高填方路基钢波纹管涵洞土拱效应分析

The Analysis of High-filled Steel Corrugated Pipe Culvert Soil Arching Effect

土拱是土体不均匀变形过程中逐渐形成的荷载传递形式,对岩土工程中应力场和位移场的变化和发展过程产生着重要影响。针对目前关于土拱效应理论的研究现状,通过现场试验和室内模拟分析对高填方钢波纹管涵洞管顶土拱效应进行了研究。结果表明:高填方涵顶土压力不是成σ=γH分布,而是成非线性分布;随着填土高度的增加,涵顶土压力增加幅度逐渐减小。当涵顶填土达到一定高度以后,在涵洞上方将产生拱效应,但由于高填方涵洞上方路基填料是不同于岩石的散粒体,高填方涵洞上方的拱效应具有不稳定的特点,使上部填土压力在填土高度增加过程中仍能部分地传递到涵顶上,使涵顶上的土压力小于理论土压力并随填土高度成非线性规律变化。

The soil arching is a load transfer form,which gradually formed in the inhomogeneous deformation process of soil; in geotechnical engineering,it has an important impact on the transformation and development process of the stress field and displacement field. According to the current research status about soil arching effect theory,analysis the soil arching effect on the top of the high-fill steel corrugated pipe culvert through the field test and laboratory simulation. The results show that the top soil pressure of the high-filled culvert is not distributed as σ = γH,but the nonlinear distribution; with the increasing of filling height,the increasing amplitude of the culvert top soil pressure gradually decreases. When the fills on the culvert reaches a certain height,the arching effect will occur at the top of the culvert. Because the fills on the culvert are different from the rock,the arch action above the high fill culvert has the characteristics of unstability and the earth pressure can partly transfer to the top of culvert,which makes the earth pressures on the top of culvert less than the theory of soil pressure and increase nonlinearly.