# Reliability Analysis of the Main Pier during the Construction Period of HLCR Bridges
###### Abstract
The reliability level was comprehensively selected according to the exposure time of the temporary load, construction cost of temporary works and other factors. [PERSON] et al. [7] took the Jingzhou Yangtze River Highway Bridge as the research object, and carried out a detailed calculation and analysis of its overall stability and parameter sensitivity in the most unstable state during the construction phase. The research results showed that the self-weight error of the superstructure on both sides of the pier during cantilever construction was the main factor affecting the overturning stability of the bridge during the construction period, while the wind load had little effect on the stability reliability, which provided a subsequent bridge overturning resistance research reference. [PERSON] [8] calculated the reliability of two failure modes when the cantilever cast-in-place method was used to construct up to the last section of the girder block, and performed a parametric sensitivity analysis. The results of the study provide a reference for managing the construction phase of the structure. [PERSON] et al. [9] used ABAQUS software to establish a three-dimensional finite element model for cantilever balanced construction of segmental bridges, and tracked the structural response during construction and the whole service life. Significant time-dependent effects on bridge deflection and internal forces and stress redistribution were observed. Based on the estimated distribution of the dead load, live load and wind load, [PERSON] et al. [10] conducted reliability evaluation research on the main truss members and the whole structural system of the longest along-span truss bridge in the United States. The results show that the response to temperature significantly impacts the reliability of the whole system. [PERSON] (2011) analyzed the factors affecting the alignment of the main girders during the bridge construction phase of the Zhenyuan Canal Bridge, and proposed that the deflection change of the girder end should be controlled at each step of the bridge construction to obtain a reasonable alignment of the completed bridge. After analyzing the overturning stability of a three-span continuous girder bridge under the most unfavorable conditions in the construction phase, [PERSON] et al. [PERSON] et al. (2012) identified the parameters with the greatest influence on the reliability index and determined their value ranges, thus improving the safety of the solid structure during construction. By considering the actual bearing capacity and actual situation of the bridge, [PERSON] et al. [PERSON] et al. (2013) proposed a complex existing bridge evaluation method based on the defect point method. Using the developed method, the priority of a bridge repair can be determined. [PERSON] (2014) analyzed and studied the stability reliability of an HLCR bridge when the cantilever was constructed to the longest state, and concluded that the elastic modulus and self-weight of concrete had a large effect on the stability reliability of the bridge, while the wind load had little effect. At present, there are many methods to calculate the structural reliability index; suitable analysis methods can be selected for the characteristics of different engineering structures, subject to the continuous improvement of our knowledge by domestic and foreign research scholars ([PERSON] et al., 2015). The JC method, MC method, and response surface method are the most commonly used and widely studied reliability calculation methods at present. The earliest international method to calculate reliability was the centroid method proposed by [PERSON] (2016) in the early stage of structural reliability research, which is also the simplest method. The basic idea is to first make a Taylor series expansion of the nonlinear function at the centroid of the mean of the random variable and retain it up to the primary term, and then approximate the mean and standard deviation of the function ([PERSON] et al., 2015).