of structural failures and poor workmanship in the home building industry. However, the values of gm are based on the British Standards with some slight modifications to take into account local conditions. In this paper, focus is on establishing the reliability level as prescribed in the current code. The parametric calibration is based on current stochastic models and on statistical data collated by the National Home Building Registration Council (NHBRC) using a well researched quality assessment tool (Building Quality Index for Houses). Highlights are also made on the current work-in-progress in testing masonry walls so as to establish a South African material resistance stochastic database. The paper describes the format of the South African code, the stochastic models based on the test results and the resulting partial safety factors.