First, the construction method and applicable conditions of the diverticulum There are three categories: full-section construction method, layered construction method and guiding construction method. Second, the construction method and applicable conditions of the handover point 1. If the surrounding rock is hard and stable, the construction method of one lane can be used, and it can be built with the excavation, or once after excavation. The construction sequence is shown in the following diagrams I, II, III during the tunneling, and I, III, and II sequences during the support. 2. If the surrounding rock is moderately stable, the initial section of the variable section of the intersection may still be constructed once. In the larger section, the small section can be used to dig into the two lanes and build the side wall. At the same time, the column piers are digged, and then the tops of the rafts are piled up. Masonry. 3. Excavation in the soft rock stratum, the ground stress is large, if rigid support is used, it is easy to fail, and the shrinkable U-shaped steel support, or anchor spray net support, and the anchor spray net and other branches should be used. Mixed support for protection. This allows for a top-down layered construction method. If the roof is relatively broken during construction, and it is easy to fall off after the shot, the top bolt should be used to support the roof. 43 Tv Case,Generoustelevision Case,Flat Screen Television Case,Tv Protective Case Jiangsu Hengye Precision Technology Co.,Ltd , https://www.hengyejmtv.com