路基刚度对冲击碾压混凝土路面动力破碎效果的影响  

Influence of Subgrade Modulus on Dynamical Cracking Effect of Existing Impact-Compacted Concrete Pavement

作　　者：胡昌斌[1] 阙云[1] 王国业[2] 

机构地区：[1]福州大学土木工程学院,福建福州350002 [2]沈阳建筑大学科技产业处,辽宁沈阳110168

出　　处：《沈阳建筑大学学报（自然科学版）》2009年第4期670-676,共7页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学青年基金项目(50808086);福建省高等学校新世纪优秀人才计划(TW2006-27)

摘　　要：目的揭示路基刚度对冲击碾压混凝土路面动力破碎效果的影响规律.方法基于动力弹塑性有限元分析方法,建立了冲击碾压改建三维动力有限元分析模型,针对不同路基刚度对四楞冲击压路机冲击碾压混凝土路面动力破碎效果的影响进行了系统研究.结果随着路基刚度的增大,板的瞬时竖直变形最大值减小;纵向拉应力有减小的趋势,而相应的纵向压应力逐渐增大;横向拉应力变化也有相同的趋势;路基刚度较小时,路面板横向的拉应力大于纵向的拉应力,而随着路基刚度的增大,纵向拉应力增大幅度大于横向拉应力的增长幅度,最后纵向拉应力大于横向拉应力.随着路基刚度的增大,路面板底的纵横塑性应变最大值相应减小,纵向塑性区分布范围逐渐增大并向板中集中,而横向塑性区分布范围逐渐减小,且由原来的纵向分布变为横向分布.结论路基刚度对于冲击碾压改建破碎路面的效果和性状有较大影响,路基刚度越大路面越难以破碎,断裂方向由纵向逐渐转为横向,针对不同刚度路基建议根据破碎效果选择对应的施工路线.In order to explain the influence of subgrade modulus on dynamical cracking effect of existing impact-compacted concrete pavement, the influence of different subgrade modulus on cracking effect under impact load of quadrilateral impact roller was studied based on three dimensional elastic-plastic dynamic FEM. The results indicate that the maximum value of instantaneous vertical deformation of slab decreases with the increase of subgrade modulus;longitudinal flexural-tensile stress and transverse flexual-tensile stress show gradual lowering tendency, and compressive stress shows a go-up tendency. The transverse flexual-tensile stress is greater than longitudinal flexural-tensile stress when subgrade modulus is relatively small. With the increase of subgrade modulus, the amplitude increase of transverse flexual-tensile stress is greater than that of longitudinal flexual-tensile stress, and longitudinal flexual-tensile stress is greater than transverse flexural-tensile stress in final. The maximum values of longitudinal plastic strain and transverse plastic strain at bottom of slab decrease with the increase of subgrade modulus. The distribution range of longitudinal plastic zone is gradually enlarged and concentrated to central areas of slab, and the distribution range of transverse plastic zone is decreased and longitudinal distribution is changed to transverse distribution. It is difficult to be cracked when subgrade modulus is larger, and the fracture direction of slab is changed from longitudinal direction to transverse direction. So, it is reasonable to choose the constructing scheme according to different road conditions.

关 键 词：冲击碾压 水泥混凝土路面 路基刚度 弹塑性动力有限元 破碎效果 

分 类 号：U416.216[交通运输工程—道路与铁道工程]