Interpretation of Construction Technology in Construction Engineering 1 Range Piling of precast reinforced concrete piles This technical standard is applicable to the construction of precast reinforced concrete piles in industrial and civil buildings. 2 Construction preparation 2.1 Material and main machinery: 2.1.1 Prefabricated reinforced concrete piles: specifications and quality must meet the design requirements and construction specifications, and have factory certificates. 2.1.2 Electrode (for connecting piles): The type and performance must meet the design requirements and the relevant standards. Generally, E4303 is suitable. 2.1.3 Steel plate (for connecting piles): Material and specifications meet the design requirements, and low carbon steel is suitable. 2.1.4 The main machines are: diesel pile driver, welding machine, pile cap, pile carriage.Cables, wire ropes, steel cushion plates or channel steel, and wood folding rulers, etc. 2.2 Operating conditions: 2.2.1 The axis and elevation of the pile foundation have been measured, and the pre-inspection procedures have been completed after inspection.The axis and elevation of the pile foundation should be set at places not affected by piling, and should be properly protected. 2.2.2 Handle obstacles at high altitude and underground.If it affects the use or safety of adjacent buildings or structures, effective measures shall be taken in conjunction with relevant units to deal with it. 2.2.3 According to the axis, the line of pile position is set out, and the pile position is nailed with a wooden fence or steel head, and marked with white ash, so as to be easy to hit. 2.2.4 The site should be compacted flat, drainage smooth, to ensure the movement and stability of the pile machine vertical. 2.2.5 Drive test piles.Before construction, test piles must be driven with fewer than 2 logs.Determine penetration and check the suitability of pile driving equipment, construction technology and technical measures. 2.2.6 It is necessary to select and determine the entry and exit routes of pile drivers and pile driving sequence, formulate construction plans, and make a good technical presentation. 3 Operation process 3.1 Technological process: 3.2 In-place pile driver: When pile driver is in place, it should be in the right position to ensure vertical stability and no inclination or movement occurs during construction. 3.3 Lifting prefabricated pile: Firstly tie the wire rope and rope used for hanging pile, then tie the rope around the hanging ring at the top of the pile, generally not more than 30 cm. Then start the machine to lift the prefabricated pile, so that the tip of the pile is vertically aligned to the center of the pile position, slowly lowering and inserting into the soil, the position should be accurate; and then fasten the pile cap or pile hoop at the top of the pile, the rope can be removed. 3.4 Stabilizing piles.After the tip of the pile is inserted into the pile position, a small drop distance cold hammer is used 1 to 2 times, and the pile is put into a certain depth, then the pile is vertically stable.Short piles within 10m can be visually measured or corrected by two-way drop; piles above 10m or driven by drop or theodolite must be corrected by two-way drop or theodolite, not by visual measurement.When the pile is inserted, the deviation of verticality should not exceed 0.5%.Before driving into the pile, the ruler should be set on the side of the pile or on the pile frame for observation and record in construction. 3.5 Piling: When driving with drop hammer or single-action hammer, the maximum drop distance of hammer should not exceed 1.0m.When driving piles with diesel hammer, the hammer should run normally. 3.5.1 Piling should be driven by heavy hammer with low impact. The selection of hammer weight should be based on engineering geological conditions, pile type, structure, density and construction conditions. 3.5.2 Piling sequence is based on the design elevation of the foundation, first deep and then shallow; according to the specifications of the pile, first large and then small, first long and then short.Because of the different density of piles, they can be carried out symmetrically from the middle to two centers or around, or from one side to a single direction. 3.6 Pile connection 3.6.l In the case of insufficient pile length, the pre-embedded parts on the surface of the prefabricated piles shou