围垦区内湿度场变化对道路横向应力的影响

Effect of humidity variation on transverse stress of road in reclaimed area

在沿海围垦区内,由于近海处和远海处的湿度不一,随着时间的推移,湿度场变化将导致土体失水收缩不均,道路路基由于约束的存在,土基内部将产生不均匀的拉应力和拉应变,进而导致道路开裂破坏,使用寿命减少。基于湿度应力场与温度应力场的相似性,采用ABAQUS有限元分别计算在变湿度场下土基的横向变形,并将其耦合到路基之中从而计算出路基的横向拉应力和拉应变。结果表明:在经过5年的干湿循环后,路基路面结构在变湿度应力场中产生较大的横向附加应力,并且在各结构层的横向附加最大拉应力接近各结构层材料的容许应力强度。

In coastal reclamation district,the humidity varies between offshore and inland.With passage of time,the uneven shrinkage is caused by the change of humidity.Uneven tensile stress and strain will be generated in the soil foundation with the existence of constraints,which further leading to cracking and shortage of road service life.Based on the similarity of humidity stress field and temperature stress field,the ABAQUS finite element software was adopted to calculate the transverse deformation of earth foundation under variable humidity,and then the transverse tensile stress and strain of the subgrade were calculated by coupling transverse deformation to the subgrade.The results show that after 5 years of dry-wetting cycle,large lateral additional stress has been produced in subgrade and pavement under the variable humidity stress field,and the maximum lateral additional tensile stress in each structural layer is close to the allowable stress intensity of each structural layer material.