Emergency rescue measures for collapse accidents in tunnel projects

In case of landslides, in addition to promptly rescuing construction workers, the undamaged section must be quickly reinforced to prevent the collapse of landslides and prepare for the collapse. At the same time, find out the situation of landslides and investigate the scope of landslides and the status of landslides after landslides. Analyze the causes of the collapse and its nature, intermittent rules, and site conditions of landslides. Dealing with landslides should be based on the principles of "small plugging, large collapsed wear," and "treating water before it collapses." Small collapse in the collapse interval, seize the time to deal with. It is necessary to support the clearing afterwards, that is, to clean up the landslides afterwards and change the pillars for cleanliness. If the collapse is high, multi-row support can be adopted, and the top layer and cavern wall should be tight. When conditions are suitable, shotcrete can also be used and temporary collapse can be dealt with. When the landslide cannot support the caverns and the size cannot be ascertained, it is not allowed to remove slag to prevent it from collapsing with the cleanliness and rapidly expand the landslide area. Therefore, it is necessary to go through the collapse and use the construction sequence of "protecting and digging first". After the collapsed end supports and linings are reinforced, they are usually constructed by inserting panels. The inserts can be seen as soft and hard crushed stone slag, and can be made of wood, steel fiber or rails, etc. The slag can be cleaned and promptly erected under the protection of the insert. Support, expansion, also need to enter the flap horizontally, with the expansion of support. The part that passes through the collapsing body should pass through the collapsing body from the vault and the upper section and then proceed downwards. The roof collapse is an extreme situation for big caves. Drainage trenches are dug around to prevent surface water from collapsing into pits, and clay cracks are used to fill in the cracks around the ground. Acupuncture and mouth businesses should use rain canopies to prevent rainwater from pouring into the caverns. When dealing with landslides, prevention and drainage should be strengthened, and appropriate measures should be taken to draw away the groundwater from the landslide. When the big landslides are used to pay for work, in order to speed up the construction progress, measures can be taken to bypass the collapse of the guide pits, so that the collapse can be dealt with simultaneously with the construction of the main tunnel. However, care should be taken when choosing the turnaround guide pits. Collapse occurs again in the diversion pit, or the cavern is expanded into the diversion pit. The surrounding rock in the collapsed section is extremely unstable and the surrounding rock pressure is increased. Therefore, the lining structure must be strengthened accordingly, and reinforcement measures should be taken for the surrounding rock, such as protecting the arches with mortar and chipping stone outside the lining, pressing the cement slurry in the landslide, etc. And do a drainage project to avoid future problems.