Identification And Analysis Of Risk Factors Of Tower Crane In Construction Sites Of Super High-rise Buildings

Tower cranes is one of the main equipment used on the construction sites of high-rise buildings.Various loads are hoisted and transported in height,under rough working condition,delivery time pressure and other factor that influence tower crane operation.Though tower cranes bring enormous advantage to the construction process,yet they pose great safety risk to the site.This study was conducting in two phase.The first phase aimed at identification of safety factors and their degree of influence on the probability of occurrence of accident;the second phase of the study aimed at adopting a quantitative approach to assess the weight of factors.The first phase of this thesis present a result of study that aimed at identifying safety factors due to tower crane operation on the construction sites of high-rise buildings.Furthermore,the degree of influence to which each factor influences safety on the construction sites of high-rise buildings was evaluated,and the result of the degree of influence was then presented in histogram bar in ascending format.For the first of this study the adopted research methodology was based on comprehensive literature review,survey questionnaire and interview of expert team from three different companies that included safety directors,safety managers,and project managers.The second phase of this thesis aimed to adopt quantitative approach to assess the identified safety factors.At first an approach which would be able to elicit knowledge from experts and generate a set of weighted factors was necessary to be adopted.Hence,through comprehensive literature review and interview of experts that were working as safety directors,safety managers,and project managers at the time of survey,analytical hierarchy process(AHP)was identified as an appropriate multiattribute decision making tool.The experts were then requested to provide their assessment on the relative importance of each factor which was identified during the first phase of this study.After conducting analytical hierarchy process in five steps,the results is dominate by operator proficiency which shows the importance of operator's level of experience on the overall safety of the site.For the second phase of this study the methodology was therefore based on comprehensive literature review and interview of experts to identify a decision making tool which would allow to convert non-numeric data into a set of numeric weight of safety factors.Furthermore,these factors can be used for further studies to mitigate risk due to tower crane operation on the construction sites of high-rise buildings.