减荷措施下高填涵洞竖向土压力计算  

Computing of the Vertical Earth Pressure on High-Fill Culverts under Load Reduction Measures

作　　者：程振威 李又云[2] 王传波 Cheng Zhenwei;Li Youyun;Wang Chuanbo(Power China GuiYang Engineering Corporation Limited,Guiyang 550081,P.R.China;School of Highway,Changan University,Xian 710064,P.R.China)

机构地区：[1]中国电建集团贵阳勘测设计研究院有限公司,贵阳550081 [2]长安大学公路学院,西安710064

出　　处：《地下空间与工程学报》2024年第6期1790-1797,共8页Chinese Journal of Underground Space and Engineering

摘　　要：为探究高填方减荷涵洞的受力状况,基于小主应力拱概念,并结合Marston理论,推导出了减荷条件下盖板涵竖向土压力的计算公式,公式综合考虑了填料物理力学指标、涵洞结构尺寸、填土高度等多种因素。研究发现:减荷条件下,土拱效应的产生使涵洞结构上方竖向应力转移至结构外侧土体中,从而减小了洞顶受力,土拱效应对外侧土体应力影响范围约为0.5倍结构宽度,沿结构宽度方向,结构竖向土压力均衡分布;洞顶填土高度小于结构高度时,土拱效应不明显;大于结构高度时,减荷措施效果显著,且填土高度越大,减荷效果越理想,涵洞竖向土压力随填土高度的增加近似线性增长,但增速较缓;通过与现场实测值、数值模拟结果对比发现,公式具有一定准确性、适用性。In order to explore the stress state of high-fill culvert under load reduction,the expression of vertical earth pressure on slab culverts under load reduction condition was derived based on the conception of minor principal stress arch and combined with the Marston theory.Physical and mechanical properties of filling,culvert sizes,height of the fill have been considered in the formula.The results show:the vertical stress above the culvert structure is transferred to the soil outside the structure by soil arching effect under load reduction condition,which reduces culvert pressures.The influence range of soil arching effect on the stress in the external soil column is about 0.5 times of the structure width.Vertical earth pressure of structure is distributed evenly along the structure width direction.The soil arching effect is unconspicuous when the filling height on the top of tunnel is less than structure height.When the filling height on the top of tunnel is greater than structure height,the effect of load reduction measures is obvious.And the higher the filling height is,the more significant the load reduction effect is.The vertical earth pressure on culvert increased approximately linearly with the increment of fill height,but the growth rate is slowly.The formula shows certain accuracy and applicability by comparison with field measured values and numerical simulations.

关 键 词：小主应力拱 减荷 高填方盖板涵 竖向土压力 数值模拟 

分 类 号：TU432[建筑科学—岩土工程]