摘要
为了建立公路路基压实度检测新方法,首先在深入研究静力贯入路基变形力学机理基础上,将静力贯入荷载引起的路基土体应力分为各向等压应力和轴向偏应力两部分,并考虑到路基土体变形的非线性特征,引进分级加载和地基沉降分层总和分析的思想,采用增量广义虎克定律和增量Duncan-Chang模型,建立以路基土体初始孔隙率、泊松比、粘聚力和内摩擦角等为参数的路基贯入荷载-位移分析模型;然后基于上述静力贯入位移分析模型,引进自适应遗传模拟退火优化反演分析方法,利用实测路基静力贯入荷载-位移曲线,建立基于静力贯入试验的路基压实度检测方法,并通过工程实例计算与现有方法进行对比分析。研究结果表明:该方法不仅可以检测路基压实度,还可以测定路基土体其他物理力学参数;由于静力贯入试验可移置到专用汽车以实现快速移动和检测,因此,该方法具有检测速度快和效率高的特点;该方法具有较强的合理性与可行性。
In order to set up a new detection method for compactness of highway subgrade, firstly, based on the intensive study on subgrade deformation and mechanics mechanism under static penetration, the stress of the subgrade caused by static penetration was divided into two parts： isopiestic stress and axial deviatoric stress, the nonlinear characteristics of the subgrade soil deformation was considered, the ideas of step-loading and the layer-wise summation analysis theory of foundation settlement were introduced, and the incremental generalized Hooke＇s law and the incremental Duncan-Chang constitutive model were adopted to establish the subgrade penetration load and displacement analysis model with the initial porosity ratio, poisson ratio, cohesive strength and internal friction angle as the model parameters. Secondly, on the basis of the static penetration displacement analysis model mentioned above, with the method of back analysis based on the adaptive genetic simulated-annealing algorithm recommended, and according to the subgrade static penetration load and displacement test curves, the detection method for compactness of subgrade based on static penetration was set up. The results indicate that this method can not only detect the compactness of subgrade, but also determine other physical and mechanical parameters of the subgrade soil; this method has the fast and efficient detecting characteristics because the static penetration test can be performed on a special purpose vehicle to make the moving and testing faster. The proposed method was proved to be more reasonable and feasible.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2013年第5期1-8,共8页
China Journal of Highway and Transport
基金
国家自然科学基金项目(51078137
51378198)
高等学校博士学科点专项科研基金项目(20130161110017)
