Research On Key Parameters And Pay Factor For Cement Concrete Pavements In End-result Specifications

An important part of End-result specifications is that the quality of pavements has direct relation with the fees. Through studying on the key parameters and pay factor of cement concrete pavements, this article seeks to determine the key parameters and their weights which would be used to establish a complete set of pay factor calculation system, so as to improve the charge of"the high quality and favorable price"on cement concrete pavement products basically.This thesis started from the statistical base of the studying on key parameters and pay factor of cement concrete pavements. And the probability distribution types of the parameters were determined through the statistical analysis of a large number of cement concrete pavement parameter samples. In addition, the stratified random sampling method was used to ensure the representative of sampling.Then, based on reliability theory in pavement mechanical analysis, a new technology which could determine the key parameters and their weights of cement concrete pavements was put forward in this thesis. The average and variation coefficient of parameters which include flexural strength and slab thickness of cement concrete pavements were obtained through conducting statistical analysis on the testing data collected in some actual pavement projects. Conducting the reliability analysis on typical cement concrete pavements, the effects of the average and range of variation coefficient of key parameters on reliability of typical pavement structures were confirmed. The key parameters and their weights were determined on the basis of sensitivity of parameter variation to the reliability of cement concrete pavements. As the results showed, the key parameters of cement concrete pavements were flexural strength and slab thickness. The relative weight of flexural strength to slab thickness of cement concrete pavements can be determined logically based on reliability analysis of pavements. Because of that the key parameters can not respond the quality level of the pavements completely, this thesis presented that the pavement performance would be evaluated with the clustering method of albino grey function. It's chief train of thought is that establish an albino grey function model with the pavement condition index, smoothness, and texture depth as its main evaluating parameters, and then obtain a clustering value of grey which would be an evaluation parameter of pavement performance by clustering analysis, importantly, this clustering value of grey is a payment adjusted parameter as well.At last, based on calculation of PWL for key parameters of cement concrete pavements, the computational method of pay factor for single key parameter was determined. Taking the key parameters'weights in consideration, and making the clustering value of grey which responded the pavement performance as the adjusted index of payment, the final synthesis pay factor was obtained. And the final conclusion is that the out-of-pocket cost that the owner must pay to the Contractor is the multiplication of synthesis pay factor and primitive expense of product.