Construction method for manufacturing PHC pipe pile by replacing cement with pipe pile residual slurry
By using pipe pile residual slurry instead of cement in the production of traditional cement concrete, the raw material formula and mixing steps are optimized, and the problems of solid waste emissions and carbon emissions of traditional cement concrete in the production process are solved, and a new type of building materials with high strength, low carbon and environmental protection are achieved.
Patent Information
- Application Number
- CN202411654112.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-19
- Publication Date
- 2025-03-07
AI Technical Summary
Traditional cement concrete has problems with solid waste emissions and carbon emissions during the production process, and the C-S-H gel content in the residual slurry of the pipe piles is low, resulting in insufficient strength.
The PHC pipe pile processing method is used to replace cement to make PHC pipe piles. By optimizing the raw material formula, including S105 ore powder, silica fume, cement, water, sand, stone and water reducer, specific stirring and reaction steps are carried out to improve the strength and environmental protection performance of concrete.
It has achieved a low-carbon and environmentally friendly production process, reduced solid waste emissions, improved the strength and construction performance of pipe pile slurry, and met the construction industry's demand for efficient and durable new building materials.
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Figure CN119569377A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of building materials, in particular to a method for manufacturing PHC pipe piles by replacing cement with pipe pile residual slurry. Background Art
[0002] Cement, as an important building material, has a history that dates back to ancient Rome. The earliest form of cement was invented by the Romans in the 3rd century BC, when they used a mixture of volcanic ash with lime and water to build strong building structures. This material, known as "Roman concrete," was unprecedented in its strength and durability, allowing Roman buildings such as the Colosseum and the Aqueduct to remain standing today.
[0003] With the advent of the Industrial Revolution, in the early 19th century, British engineer Joseph Aspdin invented modern Portland cement. He mixed limestone and clay, calcined them, and then ground them into powder. This new type of cement was named because its color was similar to that of Portland stone produced in Portugal. The emergence of Portland cement greatly promoted the development of the construction industry because it was not only simple to manufacture, but also low-cost and easy to mass-produce.
[0004] Concrete is a composite material made of cement, aggregate (sand, crushed stone or gravel) and water in a certain proportion. Concrete has a long history. As early as the 5th century BC, the Persian Empire began to use building materials containing cement. However, modern concrete in the true sense was developed in the mid-19th century with the popularization of Portland cement. Concrete quickly became one of the most widely used building materials in the world due to its excellent mechanical properties, plasticity and fire resistance.
[0005] Although cement and concrete have an irreplaceable position in the construction field, there are also some problems in their production and use. The traditional cement production process will emit a large amount of carbon dioxide and other greenhouse gases, which has a serious impact on the environment. According to statistics, the global cement industry produces about 7% of the total carbon emissions each year. In addition, the CSH gel content formed during the hardening process of traditional concrete is low, which directly affects the ultimate strength and durability of the concrete.
[0006] To address these issues, researchers and companies have been exploring new building materials and technologies that are more environmentally friendly and have better performance. Among them, the PHC pile method is an innovative solution. This method aims to improve the performance of concrete while reducing environmental impact by optimizing the raw material formula and using advanced production processes. For example, by adding auxiliary cementitious materials such as S105 mineral powder, the amount of cement can be reduced while maintaining the strength of concrete, thereby reducing carbon emissions. In addition, improved maintenance techniques and construction methods also help to improve the overall quality and service life of concrete.
[0007] In short, as society's awareness of sustainable development and environmental protection increases, the development of low-carbon, efficient and durable new building materials has become an important trend in the industry. PHC pile construction method is an advanced technology that emerged under this background. It can not only effectively solve the problems of traditional cement concrete, but also contribute to the green development of the construction industry. Summary of the invention
[0008] 1. Technical issues to be solved
[0009] In view of the shortcomings of the prior art, the present invention provides a method for producing PHC pipe piles by using pipe pile slurry instead of cement, which has the advantages of low cost, low carbon and environmental protection, and high strength. It solves the problem that the solid waste emissions and carbon emissions of cement concrete with traditional formulas do not meet the low carbon and environmental protection requirements during the production process, and the CSH gel content in the produced pipe pile slurry is low, resulting in insufficient strength.
[0010] (II) Technical solution
[0011] To achieve the above object, the present invention provides the following technical solution: a method for making PHC pipe piles by using pipe pile residual slurry to replace cement, comprising the following steps:
[0012] Step 1: Prepare raw materials: weigh S105 mineral powder, silica fume, cement, water, sand, stone and water reducing agent in the formula proportion;
[0013] Step 2: Add cement and 1 / 3 of the formula ratio of water into a concrete mixer and stir. After a hydration reaction of 2-2.5 minutes, add S105 mineral powder, silica fume and 2 / 3 of the formula ratio of water and stir evenly, and then carry out a chemical reaction for 3-5 minutes.
[0014] Step 3: After the reaction in step 2 is complete, add water reducing agent, sand and stone into the concrete mixer, mix them evenly, and the pipe pile slurry is prepared.
[0015] Preferably, the raw materials used in the pipe pile slurry in step one and their corresponding weight ratio ranges are: S105 mineral powder 11% to 15%; silica fume 9% to 13%; cement 9% to 11%; water 10.5% to 12.5%; sand 21% to 25%; stone 33% to 37%; and water reducer 1.24% to 1.31%.
[0016] Preferably, the raw materials used in the pipe pile slurry in step one and their corresponding weight ratios are: S105 mineral powder 13%; silica fume 10%; cement 9%; water 10.5%; sand 22%; stone 34%; and water reducing agent 1.26%.
[0017] Preferably, the raw materials used in the pipe pile slurry in step one and their corresponding weight ratios are: S105 mineral powder 14%; silica fume 13%; cement 11%; water 11%; sand 24%; stone 37%; and water reducing agent 1.30%.
[0018] Preferably, the step 2 comprises: after the cement and water are stirred, a hydration reaction begins to occur, generating CSH gel and a by-product CaOH2, and the chemical reaction equation is:
[0019] 2Ca3SiO5+7H2O→3CaO·2SiO2·4H2O+3Ca(OH)2
[0020] In the reaction formula, Ca3SiO5 is tricalcium silicate, H2O is water, 3CaO·2SiO2·4H2O is hydrated calcium silicate, i.e. CSH gel, and Ca(OH)2 is calcium hydroxide.
[0021] Preferably, the step 2 comprises: S105 mineral powder as a common mineral admixture for concrete is further hydrated with CaOH2 generated by cement hydration to generate CSH gel, and the reaction formula is:
[0022] SiO2+Ca(OH)2→CSH gel
[0023] In the reaction formula, SiO2 is silicon dioxide, Ca(OH)2 is calcium hydroxide, and CSH stands for calcium silicate hydrate. A large amount of CSH gel makes the concrete quickly cement and harden, thus generating strength.
[0024] Preferably, the silica fume is an ultrafine powder collected from the smoke of a silicon steel plant, with a particle size between 100 nanometers and 150 nanometers, containing a large amount of active silicon dioxide and having active chemical activity. It can accelerate the hydration rate of cement and mineral powder in concrete, and react with CaOH2 in the concrete system to produce more CSH gel.
[0025] Preferably, the S105 mineral powder is granulated blast furnace slag powder. Granulated blast furnace slag powder, as a hydraulic cementitious material, can accelerate its own hydrolysis and cementation in a strong alkaline environment to form a CSH gel that is the same as cement hydration.
[0026] Preferably, in step three, the speed of the stirrer is 1.5-1.7 m / s, and the mixing time is 1.0-1.5 min.
[0027] Preferably, the content of cementitious material in the residual slurry of the pipe pile in step three is 50% to 60%, and the pH value is between 10 and 12.
[0028] Compared with the prior art, the present invention provides a method for making PHC pipe piles by using the residual slurry of pipe piles instead of cement, which has the following beneficial effects:
[0029] 1. The raw material of the present invention, silica fume, is an ultrafine powder collected from the smoke of silicon steel plants, with a particle size between 100 nanometers and 150 nanometers. It contains a large amount of active silicon dioxide and is chemically active. It can accelerate the hydration rate of cement and mineral powder in concrete, and react with CaOH2 in the concrete system to produce more CSH gel.
[0030] 2. The raw material of the present invention, S105 mineral powder, belongs to granulated blast furnace slag powder. Granulated blast furnace slag powder, as a hydraulic cementitious material, can accelerate its own hydrolysis and cementation in a strong alkaline environment to form CSH gel that is the same as cement hydration. The present invention uses S105 grade granulated blast furnace slag powder with finer particle size, which has higher activity and generates more CSH gel.
[0031] 3. The present invention adopts high-strength concrete prepared by S105 mineral powder, silica fume, cement, water, sand, stone and water reducing agent to replace the cement concrete of traditional formula, and has the same construction performance and mechanical properties. Both mineral powder and silica fume are solid waste materials, which can reduce solid waste and be low-carbon and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Figure 1 It is a flow chart of the steps of the present invention. DETAILED DESCRIPTION
[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0034] See also Figure 1 The method of making PHC pipe piles by using the residual slurry of pipe piles to replace cement includes the following steps:
[0035] Step 1: Prepare raw materials: weigh the S105 mineral powder, silica fume (choosing silica fume as an environmentally friendly material can reduce the burden on the environment), cement, water, sand, stone and water reducing agent in the formula proportion;
[0036] Step 2: Put cement and 1 / 3 of the formula ratio of water (adding part of the water to the cement for preliminary hydration reaction first helps to control the hydration process and avoid too fast or uneven reaction) into a concrete mixer for stirring. After hydration reaction for 2-2.5 minutes, add S105 mineral powder, silica fume and 2 / 3 of the formula ratio of water and stir evenly (gradually add the remaining materials and continue stirring to ensure that all ingredients are fully mixed to improve the uniformity and stability of the concrete), and carry out chemical reaction for 3-5 minutes (giving enough time for the chemical reaction to fully proceed is conducive to forming more hydration products and enhancing the mechanical properties of the concrete);
[0037] Step 3: After the reaction in step 2 is complete, add a water reducer (adding a water reducer in this step can improve the workability of the concrete and make it easier to pump), sand and stone (sand and stone as aggregates provide the necessary volume and stability for the concrete, and at the same time are closely combined with the cement matrix to improve the overall strength) into the concrete mixer, mix them evenly (the mixture after sufficient stirring is more uniform, which helps to produce high-quality pipe pile slurry to meet engineering needs), and the pipe pile slurry is made.
[0038] Specifically, the raw materials used in the pipe pile slurry in step one and their corresponding weight ratio ranges are: S105 mineral powder 11% to 15%; silica fume 9% to 13%; cement 9% to 11%; water 10.5% to 12.5%; sand 21% to 25%; stone 33% to 37%; water reducer 1.24% to 1.31%.
[0039] S105 mineral powder: It is a mineral admixture that can improve the workability and durability of concrete.
[0040] Silica fume: A mineral admixture that can improve the strength and durability of concrete.
[0041] Cement: acts as a binder material that reacts with water to form hardened concrete.
[0042] Water: reacts with cement to form hydration products, causing concrete to harden.
[0043] Sand and stone: Act as aggregates, providing volume and stability to concrete.
[0044] Water reducing agent: It is used to reduce the amount of water used in the concrete mix while maintaining its workability.
[0045] Specifically, step 2 includes: after cement and water are mixed, hydration reaction begins to occur, generating CSH gel and by-product CaOH2, and the chemical reaction equation is:
[0046] 2Ca3SiO5+7H2O→3CaO·2SiO2·4H2O+3Ca(OH)2
[0047] In the reaction formula, Ca3SiO5 is tricalcium silicate (one of the main mineral components in cement), H2O is water, 3CaO·2SiO2·4H2O is hydrated calcium silicate, i.e. CSH gel, and Ca(OH)2 is calcium hydroxide.
[0048] Specifically, step 2 includes: S105 mineral powder, as a common mineral admixture for concrete, further undergoes hydration reaction with CaOH2 generated by cement hydration to generate CSH gel, and the reaction formula is:
[0049] SiO2+Ca(OH)2→CSH gel
[0050] In the reaction formula, SiO2 is silicon dioxide, Ca(OH)2 is calcium hydroxide, and CSH stands for calcium silicate hydrate. A large amount of CSH gel makes the concrete quickly cement and harden, thus generating strength.
[0051] Specifically, silica fume is an ultrafine powder collected from the smoke of silicon steel plants. Its particle size is between 100 nanometers and 150 nanometers. It contains a large amount of active silicon dioxide and is chemically active. It can accelerate the hydration rate of cement and mineral powder in concrete, and react with CaOH2 in the concrete system to produce more CSH gel.
[0052] Specifically, S105 mineral powder belongs to granulated blast furnace slag powder. As a hydraulic cementitious material, granulated blast furnace slag powder can accelerate its own hydrolysis and cementation in a strong alkaline environment to form a CSH gel that is the same as cement hydration (this method uses S105 grade granulated blast furnace slag powder with finer particle size, which has higher activity).
[0053] Specifically, in step three, the speed of the stirrer is 1.5-1.7 m / s, and the mixing time is 1.0-1.5 min. By setting the speed of the stirrer (1.5-1.7 m / s) and the mixing time (1.0-1.5 min), the uniformity of the mixture is ensured and over-mixing or under-mixing is avoided.
[0054] Specifically, the content of cementitious material in the residual slurry of the pipe pile in step three is 50% to 60%. The content of cementitious material is controlled between 50% and 60%, which not only ensures sufficient bonding force and strength, but also avoids cost increase and waste of resources caused by excessive use of cement. The pH value is between 10 and 12. Maintaining the pH value between 10 and 12 is conducive to the hydration reaction and also helps to maintain the durability of concrete. Appropriate cementitious material content and pH value help to form a denser and stronger concrete structure, thereby improving its bearing capacity and service life.
[0055] Example 1
[0056] The raw materials used in the pile slurry and their corresponding weight ratios are: S105 mineral powder 13%; silica fume 10%; cement 9%; water 10.5%; sand 22%; stone 34%; water reducing agent 1.26%.
[0057] Example 2
[0058] The raw materials used in the pipe pile slurry and their corresponding weight ratios are: S105 mineral powder 14%; silica fume 13%; cement 11%; water 11%; sand 24%; stone 37%; water reducing agent 1.30%.
[0059] Example 3
[0060] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 15%; silica fume 13%; cement 9%; water 12.5%; sand 21%; stone 37%; water reducing agent 1.28%.
[0061] Example 4
[0062] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 12%; silica fume 9%; cement 10%; water 10.5%; sand 23%; stone 35%; water reducing agent 1.29%.
[0063] Example 5
[0064] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 11%; silica fume 13%; cement 9%; water 11.5%; sand 21%; stone 36%; water reducing agent 1.31%.
[0065] Example 6
[0066] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 12.5%; silica fume 9.9%; cement 10.21%; water 11.8%; sand 22.5%; stone 34.77%; water reducing agent 1.29%.
[0067] Comparative Example 1
[0068] The raw materials used in the pipe pile slurry and their corresponding weight ratios are: cement 29%; water 15.5%; sand 22%; stone 34%; water reducing agent 1.26%.
[0069] Comparative Example 2
[0070] The raw materials used in the pipe pile slurry and their corresponding weight ratios are: silica fume 13%; cement 21%; water 15%; sand 24%; stone 37%; water reducing agent 1.30%.
[0071] Comparative Example 3
[0072] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 15%; cement 19%; water 14.5%; sand 21%; stone 37%; water reducing agent 1.28%.
[0073] Comparative Example 4
[0074] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 20%; silica fume 15%; water 12.5%; sand 23%; stone 35%; water reducing agent 1.29%.
[0075] Comparative Example 5
[0076] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 11%; silica fume 23%; water 11.5%; sand 21%; stone 36%; water reducing agent 1.31%.
[0077] Comparative Example 6
[0078] The raw materials used in the pile slurry and their corresponding weight ratio ranges are: S105 mineral powder 22.5%; silica fume 19.9%; cement 3.21%; water 14.8%; sand 22.5%; stone 34.77%; water reducing agent 1.29%.
[0079] All the raw material formulations of the embodiments and the corresponding raw material formulations of the proportions were made into pile slurries, and the prepared pile slurries were tested and compared in terms of compressive strength (MPa), flexural strength (MPa), fluidity (mm) and setting time (min). The test performance data are shown in the following table:
[0080]
[0081]
[0082]
[0083] According to the test data provided in the table, the performance of the residual slurry of the pipe piles of the embodiment and the comparative example is compared and summarized. The following are the comparison results of the compressive strength, flexural strength, fluidity and setting time:
[0084] Compressive strength (MPa): The compressive strength of Examples 1 to 6 ranges from 30.4 MPa to 32.1 MPa, and the compressive strength of Comparative Examples 1 to 6 ranges from 24.9 MPa to 26.5 MPa. The compressive strengths of the Examples are all higher than those of the Comparative Examples, indicating that the addition of S105 mineral powder and silica fume can improve the compressive strength of the pile slurry.
[0085] Flexural strength (MPa): The flexural strength of Examples 1 to 6 ranges from 5.8 MPa to 6.1 MPa. The flexural strength of Comparative Examples 1 to 6 ranges from 4.3 MPa to 4.9 MPa. The flexural strength of the Examples is higher than that of the Comparative Examples, indicating that the addition of S105 mineral powder and silica fume helps to improve the flexural performance of the pile slurry.
[0086] Fluidity (mm): The fluidity of Examples 1 to 6 ranges from 210 mm to 230 mm. The fluidity of Comparative Examples 1 to 6 ranges from 170 mm to 190 mm. The fluidity of the Examples is higher than that of the Comparative Examples, indicating that the addition of S105 mineral powder and silica fume can improve the workability of the pile slurry and make it easier to construct.
[0087] Setting time (min): The initial setting time of Examples 1 to 6 ranges from 110 min to 120 min, and the final setting time ranges from 230 min to 240 min. The initial setting time of Comparative Examples 1 to 6 ranges from 130 min to 150 min, and the final setting time ranges from 260 min to 270 min. The setting time of the Examples is shorter than that of the Comparative Examples, indicating that the addition of S105 mineral powder and silica fume can accelerate the setting speed of the pile slurry and shorten the construction period.
[0088] From the comparison of the above performance data, it can be seen that the embodiment is better than the comparative example in terms of compressive strength, flexural strength, fluidity and setting time. This shows that the addition of S105 mineral powder and silica fume has a positive effect on improving the performance of pipe pile slurry. The present invention can improve the construction performance and structural performance of pipe pile slurry by optimizing the raw material ratio, thereby improving the quality and service life of pipe piles.
[0089] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for making PHC pipe piles by using the residual slurry of pipe piles instead of cement, characterized in that: The following steps are involved: Step 1: Prepare raw materials: weigh S105 mineral powder, silica fume, cement, water, sand, stone and water reducing agent in the formula proportion; Step 2: Add cement and 1 / 3 of the formula ratio of water into a concrete mixer and stir. After a hydration reaction of 2-2.5 minutes, add S105 mineral powder, silica fume and 2 / 3 of the formula ratio of water and stir evenly, and then carry out a chemical reaction for 3-5 minutes. Step 3: After the reaction in step 2 is complete, add water reducing agent, sand and stone into the concrete mixer, mix them evenly, and the pipe pile slurry is prepared.
2. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 1, characterized in that: The raw materials used in the pipe pile slurry in step 1 and their corresponding weight ratios are as follows: S105 mineral powder 11% to 15%; silica fume 9% to 13%; cement 9% to 11%; water 10.5% to 12.5%; sand 21% to 25%; stone 33% to 37%; and water reducing agent 1.24% to 1.31%.
3. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 2, characterized in that: The raw materials used in the pile slurry in step 1 and their corresponding weight ratios are: S105 mineral powder 13%; silica fume 10%; cement 9%; water 10.5%; sand 22%; stone 34%; and water reducing agent 1.26%.
4. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 2, characterized in that: The raw materials used in the pile slurry in step 1 and their corresponding weight ratios are: S105 mineral powder 14%; silica fume 13%; cement 11%; water 11%; sand 24%; stone 37%; and water reducing agent 1.30%.
5. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 1, characterized in that: The second step includes: after cement and water are stirred, a hydration reaction begins to occur, generating CSH gel and byproduct CaOH2, and the chemical reaction equation is: 2Ca3SiO5+7H2O→3CaO·2SiO2·4H2O+3Ca(OH)2 In the reaction formula, Ca3SiO5 is tricalcium silicate, H2O is water, 3CaO·2SiO2·4H2O is hydrated calcium silicate, i.e. CSH gel, and Ca(OH)2 is calcium hydroxide.
6. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 1, characterized in that: The step 2 includes: S105 mineral powder as a common mineral admixture for concrete further undergoes hydration reaction with CaOH2 generated by cement hydration to generate CSH gel, and the reaction formula is: SiO2+Ca(OH)2→CSH gel In the reaction formula, SiO2 is silicon dioxide, Ca(OH)2 is calcium hydroxide, and CSH stands for calcium silicate hydrate. A large amount of CSH gel makes the concrete quickly cement and harden, thus generating strength.
7. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 1, characterized in that: The silica fume is an ultrafine powder collected from the smoke of silicon steel plants. Its particle size is between 100 nanometers and 150 nanometers. It contains a large amount of active silicon dioxide and is chemically active. It can accelerate the hydration rate of cement and mineral powder in concrete and react with CaOH2 in the concrete system to produce more CSH gel.
8. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 1, characterized in that: The S105 mineral powder is a granulated blast furnace slag powder. As a hydraulic cementitious material, the granulated blast furnace slag powder can accelerate its own hydrolysis and cementation in a strong alkaline environment to form a CSH gel that is the same as cement hydration.
9. The method for making PHC pipe piles by using residual pipe pile slurry to replace cement according to claim 1, characterized in that: In the step 3, the rotation speed of the stirrer is 1.5-1.7 m / s, and the mixing time is 1.0-1.5 min.
10. The method for making PHC pipe piles by using pipe pile slurry to replace cement according to claim 1, characterized in that: In the step 3, the content of the cementitious material in the residual slurry of the pipe pile is 50% to 60%, and the pH value is between 10 and 12.