刚性道面弯沉盆重心距离法及回归模型

提出一种刚性道面弯沉盆重心距离法(MAREA)及回归模型,在系统建模和分析传统弯沉盆面积指数法(AREA)的基础上,从综合利用各个测点弯沉值信息的角度,以弯沉盆重心距离指标替代弯沉盆面积指数,推算相对刚度半径;并以实测弯沉盆误差最小为准则,计算板下地基反应模量,从理论上解决结构参数反演的多解性.在典型的刚性道面结构形式下,分析改进方法采用最佳的传感器数量以及可靠性.结果表明,改进后的方法可较大提升反演结果的可靠性,能有效处理测量误差.基于落锤式弯沉仪(FWD)实测数据的模型验证结果也表明,该改进方法相对于其他方法能减少拟合误差.采用五次多项式建立了无偏的回归模型,大大提高了反演的效率.

Improved AREA Back-Calculation Method for Rigid Pavement and Its Regression Model

This paper presented an improved back calculation method for rigid pavement and its regression model. Based on the modeling and a thorough analysis of the traditional AREA, the index of barcentric horizontal distance was proposed to replace the AREA index, and then the radius of relative stiffness was calculated by using each sensor deflection information. The modulus of subgrade reaction was calculated to minimize the error of filed test deflection basin. With the above two features, the improved method can theoretically solve the problem of multiple back calculation solutions of the traditional AREA. Taking the typical structural style of rigid pavement as a study case, the best number of sensors and the reliability of improved method were comprehensively analyzed. The numerical analysis results demonstrate that the improved method can significantly improve the reliability of back calculation and effectively handle the measured error. The field test validation results using the FWD deflection basin has also proved that compared with other methods, the improved method has a stronger ability to decrease the fitting error of measured deflection. For the improved method, five times polynomial was adopted to establish the unbiased regression model, which greatly improve the efficiency of the inversion.