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Punched Grouted Piles Punched grouted piles are a type of grouted piles. Piled piles are formed directly on the pile position in situ, and then filled with concrete or reinforced concrete into the hole. Punching pile construction punching machine impact hole, for the mud wall into the hole. Punching piles are made by impact drilling and then filling the holes with concrete or reinforced concrete, mainly used for making holes in rock and soil layers, when making holes, the punch cone drill bit will be lifted to a certain height and then crushed the rock layer by free falling impact, and then use slag emptying cylinder to pull out the slurry in the holes.
Edit this section of the attention of the punched pile
First, the construction and use of the conduit should be in accordance with the following provisions: 1, the wall thickness of the conduit should not be less than 3mm, the diameter of the conduit is suitable for 200 ~ 250mm; the diameter of the production should not be more than 2mm, the length of the conduit section can be determined according to the requirements of the process, the bottom length of the pipe should not be less than 4m, and the other section length of 2.53m, the joints are suitable for The use of double-threaded square buckle quick connector; 2, the conduit should be used before the test assembly, test pressure, water pressure can be taken as 0.6 ~ 1.0MPa; 3, each filling should be cleaned inside and outside the conduit. Second, the quality control of underwater concrete filling should meet the following requirements: 1, start filling concrete, the distance from the bottom of the conduit to the bottom of the hole should be 300 ~ 500mm; 2, there should be enough concrete reserves, the conduit should be buried in the concrete below the filling surface should not be less than 0.8m; 3, the conduit should be buried in the concrete depth of 2 ~ 6 m. Prohibit conduit to put out the surface of the concrete filling, and should be controlled to lift the conduit speed, there should be a person to measure the speed. The speed of the conduit, there should be a person to measure the depth of the conduit and tube inside and outside the height difference between the concrete filling surface, fill in the underwater concrete filling records; 4, filling underwater concrete must be continuous construction, the filling time of each pile should be controlled according to the initial plate of the first set time of concrete, the failure of the filling process should be recorded for the record; 5, should be controlled for the last time to fill in the amount of overfilling the height of 0.8 ~ 1.0m, chiseling off the height of the flood slurry It must be ensured that the concrete strength of the exposed pile top reaches the design grade. After each pile is grouted to the top, attention should be paid to the quality of over height of 800mm, and the contractor should check the elevation. The tenderer shall check the elevation according to the design elevation plus 800mm. Third, the underwater filled concrete should comply with the following provisions: 1, the underwater filled concrete must have good compatibility, with the ratio should be determined by test; slump should be 180 ~ 220mm; cement dosage should not be less than 360kg/m3 (when mixed with fly ash cement dosage can not be subjected to this limitation); 2, the sand content of the underwater filled concrete is suitable for 40% ~ 50%, and it is preferable to use the medium-coarse sand; The maximum size of coarse aggregate should be less than 40mm; and should meet, coarse aggregate can choose pebbles or gravel, the aggregate size shall not be greater than 1/3 of the minimum clear distance between the reinforcement spacing. 3, underwater filled concrete should be mixed with additives. 4, the initial amount of concrete must be calculated to determine the initial amount of concrete: the general requirements of the conduit inserted into the pile concrete depth of 1500mm; 5, the depth of the hole must meet the design requirements, the thickness of the slag is strictly prohibited to be greater than 50mm. 6, the initial amount of concrete for this project shall not be less than 1.8m3. The initial amount of concrete to ensure that all the water in the conduit to be pressurized, and can be the conduit initially buried in the concrete 1 ~ 1.5m deep.