| The portal construction is very important in the whole tunnel construction, especially in unfavorable geologic conditions. While adopting conventional method, foundation excavation and slope cutting will be needed, which have great impact on the environment. This article starts from the issues related to tunnel portal, by studying function and form of the portal, location of the portal, construction technology and problems in portal construction procedure, under the guideline of ensuring safety, a kind of new portal construction method are introduced, which can complete portal excavation and portal construction at the same time without construction portal additionally. The method integrate portal excavation and construction process. Two trumperlike direct excavation technology are proposed based on the above idea.Under the spirit of "do not destroy is the ultimate protection", in order to achieve original purpose of maximum protection of the of rock, by researching existing tunnel construction technology, given the basic principles, construction method, technical characteristics, technical difficulties and an application of the technology in portal construction design combined with engineering practice in this paper. Using ANSYS FEM numerical simulation, studying reliability of two trumpetlike supporting structure by analyzing stress and deformation of supporting structure.This study shows that:trumpetlike direct excavation technique is a useful try and improvement for tunnel pertal construction technique, the results of the study can provide a theoretical basis for practical engineering applications.
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