摘要
为查明武汉湖相沉积淤泥的蠕变特性,开展固结不排水的三轴剪切蠕变试验。结果表明,武汉淤泥具有显著的蠕变特征,且具有非线性蠕变特性。低剪应力下,蠕变变形小;高剪应力下,出现瞬时变形、非稳定变形与稳定变形,剪应力越大,非稳定变形越大;较高剪应力下,发生快速破坏。孔压变化与蠕变变形规律基本一致。Burgers模型可较好地预测武汉淤泥的不排水剪切蠕变变形,该模型具有参数少、参数物理意义明确的特点。研究还表明,增大固结压力可以减弱蠕变变形,可采用超载预压方式提高土体的固结度,进而可有效减小因蠕变引起的工后沉降。
In order to study the creep characteristics of lacustrine silt in Wuhan,consolidated undrained triaxial shear creep test was carried out.The results that show creep characteristics of Wuhan silt are significant and nonlinear.Under low shear stress,creep deformation are little;under high shear stress,instantaneous deformation and stability deformation and non-steady deformation is appeared,and the greater the shear stress,the greater the non-steady deformation;under high shear stress,rapidly destruction is occurred.Pore pressure change is consistent with the law of creep deformation.Furthermore,Burgers model has fewer parameters,its parameters are defining physical meanings,and can better predict undrained shear creep deformation of Wuhan silt.The study also shows that,increasing consolidation pressure can weaken the creep deformation,and preloading consolidation of the soil can be effectively reduced post-construction settlement due to creep.
出处
《施工技术》
CAS
北大核心
2014年第S1期89-92,共4页
Construction Technology
