It is strictly prohibited to use large machinery to directly excavate the soil.
When the drill pipe core pipe is full of the mixture, start pulling the pipe.
11 Curing and strength test During concrete pouring, a group of test blocks (not less than 3) shall be made every 100m3 of mixture, and at least one group shall be made every day.
If the drill pipe shakes or is difficult to drill during the hole forming process, slow down the footage, and timely check the perpendicularity of the drill pipe and the pile position, otherwise it is easy to cause deflection and displacement of the pile hole, or even damage the drill pipe and drilling tools.
It is prohibited to walk and disturb heavy machinery in the pile formed area to prevent damage to the pile head, which may cause the concrete on the pile top not to form.
If necessary, clean the drill pipe and drill bit after moving the machine.
The hole forming and pumping shall be closely coordinated to avoid any pause in the pile body grouting.
It is a variable strength pile with a certain strength made of crushed stone, stone chips, sand, fly ash mixed with cement and water, and is made of various pile forming machines.
No slope cracks are allowed.
Lay graded crushed stone cushion (cushion layer).
In some areas where the terrain fluctuates greatly and the cross slope is obvious.
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Pile position control: before the construction of each pile, determine whether the pile driver is aligned with the pile center by measuring the adjacent longitudinal and transverse pile positions with ruler.
6 After the hole of the CFG pile is formed to the design elevation, stop drilling and start pumping the mixture.
The weight shall be added once before the test and placed on the platform evenly and stably.
Indoor mix proportion test shall be carried out according to design requirements to select appropriate mix proportion.
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7 Before moving the machine, clear and identify the pile position of the next pile to ensure the accuracy of the pile position.
9 After the removal of all piles, the 0.5m pile head shall be removed, and the pile body soil within the pile length shall be excavated.
The excavation of the soil between the piles within the length of the protective pile shall be completed manually or by small machinery.
For construction setting out, use a steel drill rod with a diameter of 8mm to vertically drive a 20cm deep hole at the pile position, inject lime water or lime powder into the hole, insert markers into the hole, and use disposable wood and bamboo chopsticks to facilitate the search after the pile position is buried.
Spoil from drilling shall be transported to the designated site in time.
The slow maintenance load method is adopted for detection.
The lifting speed of pile forming should be controlled within 2m/min~3m/min, and the pile forming process should be continuous, so as to avoid stopping for materials due to problems in material supply.
Cement, fly ash, crushed stone, admixture and other raw materials selected for materials and mix proportions shall meet the requirements and relevant standards for quality acceptance of raw materials, and spot check shall be conducted as required.
Three steel chisels shall be used to chisel in horizontally at an angle of 120 degrees until the soil is broken, and then small chisels shall be used to repair the soil.
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The road camber shall be constructed according to the design requirements at the base of the CFG pile top elevation to ensure smooth drainage and no ponding.
Before the construction of each pile, the on-site personnel shall check the pile position alignment of the pile driver and the perpendicularity of the drill pipe, and the drilling can be started only after the requirements are met.
CFG pile is a kind of low strength concrete pile, which can make full use of the bearing capacity of soil between piles and transfer loads to deep foundation, and has good technical performance and economic effect.
It is strictly prohibited to pull the pipe before pumping the material.
CFG pile foundation treatment consists of CFG pile shaft, pile cap (plate) and cushion layer: pile+cap+cushion layer: pile test is to provide technical basis for the next soft foundation treatment project, including: (1) applicability of main equipment, model and quantity of supporting equipment; (2) The rationality of construction process and sequence shall be preliminarily determined according to the geological conditions, and the allocation of relevant personnel shall be adjusted by determining the construction control parameters and process time; (3) Whether the pile quality, the bearing capacity of single pile after treatment or the bearing capacity of foundation meet the design requirements.
Pay attention to curing and send it to the laboratory for 28d strength test.
During unloading, the unloading amount of each stage shall be taken as 2 times of the staged load during loading..
CFG pile foundation detection I: pile foundation detection (I) Static load test Static load test is an in-situ detection method that applies the actual load of the simulated building step by step and simultaneously observes the corresponding deformation of the foundation under the in-situ condition.
Pile length control: make clear length identification on the pile driver body, and use reflective materials for identification to facilitate construction control at night; The minimum scale of the sign is generally 50cm or 25cm; According to the footage mark on the drilling tower body, when the hole reaches the design elevation, drilling shall be stopped.
In the construction preparation area, remove the vegetation on the original surface of the ground within the scope of the subgrade, and dig out the roots of trees.
By measuring the relative distance between the plumb ball and the upper and lower ends of the drill pipe, the bystander shall determine whether the verticality deviation of the machine body meets the specification or design requirements to ensure that the allowable deviation of the CFG pile verticality is not more than 1.0%.
4 After the drilling rig is in place and the drilling rig is in place, the pile driver shall hang a two-way plumb ball.
Construction technology CFG pile construction can be divided into seven sections according to the construction technology, namely: construction preparation area, survey and setting out area, pile foundation construction area, soil removal area between piles, pile head cutting area, pile foundation detection area, and pile cap construction area.
The removal of the pile head shall be completed manually.
Click the name card below for interior design drawings | Subscribe to our CFG pile is the abbreviation of Cement Fly ash Gravel, which means cement fly ash gravel pile.
The reaction device for the test shall be a weight platform device, and the weight shall not be less than 1.2 times of the preset maximum test load.
The site shall be leveled to check, remove and protect the upper and underground pipelines in the construction site.
The test loading device shall be hydraulic jack, and the maximum loading value shall not be less than 2 times of the design pressure.
5 At the beginning of drilling, close the drill bit valve, move the drill pipe downward until the drill bit touches the ground, and start the motor to drill slowly first and then quickly, which can not only reduce the shaking of the drill pipe, but also check the drilling deviation for timely correction.
10 During pile foundation inspection and construction, pay attention to check the sealing of pump pipe to prevent water leakage.
The loading shall be carried out in 10 stages, and the load of each stage shall be 1/10 of the maximum load, and the first stage can be loaded twice of the graded load.