WO2022116526A1

WO2022116526A1 - Expansion grout for prestressed pipeline grouting and preparation method therefor

Info

Publication number: WO2022116526A1
Application number: PCT/CN2021/103331
Authority: WO
Inventors: 王辉诚; 刘康; 孙作晓; 裴新意; 刘军; 闫敏; 王勇; 纪红灿; 邓晓阳; 王利业; 李峰; 张健
Original assignee: 中广核工程有限公司; 中国建筑第二工程局有限公司
Priority date: 2020-12-02
Filing date: 2021-06-29
Publication date: 2022-06-09
Also published as: CN112608095A

Abstract

Provided are expansion grout for prestressed pipeline grouting and a preparation method therefor. The method comprises: adding water at a suitable temperature into a primary stirrer, adding cement into the primary stirrer after adding the water at the suitable temperature, and completing primary stirring of cement paste by using a primary stirring method; after primary stirring, leaving same to stand for a preset time period; and after leaving same to stand for the preset time period, adding an expanding agent into a secondary stirrer, performing secondary stirring on grout by using a secondary stirring method, and obtaining expansion grout after secondary stirring. The prepared expansion grout has a low fluidity loss over time, stable grout rheology, a low bleeding rate and stable grout performance, a grout preparing and grouting period can be effectively shortened, and an available expansion rate of the grout is improved; and the adverse influences of early-stage false solidification of cement on the fluidity of the grout are reduced.

Description

Expansion grout for prestressed pipeline grouting and preparation method thereof

technical field

The invention relates to the technical field of building materials, and more particularly, to an expansion slurry for prestressed pipeline grouting and a preparation method thereof.

Background technique

In a nuclear power plant, the reactor-type nuclear island containment is a double-shell structure. The inner containment, as the third safety barrier of the nuclear power plant reactor building, is a prestressed reinforced concrete structure with vertical steel bundles, horizontal steel bundles and Gamma steel bundles. The prestressed construction of the containment adopts the post-tensioning method. The prestressed tunnel grouting after the prestressing tension is the key factor for the quality assurance of the prestressed construction, and it is also one of the key guarantee factors for the stability of the stress state under the long-term action of the prestressed system. .

The containment in the nuclear island of the nuclear power plant adopts the post-tensioning prestressing system. After the concrete construction of the inner containment is completed, the steel strands are threaded and tensioned in the reserved prestressed pipeline, and then the cement paddle is used for pressure injection in the pipeline. Dense, to protect the steel strand from being eroded by the outside world.

The traditional method for preparing the expansion slurry in the prestressed pipeline is to put cement, water and expansion agent into the mixer at one time, and complete the mixing at one time. Therefore, the construction time of the current slurry is too short to meet the requirements of prestressed pipeline injection.

technical problem

The technical problem to be solved by the present invention is to provide an expansion slurry for prestressed pipeline grouting and a preparation method thereof, aiming at the above-mentioned defects of the prior art.

technical solutions

The technical solution adopted by the present invention to solve the technical problem is: constructing a preparation method of expansion slurry for prestressed pipeline grouting, including:

Take suitable temperature water and add it to the primary mixer, add cement to the primary mixer under the condition of adding the suitable temperature water, and use the primary stirring method to complete the primary stirring of the cement slurry;

After completing one stirring, let it stand for a preset period of time;

After standing for a preset period of time, an expansion agent is added to the secondary mixer, and the slurry is agitated a second time by a secondary stirring method, and after the secondary stirring is completed, an expansion slurry is obtained.

Preferably, under the condition that the suitable temperature water is added, adding cement to the primary mixer includes:

Take 291~309kg of cement;

Under the condition of adding the suitable temperature water, add the 291-309kg cement to the primary mixer while stirring.

Preferably, the one-time mixing method to complete the one-time mixing of the cement slurry includes:

After the cement is completely added to the primary mixer, the cement slurry is agitated at the first mixing time and at the first mixing speed, and when the mixing time reaches the first mixing time, the primary mixing of the cement slurry is completed.

Preferably, the first stirring time is: 2 to 4 minutes;

The first stirring speed is: 1500-2200 rpm.

Preferably, the preset time period is: 30-120 minutes.

Preferably, after standing for a preset period of time, adding an expansion agent to the secondary mixer includes:

After standing for a preset period of time, add the bulking agent to the secondary mixer in one go.

Preferably, adding the expansion agent to the secondary mixer at one time after standing for a preset period of time includes:

Take 3.528~3.672kg expansion agent;

After standing for a preset period of time, the 3.528-3.672 kg expansion agent was added to the secondary mixer at one time.

Preferably, the adding of suitable temperature water to the primary mixer includes:

Take 91.5~97.5kg of warm water;

Add 91.5~97.5kg of suitable temperature water into the mixer once.

Preferably, the suitable temperature water is adding a preset weight of ice to a preset weight of normal temperature water, and after mixing the ice and water, the water temperature is between 1-7°C.

Preferably, the cement is Portland cement.

Preferably, the cement is Portland cement of grade 42.5.

Preferably, the bulking agent is Sika bulking agent.

Preferably, the secondary stirring of the slurry by the secondary stirring method includes:

After adding the expansion agent to the secondary mixer, the slurry is stirred according to the second stirring time and the second stirring speed;

After the stirring time reaches the second stirring time, the secondary stirring of the slurry is completed to obtain an expanded slurry.

Preferably, the second stirring time is 2 to 5 minutes;

The second stirring speed is: 1700-2500 rpm.

Preferably, the method further includes:

During the standing process, transfer the cement slurry that has completed the primary mixing to the secondary mixer;

After the preset time period is reached, the cement slurry that has completed the primary mixing is added to the secondary mixer;

The expansion agent was added to the secondary mixer equipped with the cement slurry that completed the primary mixing.

Preferably, the expansion slurry consists of the following raw materials by weight:

Suitable temperature water: 91.5~97.5kg;

Cement: 291~309kg;

Expansion agent: 3.528~3.672kg.

Preferably, the cement, the suitable temperature water and the expansion agent are combined and obtained by the following mass ratios:

Cement: moderate temperature water: expansion agent = 1: 0.33: 0.013.

Cement: moderate temperature water: expansion agent = 1: 0.315: 0.012.

Preferably, including:

Get 99kg of suitable temperature water and add it into the primary mixer, under the condition of adding 99kg of suitable temperature water, add 300kg of cement to the primary mixer and stir; and after adding 300kg of cement, use 1500 ~ 2200 rpm stirring Stir at speed for 4 minutes;

After completing one stirring, let stand for 45 minutes;

After standing for 45 minutes, 3.9 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.

Preferably, including:

Get 99kg of suitable temperature water and add it to the primary mixer, under the condition that 99kg of suitable temperature water is added, add 300kg of cement to the primary mixer and stir; Stir at speed for 4 minutes;

After completing one stirring, let stand for 75 minutes;

After standing for 75 minutes, 3.9 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.

Preferably, including:

After completing one stirring, let stand for 105 minutes;

After standing for 105 minutes, 3.9 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.

Preferably, including:

Get 94.5kg of suitable temperature water and add it to the primary mixer, and under the condition that 94.5kg of suitable temperature water is added, add 300kg of cement to the primary mixer and stir; and after adding 300kg of cement, use 1500~2200 rpm stirring speed for 4 minutes;

After completing one stirring, let it stand for 30 minutes;

After standing for 30 minutes, 3.6 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.

Preferably, the power of the primary mixer is greater than the power of the secondary mixer.

The present invention also provides an expansion slurry for prestressed pipeline grouting, wherein the expansion slurry is prepared by the above-mentioned preparation method of an expansion slurry for prestressed pipeline grouting.

Suitable temperature water: 91.5~97.5kg;

Cement: 291~309kg;

Expansion agent: 3.528~3.672kg.

Cement: moderate temperature water: expansion agent = 1: 0.33: 0.013.

Cement: moderate temperature water: expansion agent = 1: 0.315: 0.012.

Preferably, the performance requirements of the expansion grout for prestressed pipeline grouting are:

Mobility: 14s < Mobility < 26s;

Slurry temperature: Slurry temperature < 25°C.

beneficial effect

Implementing the expansion slurry for prestressed pipeline grouting and the preparation method thereof of the present invention has the following beneficial effects: comprising: taking suitable temperature water and adding it into the primary mixer, adding cement to the primary mixer under the condition of adding the suitable temperature water, and using a primary mixer The stirring method completes one stirring of the cement slurry; after completing the first stirring, let it stand for a preset period of time; after standing for a preset period of time, add an expansion agent to the secondary mixer, and use the secondary stirring method to carry out the slurry. Secondary stirring, after the secondary stirring is completed, an expanded slurry is obtained. The swelling slurry prepared by the invention has little loss of fluidity with time, stable slurry rheology, small bleeding rate, stable slurry performance, can effectively shorten the pulping-grouting period, improve the available expansion ratio of the slurry, and reduce the early stage of cement. Adverse effects of false coagulation on slurry fluidity.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, in which:

FIG. 1 is a schematic flow chart of the preparation method of the expansion slurry for prestressed pipeline grouting according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

In order to have a clearer understanding of the technical features, objects and effects of the present invention, the specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

Referring to FIG. 1 , FIG. 1 is a schematic flowchart of an optional embodiment of each embodiment of a method for preparing expansion slurry for prestressed pipe grouting provided by the present invention.

As shown in Figure 1, the preparation method of the expansion slurry for prestressed pipeline grouting includes:

Step S1, take suitable temperature water and add it to the primary mixer, under the condition that the suitable temperature water is added, add cement to the primary mixer, and use the primary stirring method to complete the primary stirring of the cement slurry.

In the embodiment of the present invention, the suitable temperature water is adding a preset weight of ice to a preset weight of normal temperature water, and after mixing the ice and water, the preset water temperature range is: 1~7°C.

In the embodiment of the present invention, adding suitable temperature water to the primary mixer includes: taking 91.5-97.5 kg of suitable temperature water; adding 91.5-97.5 kg of suitable temperature water to the primary mixer. Under the condition of adding suitable temperature water, adding cement to the primary mixer includes: taking 291~309kg of cement; under the condition of adding suitable temperature water, adding 291~309kg of cement to the primary mixer while stirring. Among them, the feeding speed should be slow and uniform when adding cement to the primary mixer.

Further, in the embodiment of the present invention, using the one-time stirring method to complete the one-time stirring of the cement slurry includes: after the cement is completely added to the one-time mixer, stirring the cement slurry once according to the first stirring time and the first stirring speed, and After the stirring time reaches the first stirring time, one stirring of the cement slurry is completed.

Optionally, the first stirring time is: 2-4 minutes; the first stirring speed is: 1500-2200 rpm.

Step S2, after completing one stirring, let it stand for a preset period of time.

In this embodiment of the present invention, optionally, the preset time period is 30 to 120 minutes.

Step S3: After standing for a preset period of time, add an expansion agent to the secondary mixer, use a secondary stirring method to agitate the slurry a second time, and obtain an expansion slurry after the secondary stirring is completed.

Wherein, adding the expansion agent to the secondary mixer after standing for a preset period of time includes: adding the expansion agent to the secondary mixer at one time after standing for a preset period of time.

Further, in some embodiments, after standing for a preset period of time, adding the expansion agent to the secondary mixer at one time includes: taking 3.528-3.672 kg of expansion agent; after standing for a preset period of time, adding the expansion agent at one time to the secondary mixer 3.528~3.672kg expansion agent is added to the secondary mixer.

Further, in some embodiments, the secondary stirring of the slurry by the secondary stirring method includes: after adding the expansion agent to the secondary mixer, stirring the slurry according to the second stirring time and the second stirring speed; After the stirring time reaches the second stirring time, the secondary stirring of the slurry is completed to obtain an expanded slurry.

Optionally, the second stirring time is 2-5 minutes; the second stirring speed is: 1700-2500 rpm.

Further, in some embodiments, the preparation method of the expansion slurry for prestressed pipeline grouting further includes: during the standing process, transferring the cement slurry that has completed primary stirring to a secondary mixer; after reaching a preset time period , add the cement slurry that has completed the primary stirring into the secondary mixer; add the expansion agent to the secondary mixer equipped with the cement slurry that has completed the primary stirring.

Optionally, in some embodiments, the cement is Portland cement. For example, 42.5 grade Portland cement can be used. Further, in some embodiments, the bulking agent is a Sika bulking agent.

Further, the swelling slurry prepared in the embodiment of the present invention is made up of the following raw materials by weight:

Suitable temperature water: 91.5~97.5kg;

Cement: 291~309kg;

Expansion agent: 3.528~3.672kg.

In some embodiments, cement, moderate temperature water and expansion agent are combined in the following mass ratio: cement: moderate temperature water: expansion agent=1:0.33:0.013.

Alternatively, in some other embodiments, the cement, the suitable temperature water and the expansion agent are combined in the following mass ratios: cement: suitable temperature water: expansion agent=1:0.315:0.012.

Described below with specific embodiments:

Example 1:

Cement, suitable temperature water and expansion agent are combined according to the following mass ratios: cement: suitable temperature water: expansion agent=1:0.33:0.013.

Among them, suitable temperature water: 99kg, cement: 300kg, expansion agent: 3.9kg.

Let stand for 45 minutes.

In this embodiment, the preparation method of the expansion slurry for prestressed pipeline grouting specifically includes:

Step S101, get 99kg of suitable temperature water and add it into the primary mixer, under the condition of adding 99kg of suitable temperature water, add 300kg of cement into the primary mixer and stir; and after adding 300kg of cement, adopt a stirring speed of 2000 rev/min Stir for 4 minutes;

Step S102, after completing one stirring, let stand for 45 minutes;

Step S103, after standing for 45 minutes, add 3.9 kg of expansion agent, and stir for 2 minutes at a stirring speed of 2200 rpm.

In step 103, after the secondary stirring is completed, the expansion slurry that can be used for grouting the prestressed pipeline can be obtained.

Further, after the completion of step S103, sampling and measurement of the prepared slurry of the expanded slurry is performed. After measurement, the test data of the expansion slurry prepared in Example 1 can be obtained as follows:

Rheological properties, including:

Slurry temperature: 15.1℃;

Out of the machine mobility: 17.5s;

3h expansion rate: 4.1%;

3h bleeding rate: 1.8%;

Physical properties of hardened pastes, including:

28d flexural strength: 10.0MPa;

28d compressive strength: 66.9MPa;

Dry density: 1840kg/m ³ ;

Capillary water absorption: 0.4;

28d shrinkage value: 1450μm/m;

Porosity: 31.0%.

Among them, the performance requirements of the expansion slurry for prestressed pipeline grouting are: fluidity: 14s < fluidity < 26s; slurry temperature: slurry temperature < 25 ℃.

It can be seen from the above test data that the fluidity of the expanded slurry prepared in this example is 17.5s, and in the range of 14s~26s, the slurry temperature is 15.1°C, less than 25°C. It can be seen from this that the expansion slurry prepared in this example completely meets the performance requirements of the expansion slurry for prestressed pipeline grouting.

Embodiment 2:

Let stand for 75 minutes.

Step S201, get 99kg of suitable temperature water and add it to the primary mixer, under the condition of adding 99kg of suitable temperature water, add 300kg of cement into the primary mixer and stir; and after adding 300kg of cement, adopt a stirring speed of 2000 rev/min Stir for 4 minutes.

Step S202, after completing one stirring, let it stand for 75 minutes.

Step S203, after standing for 75 minutes, add 3.9 kg of expansion agent, and stir for 2 minutes at a stirring speed of 2200 rpm.

In step S203, after the secondary stirring is completed, the expansion slurry that can be used for grouting the prestressed pipeline can be obtained.

Further, after the completion of step S203, sampling and measurement of the prepared slurry of the expanded slurry is performed. After measurement, the test data of the expansion slurry prepared in Example 1 can be obtained as follows:

Rheological properties, including:

Slurry temperature: 16.7℃;

Liquidity out of the machine: 16.0s;

3h expansion rate: 4.2%;

3h bleeding rate: 1.8%;

Physical properties of hardened pastes, including:

28d flexural strength: 10.0MPa;

28d compressive strength: 64.8MPa;

Dry density: 1830kg/m ³ ;

Capillary water absorption: 0.4;

28d shrinkage value: 1490μm/m;

Porosity: 31.0%.

It can be seen from the above test data that the fluidity of the expanded slurry prepared in this example is 16s, and in the range of 14s~26s, the slurry temperature is 16.7°C, less than 25°C. It can be seen from this that the expansion slurry prepared in this example completely meets the performance requirements of the expansion slurry for prestressed pipeline grouting.

Embodiment three:

Let stand for 105 minutes.

Step S301, get 99kg of suitable temperature water and add it to the primary mixer, under the condition of adding 99kg of suitable temperature water, add 300kg of cement into the primary mixer and stir; and after adding 300kg of cement, adopt a stirring speed of 2000 rev/min Stir for 4 minutes.

Step S302, after completing one stirring, let it stand for 105 minutes.

Step S303, after standing for 105 minutes, add 3.9 kg of expansion agent, and stir for 2 minutes at a stirring speed of 2200 rpm.

In step S303, after the secondary stirring is completed, the expansion slurry that can be used for grouting the prestressed pipeline can be obtained.

Further, after the completion of step S303, sampling measurement is performed on the prepared slurry of the expanded slurry. After measurement, the test data of the expansion slurry prepared in Example 1 can be obtained as follows:

Rheological properties, including:

Slurry temperature: 19.0℃;

Liquidity out of the machine: 14.0s;

3h expansion rate: 4.3%;

3h bleeding rate: 1.8%;

Physical properties of hardened pastes, including:

28d flexural strength: 9.5MPa;

28d compressive strength: 60.2MPa;

Dry density: 1810kg/m3;

Capillary water absorption: 0.4;

28d shrinkage value: 1490μm/m;

Porosity: 31.0%.

It can be seen from the above test data that the fluidity of the expanded slurry prepared in this example is 14.0s, and in the range of 14s~26s, the slurry temperature is 19.0°C, less than 25°C. It can be seen from this that the expansion slurry prepared in this example completely meets the performance requirements of the expansion slurry for prestressed pipeline grouting.

Embodiment 4:

Cement, suitable temperature water and expansion agent were combined according to the following mass ratios: cement: suitable temperature water: expansion agent = 1: 0.315: 0.012.

Among them, suitable temperature water: 94.5kg, cement: 300kg, expansion agent: 3.6kg.

Rest: 30 minutes.

Step S401, get 94.5kg of suitable temperature water and add it to the primary mixer, and under the condition of adding 94.5kg of suitable temperature water, add 300kg of cement to the primary mixer while stirring; and after adding 300kg of cement, use 2000 rpm Stirring speed for 4 minutes;

Step S402, after completing one stirring, let stand for 30 minutes;

Step S403, after standing for 30 minutes, add 3.6 kg of expansion agent, and stir for 2 minutes at a stirring speed of 2200 rpm.

Further, the power of the primary mixer in the embodiment of the present invention is greater than the power of the secondary mixer.

The expansion slurry prepared by the preparation method of the expansion slurry for prestressed pipeline grouting in the embodiment of the present invention has less fluidity loss with time, stable slurry rheology, low bleeding rate and stable slurry performance.

Further, the present invention divides the preparation of the expansion slurry into two steps. First, a high-power mixer is used to stir the cement and water to prepare a non-expandable cement slurry; After adding the expansion agent to the slurry, it is stirred in a low-power mixer, and the grouting is followed by the secondary stirring according to the grouting needs, which can effectively shorten the grouting-grouting cycle and improve the available expansion rate of the slurry; moreover, after the secondary stirring of the cement slurry, Reduce the adverse effect of early false setting of cement on slurry fluidity.

The present invention also provides an expansion slurry for prestressed pipeline grouting, wherein the expansion slurry can be prepared by the preparation method of the expansion slurry for prestressed pipeline grouting disclosed in the embodiment of the present invention.

Optionally, the expansion slurry consists of the following raw materials by weight:

Suitable temperature water: 91.5~97.5kg;

Cement: 291~309kg;

Expansion agent: 3.528~3.672kg.

Further, in some embodiments, cement, suitable temperature water and expansion agent are combined in the following mass ratios: cement: suitable temperature water: expansion agent=1:0.33:0.013.

Or, in some other embodiments, the cement, the suitable temperature water and the expansion agent are combined according to the following mass ratio: cement: suitable temperature water: expansion agent=1:0.315:0.012.

The above embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement accordingly, and cannot limit the protection scope of the present invention. All equivalent changes and modifications made with the scope of the claims of the present invention shall fall within the scope of the claims of the present invention.

Claims

A preparation method of expansion slurry for prestressed pipeline grouting, characterized in that, comprising:

Take suitable temperature water and add it to the primary mixer, under the condition of adding the suitable temperature water, add cement to the primary mixer, and adopt the primary stirring method to complete the primary stirring of the cement slurry;

After completing one stirring, let it stand for a preset period of time;

After standing for a preset period of time, an expansion agent is added to the secondary mixer, and the slurry is stirred for a second time by a secondary stirring method. After the secondary stirring is completed, an expansion slurry is obtained.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the adding cement to the primary mixer under the condition of adding the suitable temperature water comprises:

Take 291~309kg of cement;

Under the condition of adding the suitable temperature water, add the 291-309kg cement to the primary mixer while stirring.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 2, wherein the one-time stirring method to complete the one-time stirring of the cement slurry comprises:

After the cement is completely added to the primary mixer, the cement slurry is agitated at the first mixing time and at the first mixing speed, and when the mixing time reaches the first mixing time, the primary mixing of the cement slurry is completed.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 3, wherein the first stirring time is 2 to 4 minutes;

The first stirring speed is: 1500-2200 rpm.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the preset time period is 30 to 120 minutes.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the adding expansion agent to the secondary mixer after standing for a preset period of time comprises:

After standing for a preset period of time, add the bulking agent to the secondary mixer in one go.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 6, wherein the step of adding the expansion agent to the secondary mixer at one time after standing for a preset period of time comprises:

Take 3.528~3.672kg expansion agent;

After standing for a preset period of time, the 3.528-3.672 kg expansion agent was added to the secondary mixer at one time.
The preparation method of the expansion slurry for prestressed pipeline grouting according to claim 1, wherein the step of adding suitable temperature water to the primary mixer comprises:

Take 91.5~97.5kg of warm water;

Add 91.5~97.5kg of suitable temperature water into the mixer once.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the temperature-appropriate water is the addition of a preset weight of ice to a preset weight of normal temperature water, and after the ice and water are mixed, the water temperature drops to 1 -7°C.
The method for preparing expansion slurry for prestressed pipeline grouting according to any one of claims 1-9, wherein the cement is Portland cement.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 10, wherein the cement is Portland cement of grade 42.5.
The method for preparing expansion slurry for prestressed pipeline grouting according to any one of claims 1-9, wherein the expansion agent is a Sika expansion agent.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the secondary stirring of the slurry by a secondary stirring method comprises:

After the expansion agent is added to the secondary mixer, the slurry is stirred according to the second stirring time and the second stirring speed;

After the stirring time reaches the second stirring time, the secondary stirring of the slurry is completed to obtain an expanded slurry.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 13, wherein the second stirring time is 2 to 5 minutes;

The second stirring speed is: 1700-2500 rpm.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the method further comprises:

During the standing process, transfer the cement slurry that has completed the primary mixing to the secondary mixer;

After the preset time period is reached, the cement slurry that has completed the primary mixing is added to the secondary mixer;

The expansion agent was added to the secondary mixer equipped with the cement slurry that completed the primary mixing.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 1, wherein the expansion slurry is composed of the following raw materials by weight:

Suitable temperature water: 91.5~97.5kg;

Cement: 291~309kg;

Expansion agent: 3.528~3.672kg.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 1, wherein the cement, the suitable temperature water and the expansion agent are combined and obtained by the following mass ratios:

Cement: moderate temperature water: expansion agent = 1: 0.33: 0.013.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 1, wherein the cement, the suitable temperature water and the expansion agent are combined and obtained by the following mass ratios:

Cement: moderate temperature water: expansion agent = 1: 0.315: 0.012.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 17, characterized in that, comprising:

Take 99kg of suitable temperature water and add it to the primary mixer, add 300kg of cement to the primary mixer and stir while adding 99kg of suitable temperature water; and after adding 300kg of cement, use Stir at a stirring speed of 1500~2200 rpm for 4 minutes;

After completing one stirring, let stand for 45 minutes;

After standing for 45 minutes, 3.9 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 17, characterized in that, comprising:

Take 99kg of suitable temperature water and add it to the primary mixer, add 300kg of cement to the primary mixer and stir while adding 99kg of suitable temperature water; and after adding 300kg of cement, use Stir at a stirring speed of 1500~2200 rpm for 4 minutes;

After completing one stirring, let stand for 75 minutes;

After standing for 75 minutes, 3.9 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 17, characterized in that, comprising:

Take 99kg of suitable temperature water and add it to the primary mixer, add 300kg of cement to the primary mixer and stir while adding 99kg of suitable temperature water; and after adding 300kg of cement, use Stir at a stirring speed of 1500~2200 rpm for 4 minutes;

After completing one stirring, let stand for 105 minutes;

After standing for 105 minutes, 3.9 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.
The preparation method of expansion slurry for prestressed pipeline grouting according to claim 18, characterized in that, comprising:

Take 94.5kg of suitable temperature water and add it to the primary mixer, and under the condition that 94.5kg of suitable temperature water is added, add 300kg of cement to the primary mixer while stirring; and after adding 300kg of cement, use 1500~2200 rpm stirring speed for 4 minutes;

After completing one stirring, let it stand for 30 minutes;

After standing for 30 minutes, 3.6 kg of expansion agent was added, and the mixture was stirred at a stirring speed of 1700-2500 rpm for 2 minutes.
The method for preparing expansion slurry for prestressed pipeline grouting according to claim 1, wherein the power of the primary mixer is greater than the power of the secondary mixer.
An expansion slurry for prestressed pipeline grouting, characterized in that the expansion slurry is prepared by the preparation method of the expansion slurry for prestressed pipeline grouting according to any one of claims 1-23.
The expansion slurry for prestressed pipeline grouting according to claim 24, wherein the expansion slurry is composed of the following raw materials by weight:

Suitable temperature water: 91.5~97.5kg;

Cement: 291~309kg;

Expansion agent: 3.528~3.672kg.
The expansion slurry for prestressed pipeline grouting according to claim 24, wherein the cement, the suitable temperature water and the expansion agent are combined and obtained according to the following mass ratios:

Cement: moderate temperature water: expansion agent = 1: 0.33: 0.013.
The expansion slurry for prestressed pipeline grouting according to claim 24, wherein the cement, the suitable temperature water and the expansion agent are combined and obtained according to the following mass ratios:

Cement: moderate temperature water: expansion agent = 1: 0.315: 0.012.
The expansion slurry for prestressed pipeline grouting according to claim 24, wherein the performance requirements of the expansion slurry for prestressed pipeline grouting are:

Mobility: 14s < Mobility < 26s;

Slurry temperature: Slurry temperature < 25°C.