SUBGRADE SETTLEMENT RULES OF FIRST RUNWAY OF PUDONG AIRPORT IN SHANGHAI

At present,the calculation theories for soft soil subgrade are not still perfect.The subgrade of the first runway in PUDONG AIRPORT is built on a typical soft soil area in Shanghai.Its pavement settlement has been measured for 11 years.This paper analyzes the measured pavement settlement data and finds the rules of runway subgrade settlement.The foundation settlement model is also put up.The subgrade settlement of the first runway is mainly induced by static loading.Meanwhile,the moving aircraft loading and groundwater withdraw cannot be ignored also.The calculation method and the rules of settlement induced by moving aircraft loading are put forward.The most of the subgrade settlement induced by moving aircraft loading is produced in the two or three years after the runway was commissioned.Compared with the moving aircraft loading,the groundwater withdraw can produce more subgrade settlement.In different time,the subgrade settlement constitutes differently.By the April of 2009,the subgrade settlement of the first runway was about 54cm.About 33cm of the settlementwas induced by static loading, 5cm was induced by the moving aircraft loading,and 16cm was induced by groundwater withdraw.