交通荷载对场道地基工后沉降的影响分析

基于软土地区民航枢纽机场跑道飞机荷载特点,结合上海浦东国际机场第一跑道6年多的沉降观测数据,定量分析交通荷载对场道地基工后沉降的影响.采用对数曲线模型描述场道地基在恒载条件下的工后沉降规律,并用跑道竣工后尚未通航期间的沉降数据标定模型参数,跑道运营期间的恒载沉降与实测沉降的差值可视为交通荷载作用下的场道地基工后沉降.分析表明,在该跑道通航第5年,交通荷载作用下的场道地基工后沉降占工后总沉降量的比例达 31%,且这一比例最终将超过50%.这说明今后应在场道软土地基设计中充分考虑交通荷载对工后沉降的影响.

The Effect Analysis of Traffic Loads on Post Construction Settlement of Subgrade

Based on the characteristics of aircraft loads and more than 6 years measured settlement data in Pud- ong international airport,the validation of importance of considering the moving aircraft loads in settlement prediction is proved.This paper adopted a logarithm model to fit the measured settlement data before the runway was opened to aircraft traffic and took the difference between dead loads induced settlement(S_s)and measured total settlement(S_m) as settlement induced by moving aircraft loads(S_d).From the calculation results,S_d was 31% of S_m in 5 years on the average and the proportion will increase to 50% finally.The research results showed the traitic loads should be taken into account in soft foundation design of runway.