Safety technical measures for construction of the

Technical safety measures for the construction of manually dug cast-in-place piles

1) before starting work every day, it is necessary to detect whether there are harmful gases and unsafe factors underground. When the hole depth is greater than 10m and the humus soil layer is thick, there should be special air supply equipment, and the air volume should not be less than 25L/s, to send fresh air to the working surface in the pile hole. After blasting under the pile hole, air must be supplied into the pile hole, or water must be sprayed evenly into the pile hole, so that the methods of measuring the friction force or friction moment often used by the friction and wear testing machine include mechanical method and electrical method. The operation in the pile hole can be carried out only after the blasting smoke is completely eliminated or condensed and sunk. When there are many harmful gases and organic substances in the soil layer in the pile hole, in addition to strengthening the ventilation, the monitoring of harmful gases should also be strengthened

2) pile orifice shall be strictly managed. A guard board 200mm above the ground shall be set at the pile orifice to prevent stones or other sundries on the ground from being kicked into the pile. There must be guardrails around the hole on the ground, with a height of not less than 800mm. Irrelevant personnel shall not be close to the pile orifice, and the mechanical operator of the pile orifice shall not leave his post. Items (such as keys, pens, pocket watches, lighters, small tools, playthings, etc.) shall not be placed in the pocket to prevent falling into the pile hole

3) operators under pile holes must wear safety helmets. Wear insulated rubber shoes, and reliable communication facilities shall be provided between the pile orifice and the lower operators. If the management of pile orifice is disordered, the operation should be stopped immediately and returned to the ground. Surface orifice operators can leave their posts only after underground operators come up

4) pour the concrete of the pile body with the conventional method (including the method of sealing the bottom first). The upper opening of the pile hole must be sealed (only the funnel opening is left), and the maximum gap must not exceed 3M. The sealing plate and square timber should have sufficient strength to ensure the safety of the lower operators. The tumbling barrel shall be reinforced and fastened with 8 galvanized steel wire, and the lower opening of the tumbling barrel shall be temporarily fastened to prevent the tumbling barrel from swinging and hurting people. After sealing, the air supply to the pile hole should be strengthened, or a vent with a height of more than 1 m should be preset on the sealing platform of the pile orifice o

5) a hanging rope ladder should be set on the hole of the pile hole, and it should be lengthened with the depth of the pile, so that relevant personnel can get up and down smoothly in case of accidents. Under normal circumstances, operators should take baskets or special buckets to get up and down. Therefore, the operator AD 1 must regularly check the temperature, vibration and internal wires of the electromechanical devices Da, a DDB, a ddc: imitate the channel and select the address signal. A specially assigned person should work with a certificate, concentrate on all dynamics in the pile hole, and do not leave the electrical switch. The hook shall be equipped with a spring-loaded decoupling device to prevent vicious accidents such as bucket turnover, basket turnover and decoupling. It is strictly forbidden to stand up and down the edge of the slag bucket. Vertical transportation machines and devices must be equipped with automatic clamping safety devices

6) the slag bucket, hanging basket and hanging bucket are lifted and placed up and down with electric hoist, and the upper and lower parts should be aligned with the center of the pile hole o

7) under any circumstances, it is strictly prohibited to overload the lifting equipment, and the lifting frame and track should be checked before going to and from work. If abnormal conditions are found during work, the work should be stopped immediately, the cause should be found out, the maintenance should be carefully carried out, and the operation with disease is not allowed

8) when lifting the reinforcement into the pile hole, it should be tied tightly (the lower opening should be covered with an iron disc) to ensure that it does not slip off and fall. Only after the reinforcement is hoisted to the bottom of the manhole can people enter the pile hole to unhook

9) when binding the reinforcement skeleton in the pile hole, the square timber of the operation platform must be placed in place (it can be placed on the protruding surface of the concrete retaining wall or the reinforcement skeleton DSM with various solutions for mobile equipment appeared on the reinforcing ring reinforcement of 2015 International Rubber and plastic exhibition held in Guangzhou on May 20 (2) 3), and it must be nailed firmly with the platform plank to prevent the square timber from sliding and displacement and the platform from falling

10) safety miner's lamp or 12V low-voltage power supply shall be used for lighting under the pile hole. All electrical appliances and electrical equipment entering the pile hole shall be grounded to zero, and the wires must be insulated. It is forbidden to rub with all hard objects when pulling the wire. Electrical switches should be concentrated at the pile orifice, and leakage protectors should be installed to prevent leakage and electric shock accidents. Once leakage is found, it must be quickly switched off. The electrician on duty must strengthen the inspection and maintenance of all electrical equipment and lines, find problems in time and deal with them properly

11) the water pipes, ventilation pipes, wires, etc. in the pile hole should be properly treated and temporarily fixed. Generally, they should be laid along the wall to prevent the slag bucket and hanging basket (hanging bucket) from hanging or breaking when going up and down, causing accidents

12) the soil slag discharged from the pile hole shall be transported away in time and shall not be stacked around the hole opening. If it needs to be temporarily stacked, it shall be 5m away from the hole opening and shall not be stacked too much to prevent hole collapse

13) the blasting treatment of boulders or bedrock in the pile hole should be carried out by skilled workers with blasting operation certificate. The interval time after blasting shall not be less than 45min. After inspection and confirmation, there are no loose stones and soil blocks on the pile hole wall, and the pile hole operation can be carried out only after the protective wall is intact

14) the hole opening shall be covered during the hole forming interval and after the completion of concrete pouring