基于HWD测试的弯沉盆面积指数法及改进

Deflection basin area index method and improvement based on HWD test

分析了目前国内民航机场刚性道面弯沉测试中的弯沉盆面积指数法,指出其存在的主要问题为反演的基顶模量的不确定性,与美国Ioannides的回归公式所反演的相对刚度半径和基顶模量相差1倍左右;此外其适用的道面板厚度范围缺乏定量指标。针对上述问题,采用有限元方法,分析了156种工况下的理论弯沉。以薄板理论弯沉值为基准,将误差在±10%范围内的数据进行了回归分析,得到修正的弯沉盆面积指数的回归系数。通过对美国联邦航空管理局（FAA）公开的HWD弯沉数据进行反算,表明采用修正后的回归公式反算的基顶模量与真实值之间的误差最大为6.9%。此外,基于薄板理论与有限元方法的计算弯沉值相对误差10%作为标准,提出弯沉盆面积指数法适用的机场刚性道面厚度范围为20~46 cm。

The deflection basin area index method in deflection tests of rigid pavement of cmTent domestie civil aviation airports is analyzed, pointing out that its main problem is the uncertainty of inversion base modulus, which has a one-time differenee from radii of relative stiffness and base modulus back calculated by the American loannides＇ regression formula. Besides, the thickness range of pavement slab applied to this method is lack of quantitative index. Ac.cording to the above problems, finite element method is used to analyze the theoretical deflection data under 156 working conditions. Based on deflection value of the thin plate theory, regression is employed to analyze test data within the error range of 10%, modified regression coeffMent of the deflection basin area parameters can be obtained. By back-calculating the public HWD deflection data of America FAA, it shows that the maximum error is 6.9% between the real value and the base modulus back calculated with the modified regression formula. In addition, based on the thin plate theory and finite element method, 10% relative errors of deflection value are chosen, puting torward that the thickness range of airport rigid pavement is 20-46 cm applied to deflection basin area parameters method.