Super high-rise pumping pipeline moistening mortar

Abstract

The invention relates to the field of pumping concrete, and particularly discloses pipe moistening mortar for a super high-rise pumping pipeline. The super high-rise pumping pipeline lubricating mortar is prepared from the following components in parts by weight: 400 to 450 parts of cement, 900 to 1000 parts of fine aggregate, 10 to 30 parts of conditioning agent, 200 to 250 parts of water, 5 to 15 parts of additive, 100 to 120 parts of fly ash and 50 to 70 parts of slag powder. The pipe lubricating mortar for the super high-rise pumping pipeline has the advantages that the fluidity is enhanced, the pumping lubrication degree is improved, and the pumping pipeline is prevented from being easily rusted.

Description

Technical Field

[0001] The present application relates to the field of pumping concrete, and more specifically, to a super-high-rise pumping pipeline lubricating mortar. Background Art

[0002] In modern urban construction, super high-rise projects are an important part of the city skyline, and the complexity and challenges of their construction technology are becoming increasingly prominent. In particular, during the concrete pumping process, due to the particularity of super high-rise buildings, such as the delivery pipeline is about 500 meters long, and even the longest delivery pipeline is more than 650 meters long, the entire pumping process faces many technical difficulties.

[0003] The pressure of the pumping equipment is a key factor in ensuring that the concrete can be smoothly transported to the designated location. However, as the length of the delivery pipeline increases, the pressure that the pumping equipment needs to provide also increases accordingly. However, in the process of concrete pumping in super-high-rise projects, due to the long delivery pipeline, it is difficult to completely remove the air inside the pipeline, and bubbles or gaps are easily formed. These bubbles or gaps will not only affect the compactness and strength of the concrete, but also increase the resistance of pumping and reduce the pumping efficiency. In addition, in the pipeline cleaning link, due to the long delivery pipeline of the super-high-rise project, the cleaning difficulty is also increased accordingly. Especially when the intermittent construction period exceeds one week, the inner wall of the pipeline is prone to rust, further increasing the pumping resistance. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a super high-rise pumping pipeline lubricating mortar The super high-rise pumping pipeline lubricating mortar provided in this application adopts the following technical solution: A super high-rise pumping pipeline lubricating mortar, the components of which include, by weight, 400-450 parts of cement, 900-1000 parts of fine aggregate, 10-30 parts of regulator, 200-250 parts of water, 5-15 parts of admixture, 100-120 parts of fly ash and 50-70 parts of slag powder.

[0005] By adopting the above technical solutions, the high ratio of cement and fine aggregate ensures the strength and density of the mortar, which helps to lubricate the pipes without affecting the quality of the concrete. Fly ash and slag powder can not only fill the small gaps in the mortar, but also improve the workability of the mortar and further reduce the probability of bubble formation.

[0006] Optionally, the additive includes nano zinc oxide and ethylene-vinyl acetate copolymer.

[0007] By adopting the above technical solutions, nano zinc oxide improves the early and late strength of the mortar, enhances the overall performance of the mortar, and makes it more durable during pumping. The combined effect of nano zinc oxide and ethylene-vinyl acetate copolymer makes the mortar have better fluidity and lubricity, effectively reduces pumping resistance, and improves pumping efficiency.

[0008] Optionally, the preparation method of the ethylene-vinyl acetate copolymer is: Add 150-200 parts by weight of toluene and 60-100 parts of vinyl acetate monomer into a reaction kettle, and stir until completely dissolved; Add 5-10 parts of azobisisobutyronitrile into the reactor and seal it, introduce ethylene gas into the reactor, keep the pressure in the reactor between 10-30atm, the temperature at 50-70℃, and react for 2-4h; After the reaction is completed, carbon disulfide is added to stop the polymerization reaction, the reactor is cooled, and the reaction product is degassed, the solvent is recovered and dried to obtain pure ethylene-vinyl acetate copolymer.

[0009] Optionally, the regulator includes polyethylene glycol, sodium rosinate, and citric acid.

[0010] By adopting the above technical solution, the synergistic effect of polyethylene glycol and sodium rosin acid makes the mortar have better lubrication and fluidity, effectively reducing the pumping resistance, especially in long-distance pumping pipelines. The water retention property of polyethylene glycol ensures that the mortar still maintains appropriate moisture and adhesion during long-term pumping, preventing mortar separation and clogging. The retarding effect of citric acid extends the operation time of the mortar, improves the flexibility of pumping and the convenience of construction, and ensures that the mortar always maintains good workability during long-term pumping.

[0011] Optionally, the polyethylene glycol is graphene-modified polyethylene glycol, and the preparation method of the graphene-modified polyethylene glycol is: Add 40-60 parts of nanographene by weight to 180-200 parts of deionized water, add 1-5 parts of triethanolamine, and then add 120-160 parts of polyethylene glycol to the deionized water, and stir until completely dissolved to form a mixed solution; Add 5-15 parts of glutaraldehyde to the mixed solution, heat the mixed solution to 60-80° C., and continue stirring to react. After reacting for 6-8 hours, filter the reaction solution to collect the solid product, and wash and dry to obtain graphene-modified polyethylene glycol.

[0012] Optionally, after the reaction is completed, the pH value of the reaction solution is adjusted to 6-8.

[0013] Optionally, during the reaction, 20-30 parts of sodium dihydrogen phosphate need to be added to the reaction solution.

[0014] By adopting the above technical solutions, the introduction of nanographene significantly enhances the mechanical properties of the mortar, including compressive strength and tensile strength, ensuring the stability and durability of the mortar during high-pressure pumping. The lubricating effect of graphene-modified polyethylene glycol greatly improves the fluidity of the mortar and reduces pumping resistance, which is particularly suitable for long-distance and high-rise pumping. Sodium dihydrogen phosphate adheres to the inner wall of the pipe during mortar pumping to prevent rust and extend the service life of the pipe. Adjusting the pH value to 6-8 ensures the chemical stability of graphene-modified polyethylene glycol and avoids performance degradation caused by changes in the acid-base environment.

[0015] In the second aspect, the present application provides a method for preparing a super high-rise pumping pipeline lubricating mortar, which adopts the following technical solution: A method for preparing super high-rise pumping pipeline lubricating mortar comprises the following steps: Pour cement, fine aggregate, fly ash and slag powder, regulator and admixture into a mixer, start the mixer, and dry mix for 5-10 minutes to obtain a dry mix; Add water to the dry blend and mix for 15-20 minutes to form a uniform slurry.

[0016] By dry mixing for 5-10 minutes, various solid components can be fully and evenly distributed. Dry mixing helps to avoid local agglomeration or agglomeration after adding water, and improves the uniformity of the mortar. After adding water and stirring for 15-20 minutes, the components are further evenly mixed to form a homogeneous slurry. The extended stirring time allows the particles and liquid in the slurry to be fully mixed, forming good fluidity and workability, thereby improving the operability and construction effect during pumping.

[0017] In summary, this application has the following beneficial effects: 1. This application further improves the fluidity of the mortar by adjusting the water-cement ratio in the concrete mortar and using only fine aggregate instead of coarse aggregate, thereby lubricating the pipeline without affecting the quality of the concrete.

[0018] 2. In this application, nano zinc oxide is preferably used to improve the early and late strength of the mortar, enhance the overall performance of the mortar, and make it more durable during the pumping process. The combined effect of nano zinc oxide and ethylene-vinyl acetate copolymer makes the mortar have better fluidity and lubricity, effectively reduces pumping resistance, and improves pumping efficiency.

[0019] 3. The synergistic effect of polyethylene glycol and sodium rosin acid in this application significantly improves the lubricity and fluidity of the mortar, especially effectively reducing the resistance during long-distance pumping. The water-retaining property of polyethylene glycol ensures that the mortar maintains stable moisture and adhesion during long-term pumping, avoiding the separation and clogging of the mortar. DETAILED DESCRIPTION

[0020] The present application is further described in detail below in conjunction with the examples. It is particularly noted that if no specific conditions are specified in the following examples, the experiments are carried out according to conventional conditions or the conditions recommended by the manufacturer. Unless otherwise specified, the raw materials used in the following examples can be obtained from common commercial sources.

[0021] Preparation Example of Ethylene-Vinyl Acetate Copolymer Preparation Example 1 Preparation of ethylene-vinyl acetate copolymer: Clean the reactor to ensure it is free of water and impurities.

[0022] Weigh 50 kg of toluene and add it to the reactor, weigh 8 kg of vinyl acetate monomer and slowly add it to the toluene in the reactor. Start the agitator to ensure that the vinyl acetate monomer is completely dissolved in the toluene to form a uniform solution.

[0023] Weigh 0.8 kg of azobisisobutyronitrile and slowly add it into the reactor under stirring.

[0024] The reactor was sealed to ensure good airtightness, ethylene gas was introduced to maintain the pressure in the reactor at 20±1atm, the temperature in the reactor was adjusted to 60±5°C, the pressure and temperature in the reactor were maintained, and the polymerization reaction was carried out for 3 hours.

[0025] After the reaction time is over, add 0.5 kg of carbon disulfide into the reactor to terminate the polymerization reaction, and stir evenly to ensure that the reaction stops completely.

[0026] The reactor was cooled to room temperature, and the reaction product was passed through a degasser to remove the residual ethylene gas. The toluene solvent was recovered through a solvent recovery device. The residual solvent and impurities were removed by washing with ethanol, and the reaction product was low-temperature dried at 50°C. The dried product was pure ethylene-vinyl acetate copolymer.

[0027] Preparation Example 2 Preparation of ethylene-vinyl acetate copolymer: The difference from Preparation Example 1 is that 6 kg of vinyl acetate monomer is weighed and slowly added into the toluene in the reaction kettle.

[0028] Preparation Example 3 Preparation of ethylene-vinyl acetate copolymer: The difference from Preparation Example 1 is that 10 kg of vinyl acetate monomer is weighed and slowly added into the toluene in the reaction kettle.

[0029] Preparation Example 4 Preparation of ethylene-vinyl acetate copolymer: The difference from Preparation Example 1 is that ethylene gas is introduced to keep the pressure in the reactor at 5±1 atm.

[0030] Preparation Example 5 Preparation of ethylene-vinyl acetate copolymer: The difference from Preparation Example 1 is that ethylene gas is introduced to keep the pressure in the reactor at 35±1 atm.

[0031] Preparation example of graphene-modified polyethylene glycol Preparation Example 6 Preparation of graphene-modified polyethylene glycol: Clean the reactor to ensure it is free of water and impurities.

[0032] Weigh 20 kg of deionized water and add it to the reactor. Weigh 5 kg of nanographene and add it to the deionized water. Start the stirring device to evenly disperse the nanographene in the deionized water to form a uniform suspension.

[0033] Weigh 3 kg of triethanolamine and add it to the nanographene suspension. Stir continuously to ensure that the triethanolamine is evenly dispersed in the suspension.

[0034] Weigh 14 kg of polyethylene glycol and slowly add it to the suspension in the reactor, and continue stirring to completely dissolve the polyethylene glycol in the mixed solution to form a uniform mixed solution.

[0035] Weigh 1 kg of glutaraldehyde and slowly add it into the mixed solution.

[0036] The mixed solution in the reactor was heated to 70°C, kept at a constant temperature, and stirred for 7 hours to allow the reaction to proceed fully.

[0037] After the reaction time is over, the heating is stopped and the reactor is cooled to room temperature. The reaction solution is filtered and the solid product is collected, which is rinsed with ethanol and then dried at 50° C. to obtain dry graphene-modified polyethylene glycol.

[0038] Preparation Example 7 Preparation of graphene-modified polyethylene glycol: The difference from Preparation Example 6 is that 3 kg of nanographene is weighed and added into deionized water.

[0039] Preparation Example 8 Preparation of graphene-modified polyethylene glycol: The difference from Preparation Example 6 is that 7 kg of nanographene is weighed and added into deionized water.

[0040] Preparation Example 9 Preparation of graphene-modified polyethylene glycol: The difference from Preparation Example 6 is that the pH value of the reaction solution is adjusted to 7 after the reaction is completed.

[0041] Preparation Example 10 Preparation of graphene-modified polyethylene glycol: The difference from Preparation Example 6 is that 2.5 kg of sodium dihydrogen phosphate needs to be added to the reaction solution during the reaction. Example

[0042] Example 1 Preparation method of super high-rise pumping pipeline lubrication mortar: Pour 42kg 42.5R Portland cement, 95kg river sand with a particle size of 0.5-1.5mm, 11kg secondary fly ash with a purity of ≥98%, 6kg S95 slag powder, 20kg regulator and 10kg admixture into a mixer, start the mixer, and dry mix for 8 minutes to obtain a dry mix; 22 kg of water was added to the dry blend and mixed for 20 minutes to form a uniform slurry.

[0043] The additive contains 3.5 kg of nano zinc oxide and 6.5 kg of ethylene-vinyl acetate copolymer, and the ethylene-vinyl acetate copolymer is prepared by Preparation Example 1. The regulator contains 10 kg of polyethylene glycol, 7.5 kg of sodium rosinate, and 2.5 kg of citric acid.

[0044] Example 2 Preparation method of super high-rise pumping pipeline lubrication mortar: Pour 40kg 42.5R Portland cement, 95kg river sand with a particle size of 0.5-1.5mm, 10kg secondary fly ash with a purity of ≥98%, 5kg S95 slag powder, 20kg regulator and 10kg admixture into a mixer, start the mixer, and dry mix for 8 minutes to obtain a dry mix; 22 kg of water was added to the dry blend and mixed for 20 minutes to form a uniform slurry.

[0045] The additive contains 3.5 kg of nano zinc oxide and 6.5 kg of ethylene-vinyl acetate copolymer, and the ethylene-vinyl acetate copolymer is prepared by Preparation Example 1. The regulator contains 10 kg of polyethylene glycol, 7.5 kg of sodium rosinate, and 2.5 kg of citric acid.

[0046] Example 3 Preparation method of super high-rise pumping pipeline lubrication mortar: Pour 45kg 42.5R Portland cement, 95kg river sand with a particle size of 0.5-1.5mm, 12kg secondary fly ash with a purity of ≥98%, 7kg S95 slag powder, 20kg regulator and 10kg admixture into a mixer, start the mixer, and dry mix for 8 minutes to obtain a dry mix; 22 kg of water was added to the dry blend and mixed for 20 minutes to form a uniform slurry.

[0047] The additive contains 3.5 kg of nano zinc oxide and 6.5 kg of ethylene-vinyl acetate copolymer, and the ethylene-vinyl acetate copolymer is prepared by Preparation Example 1. The regulator contains 10 kg of polyethylene glycol, 7.5 kg of sodium rosinate, and 2.5 kg of citric acid.

[0048] Example 4 The preparation method of super high-rise pumping pipeline lubricating mortar is different from Example 1 in that the ethylene-vinyl acetate copolymer is prepared by Preparation Example 2.

[0049] Example 5 Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the ethylene-vinyl acetate copolymer is prepared by Preparation Example 3.

[0050] Example 6 Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the regulator contains 10 kg of graphene-modified polyethylene glycol, 7.5 kg of sodium rosin acid, and 2.5 kg of citric acid, and the graphene-modified polyethylene glycol is prepared by Preparation Example 6.

[0051] Example 7 Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the regulator contains 10 kg of graphene-modified polyethylene glycol, 7.5 kg of sodium rosin acid, and 2.5 kg of citric acid, and the graphene-modified polyethylene glycol is prepared by Preparation Example 9.

[0052] Example 8 Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the regulator contains 10 kg of graphene-modified polyethylene glycol, 7.5 kg of sodium rosin acid, and 2.5 kg of citric acid, and the graphene-modified polyethylene glycol is prepared by Preparation Example 10.

[0053] Comparative Example Comparative Example 1 Preparation method of super high-rise pumping pipeline lubricating mortar: Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the ethylene-vinyl acetate copolymer is prepared by Preparation Example 4.

[0054] Comparative Example 2 Preparation method of super high-rise pumping pipeline lubricating mortar: Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the ethylene-vinyl acetate copolymer is prepared by Preparation Example 5.

[0055] Comparative Example 3 Preparation method of super high-rise pumping pipeline lubricating mortar: Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the graphene-modified polyethylene glycol is prepared by Preparation Example 7.

[0056] Comparative Example 4 Preparation method of super high-rise pumping pipeline lubricating mortar: Preparation method of super high-rise pumping pipeline lubricating mortar: The difference from Example 1 is that the graphene-modified polyethylene glycol is prepared by Preparation Example 8.

[0057] Performance testing Detection Methods Slump test: Prepare a slump cone (height 300mm, bottom diameter 200mm, top diameter 100mm) and a measuring ruler.

[0058] Place the slump cone on a flat substrate, pour the lubricating mortar into the cone in three layers, and tamp each layer with a tamping rod. After filling, lift the cone upward to allow the mortar to collapse freely. Use a measuring ruler to measure the height difference before and after the mortar collapses, which is the slump value.

[0059] Pumping test: Take 2 m from Examples 1-8 and Comparative Examples 1-4 respectively 3 Lubricate the pipe with mortar and pour it into the hopper of the concrete pump. Start the pump and begin pumping the mortar through 10m*30cm internal non-corroded pipes. Keep the pump power constant and record the time when the pumping is completed. After the pumping is completed, place the pumping pipe under natural conditions for 15 days to observe its internal corrosion.

[0060] Table 1 Slump / cm Pumping time / min <![CDATA[Rust area / cm 2 > Example 1 20.3 8.3 13.6 Example 2 18.2 9.1 14.8 Example 3 21.8 8.8 14.2 Example 4 21.3 7.5 10.4 Example 5 20.1 7.8 10.8 Example 6 20.9 8.1 11.7 Example 7 21.7 7.4 10.2 Example 8 21.7 7.5 7.3 Comparative Example 1 16.5 10.8 15.5 Comparative Example 2 20.1 8.8 13.9 Comparative Example 3 15.2 11.6 18.6 Comparative Example 4 20.4 8.2 13.4 It can be seen from Example 1 and Comparative Examples 1-2 and Table 1 that too low a pressure in the ethylene-vinyl acetate copolymer reactor means that a small amount of ethylene gas is charged, which reduces the purity of the prepared ethylene-vinyl acetate copolymer. A higher ethylene concentration can accelerate the reaction rate, but too high a pressure may lead to an increase in side reactions.

[0061] From Example 1 and Comparative Examples 3-4 and Table 1, it can be seen that when the amount of graphene added is too much, the effect on the modified product is not obvious, while when the amount of graphene added is too little, the purity of the obtained graphene-modified polyethylene glycol is not high enough, and the effect of improving the lubrication and fluidity of the pipe lubricating mortar is not good.

[0062] It can be seen from Examples 1-3 and Table 1 that changing the addition ratio of the gelling material and the fine sand will affect the fluidity and pumping performance of the pipe lubricating mortar, among which the ratio in Example 1 is the best in this application.

[0063] It can be seen from Example 1 and Examples 4-8 and Table 1 that the addition of ethylene-vinyl acetate copolymer significantly improves the fluidity and pumping performance of the pipe lubricating mortar, among which the ethylene-vinyl acetate copolymer obtained in Preparation Example 1 has the best effect. The introduction of nanographene significantly enhances the mechanical properties of the mortar, including compressive strength and tensile strength, ensuring the stability and durability of the mortar during high-pressure pumping. The lubricating effect of graphene-modified polyethylene glycol greatly improves the fluidity of the mortar and reduces the pumping resistance, which is particularly suitable for long-distance and high-rise pumping. Sodium dihydrogen phosphate adheres to the inner wall of the pipe during the mortar pumping process to prevent rust and extend the service life of the pipe. Adjusting the pH value to 6-8 ensures the chemical stability of the graphene-modified polyethylene glycol and avoids performance degradation caused by changes in the acid-base environment.

[0064] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A super high-rise pumping pipeline lubricating mortar, characterized in that: The components include, by weight, 400-450 parts of cement, 900-1000 parts of fine aggregate, 10-30 parts of regulator, 200-250 parts of water, 5-15 parts of admixture, 100-120 parts of fly ash and 50-70 parts of slag powder.

2. The super high-rise pumping pipeline lubricating mortar according to claim 1 is characterized in that: The additives include nano zinc oxide and ethylene-vinyl acetate copolymer.

3. The super high-rise pumping pipeline lubricating mortar according to claim 2 is characterized in that: The preparation method of the ethylene-vinyl acetate copolymer is: Add 150-200 parts by weight of toluene and 60-100 parts of vinyl acetate monomer into a reaction kettle, and stir until completely dissolved; Add 5-10 parts of azobisisobutyronitrile into the reactor and seal it, introduce ethylene gas into the reactor, keep the pressure in the reactor between 10-30atm, the temperature at 50-70℃, and react for 2-4h; After the reaction is completed, carbon disulfide is added to stop the polymerization reaction, the reactor is cooled, and the reaction product is degassed, the solvent is recovered and dried to obtain pure ethylene-vinyl acetate copolymer.

4. The super high-rise pumping pipeline lubricating mortar according to claim 1 is characterized in that: The regulator includes polyethylene glycol, sodium rosinate and citric acid.

5. The super high-rise pumping pipeline lubricating mortar according to claim 4 is characterized in that: The polyethylene glycol is graphene-modified polyethylene glycol, and the preparation method of the graphene-modified polyethylene glycol is as follows: Add 40-60 parts of nanographene by weight to 180-200 parts of deionized water, add 1-5 parts of triethanolamine, and then add 120-160 parts of polyethylene glycol to the deionized water, and stir until completely dissolved to form a mixed solution; Add 5-15 parts of glutaraldehyde to the mixed solution, heat the mixed solution to 60-80° C., and continue stirring to react. After reacting for 6-8 hours, filter the reaction solution to collect the solid product, and wash and dry to obtain graphene-modified polyethylene glycol.

6. The super high-rise pumping pipeline lubricating mortar according to claim 5 is characterized by: After the reaction is completed, the pH value of the reaction solution is adjusted to 6-8.

7. The super high-rise pumping pipeline lubricating mortar according to claim 5 is characterized by: During the reaction, 20-30 parts of sodium dihydrogen phosphate need to be added to the reaction solution.

8. A method for preparing the super high-rise pumping pipeline lubricating mortar according to any one of claims 1 to 7, characterized in that: The following steps are involved: Pour cement, fine aggregate, fly ash and slag powder, regulator and admixture into a mixer, start the mixer, and dry mix for 5-10 minutes to obtain a dry mix; Add water to the dry blend and mix for 15-20 minutes to form a uniform slurry.