Study on Criterion of Differential Settlement in Subgrade Widening Project of an Expressway

摘要

Criterion of differential settlement in subgrade is useful for keeping road in a good serving condition.The theory of traditional materials strength and their technologic economy are applied to analyze the additional bend stress of the pavement structure,the equivalent beam of elastic foundation and influence on the pavement structure of an uneven settlement.The allowable settling ratio of pavement index(Δi)is got and is used to appraise the uneven settlement standard value in subgrade.The allowable settling ratio of pavement index is applied in an certain widening expressway project and Δi0.36% is attained by the analyzing,calculating and adding a certain safe coefficient.This value was put into practice and is effective during the past two years.