Construction method of loess tunnel wall-attached portal entering

The invention discloses a construction method of loess tunnel wall-attached portal entering. The construction method comprises the steps that firstly, a full-annular cover arch is constructed througha three-step method; secondly, a soil mass within the range of an upper-step cover arch is excavated; thirdly, a first upper-step arch frame is arranged at the boundary of the upper-step cover arch and the terrain; fourthly, upper-step foot-locking anchor pipes are arranged; fifthly, advanced guide pipes are arranged at the first upper-step arch frame to form a shed frame structure; sixthly, formworks are overhead supported and arranged on the outer side of a mountain; seventhly, concrete is sprayed to manufacture the upper-step cover arch located on the outer side of the mountain; eighthly, excavation is conducted at the first upper-step arch frame in the direction of the inner side of the mountain, the upper-step arch frame is erected, and concrete is sprayed to manufacture the upper-step cover arch located on t