Human Reliability Analysis Of Highway Prestressed Concrete Beam During Construction Process And Its Effect On Structual Reliability

It is always the most crucial responsibility for engineers to ensure the infrastructure’s safety and reliability. Recently, the level of elements such as material strength, techniques and machine-manipulating that influence construction’s reliability has become great developed. Though, the academic research about human element which is another source of uncertainty towards structure reliability still remains early-stage. Study shows that, almost all the construction accident and failure cases can trace their root reason back to human errors. Since human error event is an aggregation of several cases with high randomness and the human error’s influence to structural reliability is also uncertain, for describing the mechanism of the human error’s influence, scholars brought up the concept of human reliability and human error probability. This paper use the Cognitive Reliability and Error Analysis Method (CREAM) to analysis and evaluate the human reliability and human failure probability of the whole precasting process. The main contents of this paper are as follows:(1) Focusing on the specific structural constructing mission in the realm of civil engineering, this paper established a new human reliability analysis method that combine both CREAM and the Technique for Human Error Rate Prediction(THERP) theories.(2) This paper designed and implemented a full-member questionnaire about the working site’s context situation, results of which could be used to allocate and evaluate the Common Performance Conditions (CPC) defined by CREAM as a comprehensive measurement about working context’s influence about reliability.(3) Using the human error possibility forecasting method from CREAM, this paper tried to build a cognitive demand profile which includes every working steps’cognitive activity property, cognitive function property, cognitive failure types and cognitive failure possibility. Still, the context condition’s effect towards the failure possibility is also considered by adjusting the possibilities with CPC levels.(4) By using the event tree model from THERP, one of the human reliability research methods, this paper compiled all the Cognitive Failure Possibility (CFP) into one result, during the process of which, series-wound logical relationship among and relativity between the steps is considered. What’s more, several control measures are mentioned specifically aim at the human reliability analysis’s process and outcomes to decrease the CFP.(5) This paper also managed to establish the influencing relationship about CFP and structural reliability. To be specific, based on the real case, it deducted the changes in relationship between design reliability and CFP aiming at ensuring real structural reliability equals to the target reliability.