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本文对宾夕法尼亚州运输研究所试验路面的性能进行了评定。这些路面包含五种不间的基层类型:沥青混凝土,沥青稳定粒料,水泥稳定粒料,石灰—火山灰稳定粒料和碎石。大部分路面经受了相当于40年使用期,约240万18000磅当量轴载的作用。分析的数据为路面耐用性指数和三种破坏现象—不平整度、车辙和裂纹。同时应用使用性能资料对一些现有的路面使用性能模型进行了评价。这些使用性能资料表明,耐用性指数随当量轴载(EAL)的增加而降低的趋势服从于由美国各州公路工作者协会(AASHO)道路试验建立的指数函数关系。在被评定的性能模型—AASHO模型、公路研究委员会(HRB)的修正模型以及Painter模型—中,AASHO模型看来预测的结果最好,虽然它过高地预测了路面的使用寿命。采用曲线拟合和回归分析方法建立了路面性能指数及结构数的相关方程。这些方程可用来预测耐用性的损失率以及达到某一现有耐用性指数下降值所要求的路面寿命。同时建立了结构数与路面损坏和临界路面反应与使用寿命之间的相关方程式,这些方程式可用来由结构数预测不同程度的路面损坏,也可用来由临界的路面反应预测路面的使用寿命。按照这些分析结果,路基＄面的最大压应变似乎比最大表面弯沉在预测路面使用寿命上是一个更好的因素。
This article assesses the performance of the Pennsylvania Institute of Transportation test pavement. These pavements include five basic types of grassroots: asphalt concrete, asphalt stabilized pellets, cement stabilized pellets, lime-pozzolanic stabilized pellets and gravel. Most pavements have been subjected to an equivalent axle loading of 2.4 million 18,000 pounds equivalent over a 40-year service life. The data analyzed were pavement durability index and three types of damage - roughness, rutting and cracking. At the same time, some existing pavement performance models were evaluated using performance data. These performance data indicate that the trend toward a decrease in durability index with equivalent EAL is subject to the exponential function established by the AASHO Road Test of the States of the United States. The AASHO model appears to yield the best results in the assessed performance model, the AHOHO model, the revised HRB model, and the Painter model, although it over-predicts the useful life of the pavement. The correlation equations of pavement performance index and structure number were established by curve fitting and regression analysis. These equations can be used to predict the loss rate of durability and the life of the road surface required to achieve a certain degradation of existing durability index. At the same time, the correlation equations between structure number, pavement damage and critical pavement response and service life are established. These equations can be used to predict different degrees of pavement damage by the number of structures and can also be used to predict the service life of pavement by the critical pavement reaction. Based on these analyzes, the maximum compressive strain on the subgrade surface seems to be a better factor than the maximum surface deflection in predicting the useful life of the pavement.