2, artificial digging foundation pit, to keep a safe distance between operators, generally greater than 2.5 m; For multiple mechanical excavations, the distance between excavators should be greater than 10m, and the excavation should be carried out from top to bottom, layer by layer. It is forbidden to dig the toe of the slope first.
3, carefully check the surrounding environment before digging, can't work under dangerous rocks or buildings.
4, foundation pit excavation should be carried out in strict accordance with the requirements of the slope, the operation should maintain the stability of the slope, found the problem in a timely manner to strengthen the processing.
5, mechanical digging, multi-step excavation of earthwork at the same time, should check the stability of the slope. Determine the safe distance of high slope of excavator according to the regulations and checking calculation.
6, set up protective railings around the deep foundation pit, personnel should have a special ladder up and down.
Second, the quality problems that should be paid attention to
1. Overexcavation of foundation pit (ditch) or pipe trench shall not exceed the elevation of foundation pit. In case of local overbreak, the self-care method shall be approved by the design unit and shall not be handled privately.
2. Pile foundation excavation in soft soil area should prevent pile foundation displacement: when excavating foundation pit on dense pile groups, symmetrically excavate after piling is completed for a period of time; When excavating a foundation pit (groove) near dense piles, measures to prevent the displacement of pile foundation should be determined in advance.
3. The basement is unprotected: the disturbance to the foundation soil should be minimized after the foundation pit (trench) is excavated. If the foundation cannot be constructed in time, a soil layer with a thickness of 0.3m can be set aside above the elevation of the basement, and the foundation can be dug up.
4. Unreasonable construction sequence: Earthwork excavation should be carried out from low-lying areas first, and excavation should be carried out in layers and sections in turn to form a certain slope to facilitate drainage.
5. Insufficient excavation size: the excavation width at the bottom of foundation pit (trench) or pipe trench should be increased according to the construction needs in addition to the structural width. Such as the width of drainage facilities and supporting structures, should be considered before excavation.
6. The slope of foundation pit (trench) or pipe trench is not straight and uneven, and the basement is uneven: inspection should be strengthened, and it should be repaired with excavation and carefully accepted.
Legal basis: Article 11 of the Regulations on Safety Management of Dangerous Sub-projects stipulates that the special construction plan shall be examined and signed by the technical director of the construction unit and stamped with the official seal of the unit, and then implemented by the chief supervision engineer. In the subcontracting of dangerous projects, the subcontractors shall prepare a special construction plan, and the special construction plan shall be signed by the technical director of the general contractor and the technical director of the subcontractors, and stamped with the official seal of the unit.