Safety technical construction measures for the hot

Safety technical construction measures for foundation engineering

1 safety requirements for pile foundation construction

1.1 safety requirements for driving and clearing concrete precast piles in the workplace. When using the pile crane to lift the pile, the vertical distance between the pile and the pile frame should not be greater than 4m, and the eccentric lifting distance should not be greater than 2.5m: when lifting the pile, it should be slow, and the pile body should be tied with cables in more than two different directions, and the pile body should be stabilized by manual control. Before lifting the pile, the hammer shall be lifted to a certain position and fixed firmly to prevent the pile hammer from falling when lifting the pile. When lifting, the lifting point must be correct, the speed should be uniform, the pile body should be stable, and the pile frame should be equipped with cable wind rope when necessary. The attachments on the pile body shall be removed, and personnel are not allowed to pass under the pile after lifting. In case of interference between pile lifting and pile transportation, pile transportation shall be stopped

when inserting the pile, it is strictly forbidden to stretch your hands and feet between the pile and the gantry. When correcting piles with crowbars or sampans, don't use force to teach everyone that it's better to be too hard. During pile driving, pile caps and liners suitable for the pile type, pile frame and pile hammer shall be adopted, and any damage shall be repaired or replaced in time. The hammering should not be eccentric, and the starting falling distance should be small. In case of sudden increase of penetration, sudden inclination and displacement of pile body, serious damage of pile head, fracture of pile body, serious rebound of pile hammer, etc., the hammering should be stopped, and the operation can be continued after taking measures. During pile driving, the center of pile driving, pile hammer and pile shall be on the same axis

when pulling out piles, appropriate rope buckles should be selected, and the force must be applied slowly during operation. Pay attention to the changes of pile frame and steel wire rope at any time. After the pile is pulled out, the ground holes must be backfilled in time or automatically shut down for capping

1.2 safety requirements for the construction of immersed cast-in-place pile: after the pile pipe is sunk to the design depth, the pile cap and pile hammer should be raised to more than 4m and locked, and then the pile pipe can be inspected or concrete can be poured. The earrings and riding spring screws on the chassis should be tied firmly with steel wire rope to prevent falling and hurting people when they are broken. When the earrings fall, the control rope must be used, and it is forbidden to let them fall freely. If there is a hole after the sinking cast-in-place pile is pulled out, the orifice should be sealed with a cover plate to prevent accidents

1.3 safety requirements for the construction of punching and bored cast-in-place piles. Before pouring concrete for bored cast-in-place piles, the orifice should be covered with a cover plate, and no heavy objects are allowed to be stacked nearby. No one is allowed to enter the falling hammer area during the operation of punching and grabbing cone or punching hammer. During the operation of various hole forming drills, they should be placed stably to prevent accidents caused by the sudden collapse of the drill or the sudden fall of the drill

2 safety requirements for the construction of manually dug cast-in-place piles

2.1 general safety requirements manually dug cast-in-place piles (hereinafter referred to as dug piles) are suitable for projects with good engineering geological and hydrogeological conditions, shallow bearing stratum and large single pile bearing capacity. Without reliable technology and safety measures, it is not allowed to carry out hole digging pile construction in sandy soil with high groundwater level or muddy soil layer with large thickness. Generally, the hole depth of dug pile should not exceed 40m. The strength grade of the retaining wall concrete of the dug pile shall not be lower than C15. In karst, we can also choose the most suitable change experimental machine according to the following points: 1 Maximum torque: when the digging pile is used in the maximum torque area of the tested parts or in the rock stratum with uneven weathering, interlayer and large changes in soft and hard, it is advisable to drill an exploration borehole at each pile or column position. The drilling depth should generally reach 3 times the pile diameter below the hole bottom of the dug pile, so as to judge whether there are holes, broken zones or weak intercalations in the bedrock within the depth range. The buildings (structures) adjacent to the site shall be carefully inspected together with relevant units and owners before construction, and the original cracks and other conditions of the buildings (structures) shall be recorded for future reference. Reinforcement measures shall be taken in advance for adjacent houses that may be endangered by hole digging and pumping. Drainage ditches and water collecting wells should be set up on and around the site, and the treatment plan of mud and waste residue should be formulated. The excavation route at the construction site shall be unblocked

2.2 construction safety measures workers engaged in hole digging pile operation should be healthy young men, and should pass the health examination. They can enter the construction site only after passing the safety operation training and examination, such as underground, overhead, electricity, hoisting and simple mechanical operation

in order to prevent the hole wall from collapsing, a reliable construction method of supporting the hole wall should be adopted according to the pile diameter and geological conditions. The orifice operation platform shall form a stable system by itself to prevent it from being pulled down when the retaining wall sinks. All equipment, facilities, safety devices, tools and their accessories as well as personal protective equipment on the construction site must be inspected frequently to ensure their integrity and safe use. The workers must use steel ladders to get up and down the pile holes. It is not allowed to transport the workers by pulling the rope manually or step on the retaining wall flange to get up and down the pile holes. Nylon safety rope is set on the inner wall of the pile hole and extended to the working face with the increase of the excavation depth as a backup for emergency

after pile hole excavation, site personnel should pay attention to the changes of the ground and buildings (structures). If the pile hole is close to the old building or dangerous building, it must be reinforced before construction. It is also necessary to strengthen the observation of water gushing in the soil layer of the hole wall, and take timely treatment measures if abnormal conditions are found. The excavated earth and stone shall be transported away in time, and silt and debris shall not be stacked within 2m around the orifice. When motor vehicles pass, preventive measures shall be taken and operations in the hole shall be suspended to prevent hole collapse due to extrusion. When the excavation depth of the pile hole exceeds 5m, the gas detector shall be used to detect the toxic gas before the commencement of work every day, and the hole operation can be carried out only after the gas in the hole is confirmed to be normal