Key points for quality inspection and acceptance of foundation pit engineering in mining area

        (1) General provisions
        1. Before the foundation pit (slot) and trench are excavated, the construction plan, environmental protection measures and monitoring plan shall be formulated according to the relevant data, and the construction may be carried out after approval.
        2. Quality requirements for construction and drainage:
        Before the construction of the earthwork, the design of the drainage and the system inspection and commissioning shall be completed. The construction quality inspection of the drainage and drainage work includes the slope of the drainage ditch, the verticality and spacing of the well pipe (point), and the insertion depth.
        When precipitation occurs outside the foundation pit, there is an estimate of the precipitation range and monitoring of important buildings around it.
        3. Inspection and deformation monitoring of foundation pits:
        After the foundation pit (groove) and trench are excavated to the design elevation, the bottom of the pit shall be protected. After the experience slot is qualified, the cushion construction may be carried out. For extra large foundation pits, it is advisable to divide the blocks into the design elevation and divide the blocks into blocks.
        Foundation pit (slot), pipe trench earthwork acceptance must ensure the safety of the support structure and the surrounding environment. When the design has indicators, it should meet the design regulations. When designing the indicators, the maximum displacement of the table lG420073 should be taken as the standard.
        Note, 1. One of the following conditions is the first-level foundation pit z
        (1) an important project or supporting structure as part of the main structure;
        (2) The excavation depth is greater than 10m;
        (3) Foundation pits within the depth of excavation from adjacent buildings and important facilities;
        (4) Within the scope of the foundation pit, there are historical foundations and other foundation pits that need to be strictly protected.
        2. The three-level foundation pit is a foundation pit with an excavation depth of less than 7m and no special requirements in the surrounding environment.
3. Foundation pits other than Grades 1 and 3 are secondary pits.
        4. These requirements should also be met when there are special requirements for existing facilities around.
        (2) Pile wall support, steel or concrete support system
        1. The piles that constitute the support of various types of pile walls shall meet the quality requirements of the corresponding piles. Concrete sheet piles should be inspected for the length of the pile and the bending of the sheet pile to meet the allowable deviation requirements.
        2. Support construction should strictly control the order and time relationship of excavation, as well as the location of support, the depth of excavation per layer, and the pre-addition force. Deviation of the plane and horizontal position of the steel or concrete support, the pre-supporting force deviation shall comply with the regulations.
        (3) Anchor rod and soil nail wall support engineering
        1. During the construction process, the diameter, depth and angle of the borehole, the position of the bolt or soil nail and the insertion length, stress, grouting ratio, pressure and grouting amount, thickness and strength of the spray layer shall be checked. Among them, the anchor soil nail length and the bolt locking force are the main control items for inspection.
        2. After each section of construction is completed, the displacement of the slope top or slope surface, the settlement of the slope top and the surrounding environment shall be checked. If there is any abnormality, measures shall be taken in time to resume construction after normal operation.
        (4) Underground continuous wall
        1. During construction, the verticality of the trough, the thickness of the silt at the bottom of the trough, the specific gravity of the mud, the size of the steel cage, the position of the pouring pipe, the rising speed of the concrete, the elevation of the pouring surface, the cleaning degree of the connecting surface of the underground wall, and the commodity? The time and speed of the drop, the lock tube or the joint box.
        2. After the groove is finished, check the groove width, depth and inclination. The number of inspections should be in accordance with the regulations. Each 50m3 concrete wall shall have a set of test pieces, and each groove section shall be no less than one set; the earthwork may be excavated after the strength meets the requirements. The strength of the wall and its verticality are the main control items for the inspection of the continuous wall.

Seat Cover Cushion

Carseat Cushion,Seat Cover Cushion,Heated Seat Covers,Heated Car Seat Cover

Ningbo Yonghai Auto Products Co., Ltd. , https://www.yonghai-manufacturer.com

Posted on