Study On High-Grade Highway Construction Cost Estimate Model Based On Analysis Of Influence Factors

With the great development of highway construction in China, the scale of highwaynetwork expands and the proportion of high-grade highways gradually increases. At the sametime, the development of highway faces an enormous challenge: high-grade highways’construction cost increase rapidly. In order to find the main influence factors and made costestimate model based on them, in this study, some multiple linear regression models will bemade based on a large number of research data.This research is on the basis of the influence factors of highway construction cost, andclassifies them into macro and micro factors. Moreover, the micro–factors are divided intothree catalogues, which are the price factor of human work, building materials andconstruction machinery, engineering factor and land acquisition factor. And such classificationis resulted from statistical analysis on the research data of all factors, which are extractedfrom the practical engineering experience. Multiple linear regression models are used,dependent variable is each driveway kilometers unit cost and independent variables areinfluence factors of instruction cost, so that the macro factors cost estimation model and themicro factors cost estimation of each level road model are constructed. Therefore, thecomparisons of3kinds of factors above mentioned are made according to the application ofthe models and PCA (principal compenent analysis).The study presents that all the models constructed have reached the ideal goodness-of-fit.To be specific, the data R2of first-class and secondary road construction cost estimationmodels are both around0.8, which means the models have the capacity to make the relativelyaccurate estimation of construction cost. The study results demonstrate that the level ofconstruction cost is more sensitive to time, technical grade,GDP per Capita included in themacro factors; Free way’s construction cost is more sensitive to the price of petroleum pitch,viaduct length ratio and average cost per lane kilometer of land requisitioned; the first-classhighway’s construction cost is more sensitive to price of Steel，bridge and tunnel length ratioand and average cost per lane kilometer of land requisitioned; for secondary roads, includingthe same sensitive elements as those of class one highway, the sensitiveness also appears inprice of some kinds of local material, machines and fill–excavation engineering. As the result of importance comparison about the three kinds of influence factors, price factor takes a moreimportant position in the influence of freeway construction cost levels, meanwhile,engineering factor is an significant factor of both first-class highway and secondary roadconstruction cost.