Cement-soil pile anti-corrosion construction method of stiff composite pile

Abstract

The invention discloses an anti-corrosion construction method for a cement-soil pile of a stiff composite pile, geopolymer and polyacrylamide are doped into cement clinker for forming the cement-soil pile on the periphery of the composite pile, the cement clinker, the geopolymer and the polyacrylamide are as follows in percentage by mass: 30%-95% of the cement clinker, 15%-49% of the geopolymer and 0.5%-0.6% of the polyacrylamide, the sum of the dosage of the components is 100%, and the cement-soil pile is used for eliminating the corrosion influence. The corrosion influence of chloride ions and sulfate can be effectively eliminated, and the permeability coefficient of the peripheral cement soil body is smaller than 1 * 10 <-8 > m / s.

Description

Technical Field

[0001] The present invention relates to a construction method for anti-corrosion of cement-soil piles of a rigid composite pile. Background Art

[0002] During the construction of rigid composite piles, due to the ultra-high salinity and corrosiveness of some sites: chloride ions and sulfates erode traditional cement-soil piles, easily leading to damage to the pile head, cracks in the pile body, and deterioration of durability, which need to be addressed and solved. Currently, there is no good solution.

[0003] The high salt content and corrosiveness in the soil of some special regions (such as the Sabkha region in the Middle East) are also a major problem in pile foundation construction. Traditional pile foundation construction methods usually use conventional materials and anti-corrosion measures. However, in a high-salt environment, the durability of ordinary pile foundation materials and anti-corrosion measures is poor, easily leading to early corrosion of the pile foundation, thereby affecting its long-term bearing capacity and stability. Especially in soft soil layers, due to the strong water permeability, the corrosion problem is more prominent. Therefore, more corrosion-resistant pile foundation materials and more effective anti-corrosion technologies are needed to ensure the long-term reliability of the pile foundation in a harsh environment. Summary of the Invention

[0004] The purpose of the present invention is to provide a construction method for anti-corrosion of cement-soil piles of a rigid composite pile that can effectively solve the erosion of chloride ions and sulfates.

[0005] The technical solution of the present invention is as follows:

[0006] A construction method for anti-corrosion of cement-soil piles of a rigid composite pile, characterized in that: geopolymers and polyacrylamide are incorporated into the cement clinker for forming the cement-soil pile on the periphery of the composite pile, and the components and mass ratios are: cement clinker 30% - 95%, geopolymers 15% - 49%, polyacrylamide 0.5% - 0.6%, and the sum of the amounts of the above components is 100%, which is used to eliminate the corrosion effect, and the permeability coefficient of the peripheral cement-soil body < 1×10 -8 m / s;

[0007] The cement-soil pile on the periphery of the composite pile is constructed by using a pile-forming construction machine. The pile-forming construction machine includes a stirring rod. A powder outlet channel and a water outlet channel are arranged in the stirring rod. A spiral blade is arranged at the lower end of the stirring rod, a knife-shaped blade is arranged above the spiral blade, and a pH probe, a density probe, a humidity probe, and a pressure probe are arranged on the spiral blade; a tooth-shaped structure for tearing the soil layer is arranged on the lower surface of the spiral blade.

[0008] The core pile adopts a single-section ultra-high-strength pipe pile. Protective layers with a thickness of not less than 40 mm are provided on both the inner and outer surfaces of the single-section ultra-high-strength pipe pile. A thick-wall type pipe pile is used, the pile end is of a closed type, a finished pipe pile with a concrete pile tip is used, and the pile top is sealed with dry-hardened cement soil to prevent groundwater from entering the pile core from the pile top and the bottom of the pile; the static pressure method is used for the construction of the core pile.

[0009] In the case of a backfilled ground surface, before the construction of the core pile, the backfilled ground surface is compacted or mechanically rolled to be dense to avoid cracks in the pile body caused by the soil squeezing effect.

[0010] When manufacturing the pipe pile, ordinary Portland cement with a curing agent content of not more than 5% is used, and a steel bar rust inhibitor is added to the concrete.

[0011] When geopolymers and polyacrylamide are incorporated into the cement clinker to form the cement soil pile around the composite pile, overloading and stabilizing treatment is carried out after a period of time, including 1 to 3 times of overloading and stabilizing, with each time lasting more than 3 minutes, squeezing and compacting the plastic cement soil on the side of the pile, and directly reaching the preloading and pre-settlement hardening of the dry-hardened cement soil at the pile end through the stabilizing value matching the design ultimate load.

[0012] The present invention can effectively eliminate the corrosion effects of chloride ions and sulfates, and the permeability coefficient of the peripheral cement soil body < 1×10 -8 m / s. A special pile-forming construction machine is adopted, with high construction efficiency and good construction quality; overloading and stabilizing pre-settlement treatment is adopted, and the stress is concentrated at the pile end and stabilized to achieve active pre-settlement during construction. The present invention has excellent anti-corrosion performance and can be applied to the pile foundation construction in high-salt-content soils.

[0013] The following further describes the present invention in conjunction with the drawings and embodiments.

[0014] Figure 1 It is a schematic structural diagram of the pile-forming construction machine.

[0015] Among them: 1. Spiral blade; 2. Knife-shaped blade; 3. Powder outlet channel; 4. Water outlet channel; 5. pH probe; 6. Density probe; 7. Humidity probe; 8. Pressure probe; 9. Tooth-shaped structure. Specific embodiments

[0016] A construction method for anti-corrosion of the cement soil pile of a rigid composite pile, in which geopolymers and polyacrylamide are incorporated into the cement clinker for forming the cement soil pile around the composite pile, and the components and mass ratios are: cement clinker 54.5%, geopolymers 45%, polyacrylamide 0.5%, for eliminating the corrosion effect, and the permeability coefficient of the peripheral cement soil body < 1×10 -8 m / s;

[0017] The cement-soil pile around the composite pile is constructed by using a pile-forming construction machine. The pile-forming construction machine includes a mixing rod. A powder outlet channel and a water outlet channel are arranged in the mixing rod. A spiral blade is arranged at the lower end of the mixing rod. A knife-shaped blade is arranged above the spiral blade. A pH probe, a density probe, a humidity probe, and a pressure probe are arranged on the spiral blade. A tooth-shaped structure for tearing the soil layer is arranged on the lower surface of the spiral blade.

[0018] The core pile uses a single-section ultra-high-strength pipe pile. Protective layers with a thickness of not less than 40 mm are arranged on both the inner and outer surfaces of the single-section ultra-high-strength pipe pile. A thick-wall type pipe pile is used. The pile end is of a closed type. A finished pipe pile with a concrete pile tip is used, and the pile top is sealed with dry-hardened cement soil to prevent groundwater from entering the pile core from the pile top and the bottom of the pile. When constructing the core pile, the static pressure method is used for construction.

[0019] In the case of a backfilled ground surface, before constructing the core pile, the backfilled ground surface is first compacted or mechanically rolled to be dense to avoid cracks in the pile body caused by the soil squeezing effect.

[0020] When manufacturing the pipe pile, ordinary Portland cement with a curing agent content of not more than 5% is used, and a steel bar rust inhibitor is added to the concrete.

[0021] When geopolymers and polyacrylamide are incorporated into the cement clinker and the cement-soil pile around the composite pile is formed, overloading and pressure stabilization treatment is carried out after a period of time, including 1 to 3 times of overloading and pressure stabilization, with each duration being greater than 3 minutes, squeezing and expanding the plastic cement soil on the side of the pile to be dense, and directly reaching the preloading and pre-settlement hardening of the dry-hardened cement soil at the pile end through the pressure stabilization value matching the design ultimate load.

[0022] The reinforcement effect of the pile foundation is achieved, and at the same time, the functions of anti-corrosion and anti-seepage are possessed.

Claims

1. A cement soil pile anti-corrosion construction method for a rigid composite pile, characterized by: Geopolymer and polyacrylamide are added to the cement clinker of the cement soil piles outside the composite piles. The components and their mass proportions are: 30% to 95% of cement clinker, 15% to 49% of geopolymer, and 0.5% to 0.6% of polyacrylamide. The sum of the above components is 100%. It is used to eliminate the influence of corrosion. The permeability coefficient of the outer cement soil is less than 1×10 -8 m / s; The cement soil piles around the composite piles are constructed by a pile construction machine, which includes a stirring rod, a powder outlet channel and a water outlet channel are arranged in the stirring rod, a spiral blade is arranged at the lower end of the stirring rod, a knife-shaped blade is arranged above the spiral blade, and a pH probe, a density probe, a humidity probe, and a pressure probe are arranged on the spiral blade; a tooth-shaped structure for tearing the soil layer is arranged on the lower surface of the spiral blade; The core pile adopts single-section ultra-high-strength pipe pile. The inner and outer surfaces of the single-section ultra-high-strength pipe pile are provided with a protective layer with a thickness of not less than 40mm. Thick-walled pipe piles are adopted, and the pile ends are closed. Finished pipe piles with concrete pile tips are adopted, and the pile tops are sealed with dry hard cement soil to prevent groundwater from entering the pile core from the pile top and pile bottom. Static pressure method is adopted for core pile construction.

2. The cement soil pile anticorrosion construction method of the rigid composite pile according to claim 1 is characterized in that: When there is backfilled land, the backfilled land should be compacted or mechanically rolled before core pile construction to avoid cracks in the pile body caused by soil squeezing effect.

3. The cement soil pile anticorrosion construction method of the rigid composite pile according to claim 1 is characterized by: When producing pipe piles, ordinary Portland cement with a curing agent content of no more than 5% is used, and a steel bar rust inhibitor is added to the concrete.

4. The cement soil pile anticorrosion construction method of the rigid composite pile according to claim 1 is characterized in that: When geopolymer and polyacrylamide are added to cement clinker to form a cement-soil pile around the composite pile, overload and pressure stabilization treatment is carried out after a period of time, including 1 to 3 overload and pressure stabilization times, each time lasting more than 3 minutes, to compact the plastic cement soil on the pile side, and pre-compress and pre-settlement hardening of the dry and hard cement soil at the pile end by matching the pressure stabilization value of the design ultimate load.

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