Introduction of manual digging pile technical disclosure construction project?

technical disclosure of manual digging pile? The following information about the technical disclosure of manual digging piles is brought by Zhongda Consulting for your reference.

1. Construction technology of manual digging pile

1. Digging:

(1) The retaining wall of the hole ring in the first section should be 1-3mm thicker than the retaining wall below, and should be 2-25mm higher than the site ground, and the lap length between the upper and lower retaining walls should not be less than 5 mm.

(2) In order to ensure the integrity of the breast wall concrete, φ8 reinforcement shall be uniformly arranged as Rachel reinforcement according to the soil condition of the breast wall to avoid disconnection and sinking. If the breast wall details are designed, the construction shall be carried out according to the design requirements.

(3) When pouring concrete for retaining wall, knock the formwork and insert it with bamboo and wooden sticks, and do not pour concrete when the formwork is submerged by water in the pile hole. According to the soil conditions, the accelerator should be used as much as possible to meet the design strength requirements as soon as possible. Honeycomb and water leakage are found in the retaining wall, which should be blocked and diverted in time to prevent water from flowing into the hole through the retaining wall and ensure the strength and safety of the retaining wall concrete.

(4) The internal formwork removal of the retaining wall concrete depends on the temperature and other conditions, and can generally be carried out after 24 hours, so that the concrete has a certain strength to retain the soil.

(5) After the formwork removal of the concrete retaining wall in the first section, the axis position shall be calibrated on the retaining wall, and the relative horizontal elevation shall be recorded in the retaining wall in the first circle with a level, as a basis for controlling the position and verticality of the pile hole and determining the depth and elevation of the pile top.

(6) The construction personnel must be familiar with the geological conditions of the excavated hole, and check frequently, and pay attention to the changes of the soil layer. When quicksand and a large amount of groundwater affect the safety of digging, effective protective measures should be taken immediately before the construction can continue.

(7) In case of flowing silt or quicksand, the hole wall shall be constructed with steel liners. For the construction section that is easy to collapse, it is necessary to dig, proofread, and accept, that is, pour concrete for retaining wall, so as to ensure the compactness of concrete and avoid leakage.

(8) For piles with a small amount of quicksand, first dig the pile hole without quicksand nearby to make it play the role of a water collecting well. The water collecting well should be selected above the groundwater flow. When pumping water with a pump, the pile hole and the nearby groundwater level should be lowered to the bottom of the well, so as to prevent the bottom of the well from being flooded.

(9) When the ground is close to the original building (structure) due to a large amount of pumping groundwater, and the foundation and platform sink, irrigation points should be set up near the pumping well hole or the excavated but unfinished piles should be used for irrigation, so as to maintain the water pressure balance and stabilize the soil.

(1) When quicksand layer is found, the height of each retaining wall should be reduced, which can be 3-5CM, and concrete should be added.

(11) deal with the pile foundation of quicksand, and strive to finish the pile position of quicksand in the dry season, so as to avoid the increase of groundwater level and the great hydrodynamic pressure in the rainy season, which will increase the construction difficulty.

(12) When the end of the pile goes into the rock, and it is difficult to operate by hand pneumatic drilling, the silent crushing method can be adopted. If small-scale blasting with explosives is used, a blasting scheme should be worked out and approved by the relevant department (Public Security Bureau). During in-hole blasting, all other in-hole operators at the site must be evacuated and operated in strict accordance with the blasting regulations.

(13) When enlarging the foot at the pile end, the construction, design unit and quality supervision department shall be informed in time to identify the rock sample at the bottom of the hole, and the bottom enlargement work shall be carried out only after the identification meets the requirements. At the end of the hole, it is necessary to clean up the sludge of the retaining wall and the residual debris floating soil at the bottom of the pile, remove the accumulated water, accept it with the consent of the supervision and inspection, and handle the signing and recognition procedures. Should quickly organize pouring pile core concrete, so as not to soften the soil layer by soaking.

2. Fabrication and placement of reinforcing cage

(1) Measures should be taken to prevent deformation during fabrication, transportation and installation of cage reinforcement of manual digging piles.

(2) The thickness of the protective layer of the main reinforcement concrete of the reinforcing cage should not be less than 7MM. The thickness of protective layer can be prefabricated concrete pad or iron pad, which can be bound or welded at the design position on the outside of reinforcing cage. (3) When hoisting the reinforcing cage into the hole, it is forbidden to collide with the hole wall. When pouring concrete, measures should be taken to correct the design elevation and fix the reinforcing cage position.

(4) If the reinforcing cage is too long and needs to be connected in sections, the number of welding seams and joints shall meet the requirements of GB524-92.

(5) For the allowable deviation of reinforcing cage production, refer to the allowable deviation table of digging pile construction.

3. Pouring concrete

(1) The concrete of the pile body shall be completed from the bottom of the pile to the elevation of the pile top at one time. In case of power failure and other special reasons, when construction joints must be left, appropriate short steel bars can be inserted around the concrete surface. Before pouring new concrete, the joint surface must be cleaned, and there can be no water and isolation substances.

(2) The concrete of cast-in-place pile body must be separated from the concrete surface by chute and string tube within 2M, and it is not allowed to shovel or reverse inclined materials at the wellhead, so as to avoid concrete segregation and affect the overall strength of concrete.

(3) in the process of pouring concrete, pay attention to prevent groundwater from entering, and there must be no water layer with a thickness of more than 5MM, otherwise, try to drain the water layer on the concrete surface with a catheter before pouring concrete. If the water seepage is too large, it should be constructed according to the underwater concrete regulations.

(4) The concrete is poured and inserted, and the method of combining plug-in vibrator with manual insertion is adopted to ensure the compactness of concrete.

(5) When concreting the cast-in-place pile body, the digging operation within 1M adjacent to it should be stopped, and no one should be left at the bottom of the hole.

(6) When concreting the cast-in-place pile body, test blocks shall be retained, and each pile shall not be less than one group (3 pieces), and the test report shall be submitted in time.

4. Quality standard

A. Guarantee project

(1) The raw materials and concrete strength of concrete must meet the design requirements and construction specifications.

(2) The amount of concrete poured into the pile core shall not be less than the calculated volume.

(3) The elevation of pile top and laitance treatment of pouring concrete must comply with the design requirements and construction specifications.

(4) The hole-forming depth and final hole bedrock must meet the design requirements.

(5) The variety and quality of reinforcement and covered electrode model must meet the design requirements and relevant standards.

(6) welded joints of steel bars must conform to the special provisions on welding and acceptance of steel bars.

B, basic projects

(1) The concrete production must be cut according to the concrete mixture ratio, and the water consumption must be strictly controlled.

(2) When pouring concrete, it must vibrate with the pouring, and the pouring height shall not be greater than 8MM at a time.

(3) The lap joint and welding length of the main reinforcement of the reinforcing cage must comply with the regulations. Welding shall be staggered, and the number of joints within the range of 35 times the diameter of steel bars shall not exceed half of the total number of steel bars.

(4) Stiffening hoops, stirrups and solder joints of reinforcing cage must be dense and firm, and the number of missing solder joints shall not exceed the requirements specified in the specification.

(5) The center of the hole ring and the center line of the pile should coincide, and the deviation of the axis should not be greater than 2MM. On the same horizontal plane, the range of the two orthogonal diameters of the eyelet shall not be greater than 5 mm..

(6) The concrete thickness and reinforcement ratio should be as specified in the design, and even the concrete reinforcement should be inserted into the upper and lower retaining walls, which should not be less than half the height of the retaining wall. The diameter (outside and inside) error of the retaining wall is not more than 5cm.

C, allowable deviation

See the attached table:

5. Precautions for construction

1. Avoid common faults in engineering quality

(1) The pile concrete is not compact enough locally. Due to too thick primary pouring, poor vibration, insufficient insertion depth of vibrator, less vibration or vibration leakage, etc.

(2) the local strength of concrete is insufficient. Because the coarse aggregate is not weighed, the water consumption is not strictly controlled, the slump is too large, or the volume measurement of aggregate is not accurate enough, and the concrete mixture ratio is not adjusted in time under special circumstances.

(3) local segregation of concrete. Because the time of concrete mixing is less than 9 seconds, it is not uniform enough. The chute or string tube is too short, and the concrete on the car falls directly into the hole.

(4) The reinforcing cage is bent (banana-shaped) or twisted. Because the main reinforcement is not straightened in advance, and the stirrups are not welded on the equidistant points of the main reinforcement position, the uneven height of the bottom mat of the reinforcing cage is caused, which leads to the uneven thickness of the concrete protective layer of the main reinforcement, and even affects the quality.

(5) After the reinforcement cage is formed, the welding quality must be comprehensively checked by the on-site quality controller or the construction personnel. If the lap weld thickness of the main reinforcement is insufficient or the stirrup has missed the spot welding position, the welder should be immediately notified to repair the welding, and the concealed acceptance formalities should be handled in time.

(6) The final hole rock sample shall be sealed with plastic bags, and the original rock sample at the bottom of the hole shall be kept as far as possible for future reference.

II. Safety technical measures

(1) The problems and solutions put forward by the blue prints.the design should be recorded in detail, written as official documents or minutes of blue prints.the unit personnel who participated in the blue prints.the design should be signed and sealed, together with the construction drawing and construction scheme as the main construction basis.

(2) The minimum thickness of the retaining wall of the digging pile shall be not less than 1MM. Generally, the hole depth of digging pile should not exceed 25M. When the pile length is less than or equal to 8M, the diameter of the pile body (excluding the retaining wall, the same below) should not be less than .8M；; When the pile length is 8M to 15M, the diameter of the pile body should not be less than 1m; When the pile length is 15-5M, the pile body should not be less than 1.2M；; When the pile exceeds 2M, the diameter of the pile should be increased appropriately. When the clear distance between piles (including row piles) is less than 4.5M, interval excavation must be adopted (manual digging piles with enlarged bottom are counted as enlarged bottom).

(3) Before construction, the buildings (structures) near the site shall be inspected in detail with the relevant units and owners, and the original cracks and special conditions of the buildings (structures) shall be recorded with sandpaper for future reference. Reinforcement measures should be taken in advance for adjacent houses that may be endangered by digging holes and pumping water.

(4) The soil sample, rock penetration depth, hole bottom shape, pile diameter, pile length, verticality, pile top elevation and concrete strength of manual digging piles must meet the design requirements.

(5) In the process of artificial digging into the depth, targeted safety protection measures should be taken in case of quicksand, mud gushing, water gushing and harmful gas. All equipment, facilities, safety devices, tools and labor protection articles on the construction site need to be inspected frequently to ensure that they are in good condition and used safely.

(6) When the excavation depth of the pile hole exceeds 5M, a semi-circular safety protection net made of dense-eye steel bars shall be set on the retaining flange about 3M above the bottom of the hole. With the increase of digging depth, the workers must stand under the protective net when going up and down the bucket, stop digging, and pay attention to safety. Before starting work every day, put birds in the birdcage and hang them at the bottom of the pile hole for not less than 1 minutes. Only after checking that the birds are in normal ecological condition can they go into the well. When the hole depth exceeds 1M, the ground should be equipped with an air supply device to the hole, and the air volume should not be less than 25l/s.. Air supply should be increased in the fashion of hole drilling.

(7) Stairs must be placed in the pile hole and extended to the working face with the increase of digging depth for safe use. It is forbidden to operate after drinking, and smoking and using naked flame in the hole are not allowed. When lighting is needed, a safety miner's lamp or a safety lamp below 12V should be used.

(8) manhole covers and fences should be set up for the piles that have been poured with concrete and are being dug.

(9) After pumping water in the hole, the special power supply for pumping water must be cut off first, and the operators can work in the pile hole. It is forbidden to operate with power supply, and the operators in the hole with orifice shall pay close attention to the situation in the hole and shall not leave their posts without permission.

(1) All power wires in the construction site must be installed and removed by licensed electricians, and the electrical appliances must be strictly grounded, connected to zero and used with leakage protectors. The power consumption of each pile hole must be separated, and it is strictly forbidden to use one gate with multiple holes and one gate for multiple purposes. The "Technical Specification for Temporary Power Consumption in Construction Site" JGJ46-88 is strictly implemented.

Third, product protection

(1) The main reinforcement, stirrups and stiffening stirrups of the reinforcing cage should be stacked according to the variety, specification and length number to avoid bending and misuse.

(2) When the reinforcing cage is put into the pile hole, there must be a protective cushion block.

(3) The exposed main reinforcement of the pile head shall be properly protected and shall not be bent or cut off at will.

(4) When the strength of the pile head does not reach 5MPA, it shall not be crushed to avoid damage to the pile head.

detailed rules for the implementation of safety construction management regulations

article 1: in order to effectively prevent construction accidents, make the construction site orderly, meet the requirements of environmental protection, and ensure safe and accident-free production, these detailed rules are formulated according to the safety laws, regulations, procedures of the state and industry authorities and the relevant provisions of the army.

article 2: the project safety management shall implement the policy of "safety first, prevention first", adhere to strict management, and achieve strict responsibilities, strict systems, strict discipline and strict assessment.

article 3: the goal of project safety production is: no accidents due to construction, and the construction site is orderly and meets the requirements of environmental protection.

1. Strictly implement the "Nine Prohibitions" regulation in the safety management of engineering construction, and educate the construction personnel to use the five refusal rights.

(1) Nine prohibitions on safety management

(1) No operation is allowed without safety technical measures and safety disclosure;

(2) No operation is allowed until the safety facilities are complete and effective;

(3) No operation is allowed without taking effective safety measures on the dangerous working surface;

(4) If hidden dangers of accidents are found and not eliminated in time, no operation is allowed;

(5) Do not use safety labor protection articles according to regulations, and are not allowed to work at his post;

(6) Non-special operators are not allowed to engage in special operations;

(7) If the safety protection devices of mechanical and electrical equipment are not complete, no operation is allowed;

(8) Not familiar with the performance of machinery, equipment and tools, and not allowed to use them;

(9) New workers are not allowed to work at their posts without training or failing the training examination.

(2) Five rights of refusal

(1) When arranging the construction and production tasks, if no safety measures are arranged, the construction personnel have the right to refuse to work at their posts;

(2) If the site conditions have changed and the safety measures can't keep up, the construction personnel have the right to refuse the construction;

(3) If the cadres command in violation of regulations, the construction personnel have the right to refuse to obey;

(4) If the equipment safety protection device is unsafe, the construction personnel have the right to refuse to operate;

(5) If the conditions at the job site deteriorate and accidents are likely to occur, the construction personnel have the right to refuse to enter the job site without taking corresponding measures.

second, the construction site must be warned in dangerous places, and pedestrians must have eye-catching safety production slogans and protective measures. Operators should abide by the mandatory standards, rules and regulations and operating procedures for safe construction, correctly use mechanical equipment to construct mechanical appliances and safety protection appliances, and maintain them regularly.

third, the construction site should strengthen fire control management, determine the person in charge of fire control safety, formulate various fire control safety management systems and operating procedures such as using fire, electricity and inflammable and explosive materials, equip with fire control measures and fire extinguishing equipment, set fire prevention and purchase signs, and supervise their implementation.

Fourth, the following safety measures should be implemented in winter, rainy season and night construction:

(1) After the snowstorm in winter, organize manpower to clean the working floor and scaffolding on site as soon as possible, and check whether there are hidden dangers in the scaffolding after the gale and whether the anti-skid measures are implemented. On-site scaffolding and tall facilities after heavy wind and snow must be inspected before they can be put into use;

(2) The personnel participating in winter construction should wear flexible clothes to prevent tripping or falling when working at heights;

(3) When using steam boilers on site in winter construction, qualified boilers with complete safety devices should be selected to train firemen.

(4) During construction in rainy season, electric shock and collapse are prone to occur, and the following problems should be paid attention to:

(1) Before the rainy season comes, electrical personnel should be organized to carefully check all electrical equipment on site. Outdoor equipment and switch boxes should have reliable rain-proof and moisture-proof measures, install leakage protection devices, and strictly check the binding insulation at the joints.

(2) Before the rainy season comes, tall equipment should be prepared.