Weather Influence On Schedule Of Construction Projects

Large construction projects are with long period and complex construction environment, so their schedules are easily influenced by the weather and other factors. If managers are lack of knowledge about weather impact or scientific methods of risk control methods, the planned objects can not be realized and the schedule will be delayed. Control on schedule delay risk is a very important part of project risk management. To avoid the phenomenon of schedule delay, schedule risks of construction projects should be effectively managed. This paper has an exploration on the identification, risk modeling, risk assessment, risk control of the meteorological interference factors which affect the construction schedule. Based on literature review and investigations, taking a large road and bridge projects in Changsha as an example, this paper studies the identification, modeling, evaluation, control on the interference factors and the main results are as follows:First, in the risk identification stage, it defines the major meteorological interference factors at the construction stage through literature statistics and field survey. In the simulation, analysis and assessment stage, in the light of the historical meteorological data provided by the Hunan provincial weather station and Changsha municipal weather station, it uses Monte Carlo simulation technology to evaluate its distribution regularity and probability value, and provides the quantitative data of risk interference factors.Second, in the risk control stage, by considering the characteristics of large-scale construction projects such as EPC, this paper proposes the CPM scheduling approach. Then risk transference theory was used for reference to analyze the correlation among working procedures in the plan. As the delay in one procedure will cause the delay of another procedure, the risks were increased. This paper proposes to set buffer according to different processes'sensitivity to risk, so as to block the risk transference and eliminate the risk in its own process. Because the risk is distributed randomly, the buffer was set as a form of flexible time in critical paths to ensure that the critical path won't be influenced by external factors.Finally, delay interference factors identification, MC risk analysis and risk control theory were systematically applied into large-scale construction projects such as EPC and so on in this paper, and then the feasibility, scientificity and economy of the proposed methods were demonstrated.