When cracks or local subsidence are found in the trench slope during trench construction.

When cracks or local subsidence are found in the groove and the slope of the groove during the groove construction (a). ?

A, immediately evacuate personnel to a safe place, and report to the relevant departments in time. No adventure. ?

B, first report to the relevant departments, workers on standby.

C, immediately evacuate personnel to a safe place, to deal with hidden dangers. ?

D, let workers deal with hidden dangers themselves.

In engineering, when the width of the trough bottom is less than 3m and the length of the trough bottom is more than 3 times the width, it shall be calculated as a trough. The length of earthwork for foundation trench excavation shall be calculated according to the length of the center line. If the trench earthwork is connected with an independent foundation pit or earthwork, its length shall be reduced by the bottom width of the independent foundation pit or earthwork.

Foundation pit refers to the space below the ground excavated for the foundation, basement and pipeline of buildings (including structures). The temporary pit for building foundation excavation is called foundation pit. Foundation pit is a temporary project, and its function is to provide a space for foundation masonry work in accordance with the designated position of design.

Before digging ditches, you should know the soil and groundwater. Find out the location, depth and direction of underground pipelines, cables or toxic gases, and set up signs and guardrails. Before the implementation of the project, the construction personnel must make a detailed disclosure to the operators. Its contents include: underground facilities, dangers, safety measures, operation methods and safety precautions in construction.

Guardrails and warning signs should be set up when digging near the site passage, and red warning lights should be set up at night. Vehicles and equipment shall not be piled up or parked within 0.8m of the groove edge. When excavating, it should be carried out from top to bottom in turn. It is forbidden to dig holes. Mechanical excavation and earthwork should be commanded by special personnel.