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CN-121974632-A - Synchronous grouting material, preparation method thereof and application thereof in submarine tunnel shield construction

CN121974632ACN 121974632 ACN121974632 ACN 121974632ACN-121974632-A

Abstract

The invention provides a synchronous grouting material, a preparation method thereof and application thereof in submarine tunnel shield construction, and belongs to the technical field of building materials. The material system comprises cementing materials, sand, mixing water and additives, wherein the cementing materials are composed of silicate cement clinker, calcined clay, limestone powder, nano silicon dioxide and calcium sulfate coagulation regulating components, the calcined clay and the limestone powder are compounded according to a certain mass ratio, and the nano silicon dioxide is introduced in the form of aqueous phase pre-dispersion suspension. Through the synergistic regulation and control of the LC3 composite gel system and the nano silicon dioxide, the slurry stability, pumpability and early bearing capacity can be improved while the clinker consumption is reduced, the long-term durability in the marine environment is improved, and the method is suitable for synchronous grouting in the shield construction of the submarine tunnel.

Inventors

  • LIU CHAO
  • MA LIKE
  • LIU HAI
  • He Junzuo
  • ZHAO ZHENYUN

Assignees

  • 广州大学

Dates

Publication Date
20260505
Application Date
20260209

Claims (10)

  1. 1. The synchronous grouting material is characterized by comprising the following components of cementing material, sand, mixing water and an additive; Wherein the mass ratio of the cementing material to the sand is 1:0.15-0.35; The mass ratio of the cementing material to the mixing water is 1:0.28-0.60; the mixing amount of the additive is 0.05-1.0% of the mass of the cementing material; the additive comprises a polycarboxylic acid water reducer.
  2. 2. The synchronous grouting material according to claim 1, wherein the cementing material comprises, by mass, 8-90% of silicate cement clinker, 6-58% of calcined clay, 3-29% of limestone powder, 0.5-2.5% of nano silicon dioxide and 0.3-4.5% of calcium sulfate setting component.
  3. 3. The synchronous grouting material according to claim 2, wherein the mass ratio of the calcined clay to the limestone powder is 1.5-2.5:1.
  4. 4. A synchronous grouting material according to claim 2 or 3, wherein the calcium sulphate set-regulating component comprises one or more of anhydrite, hemihydrate and anhydrite.
  5. 5. The synchronous grouting material of claim 2, wherein the average particle size of the nano silicon dioxide is 10-100 nm.
  6. 6. The synchronous grouting material of claim 1, wherein the cone time of the synchronous grouting material is 17-40 s.
  7. 7. The method for preparing the synchronous grouting material according to any one of claims 1 to 6, which is characterized by comprising the following steps: step 1), mixing silicate cement clinker, calcined clay, limestone powder and calcium sulfate setting components in proportion in a dry mode, adding sand, and continuously mixing in a dry mode to obtain a dry mixed material; Step 2), mixing nano silicon dioxide and mixing water, and then pre-dispersing to obtain nano silicon dioxide suspension; step 3), mixing the nano silicon dioxide suspension, the dry mixed material and the additive, and stirring to obtain the synchronous grouting slurry.
  8. 8. The method for preparing the synchronous grouting material according to claim 7, wherein in the step 2), the pre-dispersion is performed under an ultrasonic condition, the ultrasonic frequency is 20-60 kHz, and the pre-dispersion time is 10-40 min.
  9. 9. The method for preparing a synchronous grouting material according to claim 7 or 8, wherein in the step 3), the mixing comprises two stages of pre-stirring and stirring, wherein the rotational speed of the pre-stirring is 130-150 r/min, the time is 30-60 s, the stirring is high-speed stirring, the rotational speed of the high-speed stirring is 270-300 r/min, and the time is 2-6 min.
  10. 10. The use of the synchronous grouting material of any one of claims 1-6 in synchronous grouting for shield construction of submarine tunnels.

Description

Synchronous grouting material, preparation method thereof and application thereof in submarine tunnel shield construction Technical Field The invention relates to the technical field of building materials, in particular to a synchronous grouting material, a preparation method thereof and application thereof in submarine tunnel shield construction. Background Synchronous grouting is used for filling an annular gap between the shield segment and the stratum so as to support the surrounding stratum, control surface subsidence and inhibit groundwater infiltration. In submarine tunnel engineering, grouting materials are often subjected to severe requirements such as high external water pressure, chloride and sulfate ion attack, long-distance pumping requirements, rapid formation of bearing capacity after injection, and the like. The existing synchronous grouting material mostly uses ordinary silicate cement (Ordinary Portland Cement, OPC) as a main cementing material, and has the problems of large clinker consumption, high carbon emission and the like. Meanwhile, in the marine erosion environment, the long-term anti-permeability and anti-erosion performance of the marine anti-erosion composite material still has room for improvement. In addition, as the construction distance increases, the rheological stability of the slurry is more susceptible to temperature changes, raw material fluctuations and pumping shear, and bleeding, segregation or pipe plugging risks may occur, thereby affecting grouting plumpness and post-looping load bearing performance. The limestone calcined clay cement (Limestone CALCINED CLAY CEMENT, LC) adopts calcined clay and limestone powder to cooperatively replace part of clinker, so that the carbon emission can be obviously reduced. However, the LC3 system may have problems of slow early hydration, large water demand, sensitive rheology and stability in practical application, and it is difficult to simultaneously meet the comprehensive requirements of synchronous grouting for pumpability, low bleeding rate and early bearing capacity. The nano silicon dioxide can be used as crystal nucleus and active silicon source to promote early reaction and improve microstructure, but is easy to agglomerate and has poor dispersion stability. If the dispersion is insufficient or directly dry-blended, the water demand may be increased, the fluidity may be decreased, or the performance may be fluctuated. Therefore, it is necessary to develop an LC 3-based synchronous grouting material which is suitable for submarine tunnel conditions and has low carbon, environmental protection and construction adaptability, and provide an engineering preparation method thereof. Disclosure of Invention The invention aims to provide a synchronous grouting material, a preparation method thereof and application thereof in submarine tunnel shield construction, which are used for solving the technical problems of poor pumpability, higher bleeding and segregation risks, poor early bearing capacity and durability, high clinker consumption and large carbon emission of the synchronous grouting material for submarine tunnel shield construction in the prior art. In order to achieve the above object, the present invention provides the following technical solutions: the invention provides a synchronous grouting material which comprises cementing materials, sand, mixing water and an additive; Wherein the mass ratio of the cementing material to the sand is 1:0.15-0.35; The mass ratio of the cementing material to the mixing water is 1:0.28-0.60; the mixing amount of the additive is 0.05-1.0% of the mass of the cementing material; the additive comprises a polycarboxylic acid water reducer. Further, the cementing material comprises, by mass, 8-90% of silicate cement clinker, 6-58% of calcined clay, 3-29% of limestone powder, 0.5-2.5% of nano silicon dioxide and 0.3-4.5% of calcium sulfate setting regulating component. Further, the mass ratio of the calcined clay to the limestone powder is 1.5-2.5:1. Further, the calcium sulfate set-regulating component comprises one or more of dihydrate gypsum, semi-hydrated gypsum and anhydrous gypsum. Further, the average particle size of the nano silicon dioxide is 10-100 nm. Further, the cone flow time of the synchronous grouting material is 17-40 s. The invention provides a preparation method of the synchronous grouting material, which comprises the following steps: step 1), mixing silicate cement clinker, calcined clay, limestone powder and calcium sulfate setting components in proportion in a dry mode, adding sand, and continuously mixing in a dry mode to obtain a dry mixed material; Step 2), mixing nano silicon dioxide and mixing water, and then pre-dispersing to obtain nano silicon dioxide suspension; step 3), mixing the nano silicon dioxide suspension, the dry mixed material and the additive, and stirring to obtain the synchronous grouting slurry. Further, in the step 2), the pre-dispersing is per