Medium-heat lining concrete water cooling method based on maximum inner surface temperature difference age

文档序号:1321408 发布日期:2020-07-14 浏览:20次 中文

阅读说明:本技术 基于最大内表温差龄期的中热衬砌混凝土通水冷却方法 (Medium-heat lining concrete water cooling method based on maximum inner surface temperature difference age ) 是由 张润德 段亚辉 方朝阳 黎锦钊 张飞 李晓杰 张思盟 陈德尚 刘桂鑫 于 2019-07-17 设计创作,主要内容包括:本发明提供一种基于最大内表温差龄期的中热衬砌混凝土通水冷却方法,其特征在于包括:步骤1.收集衬砌结构中热水泥混凝土温控用资料;步骤2.计算衬砌结构中热水泥混凝土最大内表温差发生龄期d<Sub>Δtm</Sub>=-0.66×H+0.0004×C-0.0088×T<Sub>0</Sub>-0.0068×T<Sub>g</Sub>+5.02,H为衬砌结构中热水泥混凝土的厚度;C为衬砌结构中热水泥混凝土的强度等级;T<Sub>0</Sub>为衬砌结构中热水泥混凝土的浇筑温度;T<Sub>g</Sub>为通水冷却等效水温值,T<Sub>g</Sub>=35-T<Sub>w</Sub>,T<Sub>w</Sub>为通水冷却水温,步骤3.基于d<Sub>Δtm</Sub>确定通水冷却时间d<Sub>j</Sub>;步骤4.根据通水冷却时间d<Sub>j</Sub>进一步优化衬砌中热混凝土通水冷却措施,科学合理地实现温度裂缝。(The invention provides a medium-heat lining concrete water-feeding cooling method based on the age of the maximum inner surface temperature difference, which is characterized by comprising the following steps of: step 1, collecting data for temperature control of hot cement concrete in a lining structure; step 2, calculating the maximum inner surface temperature difference occurrence age d of the hot cement concrete in the lining structure Δtm =‑0.66×H+0.0004×C‑0.0088×T 0 ‑0.0068×T g +5.02, H is the thickness of the hot cement concrete in the lining structure; c is the strength grade of the hot cement concrete in the lining structure; t is 0 The pouring temperature of the hot cement concrete in the lining structure; t is g For cooling by passing water equivalent water temperature value, T g =35‑T w ,T w Cooling the water temperature by passing water, step 3. based on d Δtm Determining the cooling time d of water j (ii) a Step 4, cooling time d according to water j Further optimizing the water cooling measure of hot concrete in the lining, and scientifically and reasonably realizing temperature cracks.)

1. A middle-heat lining concrete water-feeding cooling method based on the age of the maximum inner surface temperature difference is characterized by comprising the following steps:

step 1, collecting data for temperature control of hot cement concrete in a lining structure;

step 2, calculating the maximum inner surface temperature difference occurrence age d of the hot cement concrete in the lining structureΔtm

dΔtm=-0.66×H+0.0004×C-0.0088×T0-0.0068×Tg+5.02,

In the above formula: h is the thickness of the hot cement concrete in the lining structure; c is the strength grade of the hot cement concrete in the lining structure; t is0The pouring temperature of the hot cement concrete in the lining structure; t isgFor cooling by passing water equivalent water temperature value, Tg=35-Tw,TwWater is introduced for cooling water;

step 3. based on dΔtmDetermining the cooling time d of waterj

Step 4, cooling time d according to waterjFurther optimizing the water cooling measure of hot concrete in the lining.

2. The mid-heat lining concrete water cooling method based on the age of the maximum internal surface temperature difference according to claim 1, characterized in that:

wherein, in step 2, when water cooling is not performed, T is takenw=35℃。

3. The mid-heat lining concrete water cooling method based on the age of the maximum internal surface temperature difference according to claim 1, characterized in that:

wherein, in step 3, dj=dΔtm+1。

4. The mid-heat lining concrete water cooling method based on the age of the maximum internal surface temperature difference according to claim 1, characterized in that:

wherein, the step 2 and the step 3 are executed by adopting a control processing device, and the occurrence age d of the maximum inner surface temperature difference of the hot cement concrete in the lining structure is calculatedΔtmAnd cooling time d by introducing waterj

5. The moderate heat lining concrete water cooling method based on the age of the maximum internal surface temperature difference according to claim 4, characterized in that:

wherein, the control processing device is also adopted to execute the step 4 according to the cooling time d of the waterjAnd controlling the water cooling system to cool the hot cement concrete in the brick structure by water.

Technical Field

The invention belongs to the technical field of concrete temperature control and crack prevention, and particularly relates to a middle-heat lining concrete water cooling method based on the maximum internal surface temperature difference age.

Background

Lining is a structure widely adopted in civil engineering. The lining concrete can be heated up due to the hydration heat of cementing materials such as cement and the like to generate very high internal temperature, for example, the highest temperature inside the lining concrete of a water delivery hole in a permanent ship lock of the three gorges hydro-junction reaches nearly 60 ℃, and the highest temperature inside the lining concrete of a hydropower station water delivery hole at the bottom of small waves reaches more than 70 ℃. The lining structure is small in thickness, high in strength mostly (such as the strength of a flood discharging tunnel of a large hydropower station reaches C50 and C60), high in internal temperature, large in temperature drop amplitude, high in temperature rise and temperature drop speed, and capable of generating temperature cracks easily in the construction period and being mostly penetrating harmful cracks due to the fact that the thin-wall lining is subjected to extremely strong constraints such as surrounding rocks and a supporting structure. The temperature difference is a root cause of temperature stress, and the larger the temperature difference, the larger the tensile stress generated, and the more likely the temperature crack is generated. The temperature difference includes a base temperature difference and an inner surface temperature difference. The maximum inner surface temperature difference occurs early, the early strength of the concrete is low, and temperature cracks are easy to generate in early temperature drop. Therefore, the maximum inner surface temperature difference occurrence age is also an important index for evaluating the temperature control cracking resistance of the concrete with the lining structure.

For example, as shown in fig. 1, the situation of early cracks of lining concrete of a flood discharging tunnel of a three-plate stream power station is shown, the treatment of the early cracks seriously affects the progress period and the construction cost of a project, and the failure of repairing perfect penetrating cracks (generally, the original concrete structure performance is difficult to achieve) seriously affects the durability and the service life of a lining structure, even causes leakage and threatens the safety of the project. The leakage of water (tunnel of Dong-deep water supply wild goose field) in the spraying state also directly endangers the health and comfort of people.

The occurrence age of the maximum internal surface temperature difference is not calculated and valued so far. Generally, when the finite element method is used for calculating and analyzing the temperature and the temperature stress, the occurrence age of the maximum inner surface temperature difference is briefly introduced.

Meanwhile, a cooling water pipe is buried in the concrete for water cooling, the highest temperature inside the structural concrete and the temperature difference inside the structural concrete can be effectively reduced, and the concrete is an effective temperature control and anti-cracking construction measure. The water cooling measures are adopted in the temperature control and crack prevention of the underground water conveying tunnel of the three gorges permanent ship lock, the temperature control and crack prevention of the underground water conveying tunnel lining of the three gorges permanent ship lock are researched as early as 1999, and the water cooling measures are adopted in the temperature control construction of the middle partition pier water conveying tunnel lining concrete, so that a good effect is obtained. Later, the construction method is adopted in the pressure-section lining concrete temperature control anti-cracking construction of the power generation cave of the three gorges right bank underground power station. Particularly, the concrete is comprehensively adopted in the concrete temperature control anti-cracking construction of underground engineering of hydropower stations such as Xiluodi, Baihe beach, Udongde and the like, and remarkable effect is achieved. Fig. 2 shows the cooling condition of the flood discharge tunnel lining concrete of the crane beach hydropower station by adopting the water cooling condition of the embedded water pipes.

However, the existing relevant design specifications generally lack clear and specific regulations for temperature control and water cooling of underground cavern engineering lining concrete, and the water cooling of the underground cavern lining concrete in the hydraulic and hydroelectric junction engineering is a method for referring to large-volume concrete water cooling of a dam. But the dam water-feeding cooling control indexes (stage, water-feeding time, temperature drop speed and the like) are not applicable. Therefore, the water cooling time of each project is different, the design of the white crane beach hydropower station requires that the water passing time is 15-30 d, the design of the Wudongde and Xiluodie hydropower stations requires 15d, and the design of the white crane beach hydropower station requires that the temperature reduction speed is less than 1.0 ℃/day. On one hand, the time of water cooling (the water cooling age is actually the water cooling age because only one time of water is passed and the water starts to be passed after the concrete is poured) has no scientific basis; secondly, the temperature drop speed of the lining concrete under the condition of no water cooling is mostly over 1.0 ℃/day, and the requirement is less than 1.0 ℃/day, which is obviously unreasonable. In addition, manual control is adopted in the process of water cooling, and the temperature control effect is related to the environmental influences of human responsibility, weather and the like.

The conditions are combined to show that the maximum internal surface temperature difference generating age is an important index for evaluating the temperature control anti-cracking performance of the lining structure, but a calculation method is still unavailable so far, a water cooling measure for effectively reducing the maximum temperature and the internal surface temperature difference inside the structural concrete is adopted, and the water cooling time is not scientifically determined.

Disclosure of Invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for cooling moderate heat lining concrete by water based on the age of maximum internal temperature difference, which can obtain the age of maximum internal temperature difference of the moderate heat lining concrete in a lining structure, and based on the age, cool moderate heat lining concrete in a lining structure by water, thereby scientifically and reasonably realizing temperature cracks.

In order to achieve the purpose, the invention adopts the following scheme:

as shown in FIG. 3, the invention provides a method for cooling medium-heat lining concrete by water based on the age of the maximum inner surface temperature difference, which is characterized by comprising the following steps:

step 1, collecting data for temperature control of hot cement concrete in a lining structure;

step 2, calculating the maximum inner surface temperature difference occurrence age d of the hot cement concrete in the lining structureΔtm

dΔtm=-0.66×H+0.0004×C-0.0088×T0-0.0068×Tg+5.02 (equation 1), with the unit: day;

in the above formula: h is the thickness (m) of the hot cement concrete in the lining structure; c is the strength grade (MPa) of the hot cement concrete in the lining structure; t is0The pouring temperature (DEG C) of the hot cement concrete in the lining structure is shown; t isgIs the equivalent water temperature value (DEG C) of water cooling, Tg=35-Tw,TwThe temperature (DEG C) of cooling water is introduced;

step 3. based on dΔtmDetermining the cooling time d of waterj

Step 4, cooling time d according to waterjFurther optimizing the water cooling measure of hot concrete in the lining.

Preferably, the method for cooling the medium-heat lining concrete based on the age of the maximum internal surface temperature difference provided by the invention by water can also have the following characteristics: in step 2, when water cooling is not performed, T is takenw=35℃。

Preferably, the method for cooling the medium-heat lining concrete based on the age of the maximum internal surface temperature difference provided by the invention by water can also have the following characteristics: in step 3, dj=dΔtm+1 (equation 2), with the unit: and (5) day. Get dj=dΔtmAnd +1, the temperature control and cracking prevention method is determined according to a large number of finite element method simulation calculations and field water cooling temperature control tests, so that the value can be taken to effectively reduce the highest temperature and the maximum inner surface temperature difference in the concrete, ensure that the internal temperature of the concrete can not rise again, and realize the temperature control and cracking prevention target at the optimal time.

Preferably, the method for cooling the medium-heat lining concrete based on the age of the maximum internal surface temperature difference provided by the invention by water can also have the following characteristics: executing the step 2 and the step 3 by adopting a control processing device, and calculating the occurrence age d of the maximum inner surface temperature difference of the hot cement concrete in the lining structureΔtmAnd cooling time d by introducing waterj

Preferably, the method for cooling the medium-heat lining concrete based on the age of the maximum internal surface temperature difference provided by the invention by water can also have the following characteristics: step 4 is also executed by adopting a control processing device, and water cooling is carried out according to the water feedingBut time djAnd controlling the water cooling system to cool the hot cement concrete in the building structure through water, so as to realize temperature control and crack prevention. The water cooling system should be laid and installed in advance on the hot cement concrete in the lining structure. The water cooling pipes in the water cooling system are arranged in a snake shape from bottom to top, and the arrangement density of the central area is properly increased.

In addition, the calculation of the maximum inner surface temperature difference occurrence age d of the hot cement concrete in the lining proposed in the step 2ΔtmFormula 1 is taken as an example of the lining of the hot cement concrete in the creeper giant hydropower station flood discharge tunnel, power generation tunnel and diversion tunnel projects, 78 schemes such as different section forms and sizes, different lining thicknesses, different strength grades, different pouring temperatures, different water-through cooling water temperatures and the like are simulated and calculated by adopting a three-dimensional finite element method, the maximum internal surface temperature difference occurrence age of the hot cement concrete is obtained (see table 1 below), and then the data are creatively analyzed and researched to obtain the hot cement concrete lining.

TABLE 1 age of occurrence of maximum internal surface temperature difference of hot cement concrete in the linings of flood discharge tunnel, power generation tunnel and diversion tunnel of Xiluo river hydropower station

Action and Effect of the invention

The intermediate heat lining concrete water cooling method based on the maximum inner surface temperature difference age provided by the invention has the advantages that:

(1) can be suitable for any lining structure (comprising different civil engineering types, different structural forms, different thicknesses, different strengths and the like), carries out calculation of the maximum inner surface temperature difference generating age of hot concrete in lining and analysis of the early temperature rise and temperature drop characteristics,

(2) the method is scientific. Occurrence age d of maximum inner surface temperature difference of moderate heat cement concrete in liningΔtmAnd the calculation formula comprehensively reflects the influence of main parameters such as the thickness, the strength grade, the pouring temperature, the water cooling and the water temperature of the hot cement concrete structure in the lining.

(3) Calculating the recommended water cooling time d of the moderate heat cement lining concrete according to a formulajThe temperature control and anti-cracking lining concrete is reasonable in optimization, the temperature inside the lining concrete can not rise, and temperature control and anti-cracking can be effectively achieved.

Drawings

Fig. 1 is a diagram of a crack of a flood discharging tunnel of a three-plate stream power station related to the background art, wherein (a) is an overall diagram, and (b) is a partially enlarged diagram;

FIG. 2 is a layout view of concrete water-through cooling water pipes lined on the side wall of a flood discharge tunnel of a white crane beach hydropower station in the background art;

FIG. 3 is a flow chart of a method for cooling the medium-heat lining concrete through water based on the age of the maximum internal temperature difference, which is involved in the embodiment of the invention;

FIG. 4 is a sectional view of a 1.0m thick lining concrete structure of a brook ferry spillway tunnel according to an embodiment of the present invention;

fig. 5 is a graph of representative point temperatures of a central cross section of a thermally lined concrete side wall of 1.0m thickness in a brook ferry spillway tunnel according to an embodiment of the present invention.

Detailed Description

The concrete implementation of the middle-heat lining concrete water cooling method based on the maximum inner surface temperature difference age according to the invention is explained in detail below by taking the hot concrete in the lining structure of the flood discharge tunnel engineering of the Xiluou hydropower station as an example in combination with the attached drawings.

< basic data of hot concrete in lining structure of flood discharging tunnel of Xiluoda hydropower station >

Characteristics of the river luo du hydropower station flood discharge energy dissipation: high head, large discharge, narrow river valley, high flood discharge power, which is the most important term in the world of arch dam hubs. According to the requirements of the total current discharge capacity of a junction, the topographic and geological conditions, the hydrological characteristics and the reservoir dispatching operation mode of a dam site area, and the diversion in the middle and later construction periods, the flood discharge and energy dissipation building is formed by 7 surface holes and 8 deep holes in a dam body, and a plunge pool is arranged behind the dam; the left and right sides of the bank are respectively provided with 2 flood discharging tunnels with pressure-joint non-pressure tunnels.

The pressure hole consists of a straight section and a bent section, the hole diameter is 15.0m, the turning radius of the bent section is 200m, the central angle is 62 degrees, the tail end is a round-to-square pressure slope connecting section, the length of the pressure slope connecting section is 25.00m, the circular hole with the height of 15m is gradually changed to 12m × 14m, and then the circular hole is connected with an arc-shaped working gate chamber.

The non-pressure tunnel section is formed from upper straight slope section, Woqi curve section, slope connecting section, reverse arc curve section and lower straight slope section, etc. its non-pressure tunnel section size is 14m × 19m (width is × height), its section form is circular arch straight wall type, and its surrounding rock type is identical to pressure section, and its surrounding rock is II and III1、Ⅲ2And IV, excavating surrounding rocks of II types, wherein the excavation width is 15.70m, the height is 20.65m, and the lining thickness is 0.85 m; III1Class of surrounding rock: the excavation width is 16.20m, the height is 21.10m, and the lining thickness is 1.0 m; III2Class of surrounding rock: the excavation width is 16.20m, the height is 21.10m, and the lining thickness is 1.0 m; class IV surrounding rock: the excavation width is 17.20m, the height is 22.10m, and the lining thickness is 1.5 m. Since the report mainly studies the crack mechanism, the cause and the influence of various factors, taking the XW3 section as an example, the flood discharging tunnel 1.0m thick lining concrete structure is shown in fig. 4.

< example one >1.0m thick (F2 type) lining

Taking a lining with the thickness of 1.0m (F2 type) as an example, simulation calculation is carried out by adopting a finite element method. The calculation conditions are as follows: pouring in 7 months and 1 day, wherein the pouring temperature is 27 ℃, water cooling and temperature control measures are not adopted, and side walls adopt C90Concrete with normal state of 40 and C for top arch25Pumping concrete, only researching the side wall and the top arch, not considering pouring of the bottom plate, opening and pouring for 3 days, then removing the formwork, wherein the interval period of pouring the side wall and the top arch is 31 days, and the length of the parting seam is 9 m.

The maximum temperature and the maximum internal temperature difference of a typical part of a 1.0m thick (F2 type) lining concrete side wall and the occurrence time thereof are shown in Table 2 below, and the temperature duration curve is shown in FIG. 5.

TABLE 2 side wall center section representative point maximum temperature and time of occurrence

As shown in fig. 3, the method for cooling the medium-heat lining concrete by water based on the age of the maximum internal temperature difference provided by the embodiment comprises the following steps:

step 1, collecting data for temperature control of hot cement concrete in a lining structure, comprising:

step 1-1, the basic data of the lining structure engineering are arranged and analyzed. The basic data of the flood discharging hole of the brook ferry hydropower station are as described above. The simulation calculation results of the temperature control finite element method for the hot cement concrete in the lining with the thickness of 1.0m (F2 type) are shown in the table 1. As the flood discharge tunnel is a level 1 building, the water flow speed is as high as 50m/s, and the temperature control and crack prevention of the lining concrete are very important.

Step 1-2, analyzing the technical requirements of temperature control design of lining concrete. According to the engineering data of the Xiluoda hydropower station, concrete is lined in the flood discharge hole, pouring temperature needs to be controlled, and temperature control measures need to be taken.

Step 2, calculating the maximum inner surface temperature difference occurrence age d of the hot cement concrete in the lining structureΔtm

According to the above information, H is 1.0 m; the moderate heat cement C is 40 MPa; t is0Cooling at 27 deg.C without water, and taking Tw=35℃,Tg0 ℃. Calculated by substituting into equation 1Δtm=4.14(d)。

Step 3, calculating and determining the cooling time d of the hot cement concrete in the lining structurej

Based on dΔtmCalculating the cooling time d of water by the formula 2j=dΔtm+1 ═ 4.14+1 ═ 5.14 (d). It is recommended that the cooling time of the moderate heat cement concrete is 6 days.

Step 4, cooling time d according to waterjFurther optimizing lining medium-heat concrete water-through cooling measure

Hot cement concrete in a 1.0m thick (F2 type) lining structure of a flood discharging tunnel of a Xiluodian hydropower station is adopted, and water cooling time is 10-15 days in actual engineering construction. The water cooling time is determined by calculation of formula 2 to be 5.14d, and the water cooling time can be 6 d. Therefore, the water cooling time can be further optimized to 6d, the water cooling time can be obviously shortened, and the engineering construction cost is saved.

And (3) comparison and analysis:

according to the second calculation result in the table 2, the maximum inner surface temperature difference occurrence age of the concrete is calculated by a finite element method to be 4d, and the value d is calculated by the formula 1 of the invention methodΔtmThe error is only 3.4% and the precision is high as 4.14(d) and 0.15d earlier. The actual water cooling time of the project is 10-15 d, the water cooling time is determined by calculation of a formula 2 and is 5.14d, the water cooling time can be further optimized to 6d, and the project construction cost is saved.

< example II > moderate heat cement concrete in xi luo dug spillway tunnel lining structure with thickness of 0.8m and 1.5m

For analyzing the applicability of formula 1 for lining thickness and water cooling, for the cross section of the lining structure shown in FIG. 4, the size of the cross section after lining is kept unchanged, only the thickness of the lining is changed to 0.8m and 1.5m, firstly, finite element method simulation calculation is adopted, and then, the maximum inner surface temperature difference generation age d is carried out by adopting the formula 1ΔtmAnd (5) calculating and analyzing.

Finite element simulation calculation, wherein the calculation scheme under the condition of water cooling is as follows: pouring is started in 7 months and 1 day in summer, the bottom plate and the side top arch are poured separately, and the pouring interval period is 31 days; pouring at 18 ℃, the distance between water pipes is 1.0m, introducing water, cooling for 15d at 15 ℃, removing the mold after 3 days, and sprinkling water on the surface for maintenance for 28 days after mold removal. Taking lining thickness of 0.8m and 1.5m respectively to perform simulation calculation, and settling the highest temperature TmaxMaximum inner surface temperature difference △ TmaxAnd their age of occurrence are listed in table 3 below.

TABLE 3 concrete highest temperature T of side wall with different lining thicknessmaxMaximum inner surface temperature difference △ TmaxAnd its age (water cooling)

In actual engineering construction, the water cooling time is 10-15 d.

As shown in fig. 3, the method for calculating the maximum inner surface temperature difference and the water cooling age of the medium-heat lining concrete provided by the embodiment includes the following steps:

step 1, collecting data for temperature control of hot cement concrete in a lining structure, comprising:

and (5) arranging and analyzing basic data of the lining structure engineering and analyzing the technical requirements of the lining concrete temperature control design.

Step 2, calculating the maximum inner surface temperature difference occurrence age d of the hot cement concrete in the lining structureΔtm

According to the above data, H is 0.8m, 1.5 m; c is 40 MPa; t is0The temperature is 18 ℃; cooling with 15 deg.C water, collecting Tw=15℃,Tg20 ℃ is set; cooling without water, and taking Tw=35℃,Tg0 ℃. The results of the calculation substituting equation 1 are shown in table 4 below.

TABLE 4 occurrence age d of the maximum internal surface temperature difference of the lining concreteΔtmAnd comparison with the calculated value of the finite element method

Step 3, calculating and determining the cooling time d of the hot cement concrete in the lining structurej

Based on dΔtmCalculating d of lining thickness H0.8 m, 1.5m by formula 2jThe times, listed in Table 4, above. It is recommended that the cooling time of the medium heat cement concrete with lining thickness H0.8 m and 1.5m is 6 days.

Step 4, cooling time d according to waterjFurther optimizing lining medium-heat concrete water-through cooling measure

The thickness H of the flood discharging tunnel of the Xiluodian hydropower station is 0.8m and 1.5m, and the hot cement concrete is used in a lining structure, and the water cooling time is 10-15 days in actual engineering construction. The water cooling time is 5.22d and 5.68d determined by calculation of formula 2, and the water cooling time can be 6 d. Therefore, the water cooling time can be further optimized to 6d, the water cooling time can be obviously shortened, and the engineering construction cost is saved.

And (3) comparison and analysis:

calculation according to Table 4 aboveAchievement, calculating the highest temperature occurrence age by the finite element method and calculating the value d by the formula 1ΔtmAnd the error is small, and the engineering construction requirement can be met. Particularly, the recommended value of the water cooling time is shorter than the actually adopted value of the construction, and the method is more economical.

The side wall lining concrete of the flood discharging hole of the Xiluou hydropower station has no phenomenon of internal temperature rising after water cooling is finished, the operation has been carried out for many years, the scheme is adopted to carry out temperature control anti-cracking, so that the temperature crack generation period is 'possible' in winter, no crack is generated, and the remarkable temperature control anti-cracking effect is obtained.

The results of the above examples show that the method of the invention can be applied to any lining structure (including different civil engineering types, different structural forms, different thicknesses, different strengths and the like) to calculate the maximum internal surface temperature difference generating age of lining concrete and analyze the early temperature rise and temperature drop characteristics.

The method is scientific. Occurrence age d of maximum inner surface temperature difference of lining concreteΔtmThe calculation formula 1 comprehensively reflects the influence of main parameters such as the thickness, the strength grade, the pouring temperature, the water cooling and the water temperature of the lining concrete structure.

Calculating the recommended water cooling time d of the moderate heat cement lining concrete according to the formula 2jThe temperature control and anti-cracking lining concrete is reasonable in optimization, the temperature inside the lining concrete can not rise, and temperature control and anti-cracking can be effectively achieved.

The above embodiments are merely illustrative of the technical solutions of the present invention. The method for cooling the water in the medium thermal lining concrete based on the age of the maximum inner temperature difference is not limited to the contents described in the above embodiments, but is subject to the scope defined by the claims. Any modification or supplement or equivalent replacement made by a person skilled in the art on the basis of this embodiment is within the scope of the invention as claimed in the claims.

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