Study On Mechanical Behavior Of Unsymmetrical Loaded Double-arch Tunnel

The thesis is based on the comprehensive analysis of current double-arch tunnel research results and rely on Dongkoutang double-arch tunnel and Linjiaxi double-arch tunnel in Shaohuai (Shaoyang-Huaihua) highway. Regard solving mechanical behavior of double-arch tunnel under the landform unsymmetrical loaded and construction unsymmetrical loaded condition as the starting point. Analyse double-arch tunnel with different construction method by through using the method of numerical analyse, combine monitoring measurement result, take the stress and distortion characteristics of double-arch tunnel as study problems.Analyse double-arch tunnel with different construction method by through using the method of numerical analyse, Have drawn the mechanics law and distortion law of surrounding rock, support structure and mid-wall under the function of the landform unsymmetrical loaded and construction unsymmetrical loaded condition. Study several problems such as the changing laws that distortion of dual-rach tunnel follows parameters of landform unsymmetrical loaded, the changing laws of the effect that landform unsymmetrical loaded function on tunnel follows depth of embedding and function of secondary linings in project;combine monitoring measurement result, several results are proved by using the method of numerical analyse, such as distortion characteristics of double-arch, the situation of secondary linings and stress characteristic of mid-wall. The result show under the the landform unsymmetrical loaded and construction unsymmetrical loaded condition, the distortion of double-arch is asymmetrical, mid-wall still bearing certain moment after construction, the left tunnel and the right tunnel will interact each other in construction. These results should be of guiding significance to design and construct double-arch tunnel engineering.