High Rise Building Construction Safety Risk Modelling in Addis Ababa

Abstract

With an increase in number of high-rise buildings in Addis Ababa, safety issues are becoming a main concern as construction of high-rise buildings is more risk prone than conventional buildings. Safety risks related to the construction of high-rise buildings has not been identified and prioritized along with the determination of which construction phase is risky. Moreover, there has been a lack of research that separately studies foreign contractors’ held and local contractors’ held construction sites. Past studies have been focusing on evaluating and/or assessing the existing safety practices of contractors. They failed to identify and prioritize the most important safety risks and which construction phase is more likely exposed to these safety risks and compare it between local and foreign contractor held construction sites. The aim of the study is to prioritize safety risks and determine the most risky construction phase using Analytical Network Process (ANP) modeling technique and compare the result between local and foreign contractors held sites in Addis Ababa. The results show that in case of local contractors; Sub-structure phase is the most risky phase and falling from height, falling objects, slips, trips, and falls, and trench failure/excavation accident are the top four most important safety risk factors. In case of foreign contractors, super-structure is determined to be the most risky phase and falling objects, falling from height, slips, trips and falls, and trench failure/excavation accident are the top four most important safety risks. These shows that much of safety related risks happen most likely during sub-structure phase in local contractors’ case and in case of foreign contractors it is super structure phase that is most likely exposed to safety related risks. Moreover, new safety risks that are prevalent in Ethiopian context have been identified from literature, i.e., caught in between/compressed by equipment or objects, repetitive motion, and manual handling are identified in this thesis. The results can be used by safety managers and/or their team to focus on these safety risks and these construction phases to minimize them to a certain degree to better manage safety before any loss or damage had happened.