Research On Railway Construction Schedule Compression Algorithm Based On LSM

In recent years,railway construction has always been a key area of infrastructure construction in China.In the construction of railway engineering,the complexity of the project itself,the uncertainty of environmental factors,the difference of construction process,the rationality of construction organization design and many other factors often have a major impact on the construction schedule,resulting in delays in the construction period at a specific stage.In order to ensure the completion of the entire project on time,it is necessary to speed up the construction of the project,compress the construction schedule of the post-construction tasks,and compress the construction schedule to become the main problem that the contractor needs to solve in order to adjust the progress of the project.This paper focuses on the selecting of active segments in the schedule compression,and carried out the following research work:First,starting from the linear characteristics of railway engineering,the linear scheduling method(LSM)is applied to railway construction schedule management,and the construction schedule is visualized using a linear scheduling diagram.Secondly,the analytic hierarchy process(AHP)and fuzzy evaluation methods are used to analyze the influencing factors of construction activity acceleration,and the quantitative analysis of the contractor's process of selecting for construction period compression construction activities from subjective perspective is carried out.Thirdly,the LSM-based railway construction period compression algorithm is studied.The algorithm is divided into four steps:the first step is to select the accelerated active segment by the graphical feature;the second step is to determine the priority according to the absolute value of the area moment difference,the acceleration cost of the active segment,and the subjective screening result of the contractor;The weight assignment produces a joint priority;the fourth step is to compress the duration of the highest priority active segment and iteratively solve until the required duration is reached.Finally,a case study was conducted with the Wuzhun Railway as an example.According to the sub grade engineering of Wuzhun Railway,each compressed active section is selected according to the railway construction period compression algorithm,and the total cost of the required construction period is iteratively solved,and compared with the results of the traditional algorithm,the effectiveness of the algorithm is verified.