| Different types of culverts are widely used in railway and highway engineering.For culverts,the top earth pressure is of great significance to the design and structural stability of culverts.Traditional earth pressure calculation methods are either conservative or inaccurate,which is quite different from the actual ones.This study relies on the East Second Ring Expressway Project in Taiyuan City,Shanxi Province.Taking the arch culverts at K6 + 926 from Lingjingdian to Longbai section as an example,a numerical model of arch culverts and a model of pipe culverts and box culverts with similar cross-section sizes The model is established and calculated by the finite element software CANDE,and the vertical earth pressure changes of the top of the buried and trench buried culverts under different filling heights are analyzed,and then the soil arch effect is analyzed.At the same time,14 earth pressure gauges were buried in the standard section of the arch culvert,and an automatic data acquisition instrument was installed to monitor the change of the earth pressure.Finally,based on the conclusions,suggestions are made for the setting and shape selection of high-fill culverts.The main work and results of the paper are as follows:(1)Through CANDE numerical simulation calculations,three culvert models with two types of culverts under different filling heights were established.The study found that when the filling height is low,the vertical earth pressure at the top of the culvert can be approximated by the γH linearity of the overburden Calculation,the soil arch effect is not obvious;after the fill reaches a certain height,the vertical earth pressure of the top of the culvert of the buried culvert exceeds the calculated value of γH of the overlying fill,and the earth pressure concentration phenomenon appears on the top of the culvert.The vertical earth pressure of the culvert is significantly smaller than the calculated value of γH,indicating that the culvert has an earth arch effect.It is concluded that the reason for the different stress conditions is the difference in settlement between the overlying soil body and the soil bodies on both sides.(2)According to the numerical simulation calculations,the vertical earth pressure on the top of different types of culverts and culverts was studied.The minimum value of the vertical earth pressure coefficient is 0.85;for box culverts,the maximum value of the vertical earth pressure coefficient of the culvert is 1.33 when the buried culvert is buried,and the minimum value of the vertical earth pressure coefficient of the culvert is 0.78 when the trench is buried.(3)Through the numerical simulation method,the trapezoidal valley culvert was analyzed,and the model was established when the trench wall and the vertical direction formed different angles θ,and the process from the angle θ from small to large was actually the ideal trench buried type The process of transition from culvert to buried culvert.(4)Through the on-site monitoring method,the measured earth pressure and the numerically calculated earth pressure are compared and analyzed,and the error between the two does not exceed 2.7%,thus verifying the reliability of the numerical calculation results. |
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