CN110263490B - Concrete dam temporary surface stress analysis method - Google Patents
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Abstract
The invention provides a concrete dam temporary face stress analysis method, which relates to the technical field of hydraulic and hydroelectric engineering, and comprises the following steps: determining a preset heat preservation state of the surface of the dam body; determining a surface heat dissipation coefficient; calculating a concrete temperature field according to the surface heat dissipation coefficient, and simulating and calculating temperature stress generated by temperature difference according to the concrete temperature field; the method for analyzing the temporary surface stress of the concrete dam body provided by the invention can be used for solving the technical problem that the construction of the thermal insulation state of the dam body surface lacks reasonable basis in the prior art.
Description
Technical Field
The invention relates to the technical field of water conservancy and hydropower engineering, in particular to a method for analyzing temporary surface stress of a concrete dam body.
Background
Cracks generated due to local temperature differences are common quality problems of concrete dams, and conventional temperature control anti-cracking methods comprise: and (5) reducing pouring temperature, cooling by water, preserving heat on the surface and the like. Therefore, the heat preservation state of the concrete surface has a larger influence on the cracking condition of the dam body surface, however, due to reasons of warehouse preparation and the like, heat preservation measures in the construction intermittence period of the dam body warehouse surface poured in winter are inevitably uncovered, and in order to reduce the production cost, the dam body surface is stressed to use low-cost heat preservation facilities, so that the problem of cracking of the dam body surface is caused by environmental cooling during the cold and damp. Because of lack of reasonable planning of heat preservation state, when concrete dam body is under construction, adopt the mode of carrying out heat preservation preliminary treatment at the dam body surface generally, when the dam body surface appears the fracture and then strengthen heat preservation measure, there is great trial and error cost in the construction period from this, and has influenced dam body construction quality because of dam body surface fracture.
Disclosure of Invention
The invention aims to provide a method for analyzing temporary surface stress of a concrete dam body, which aims to solve the technical problem that the construction of the surface heat preservation state of the dam body in the prior art lacks reasonable basis.
In a first aspect, the method for analyzing the temporary surface stress of the concrete dam body provided by the invention comprises the following steps: determining a preset heat preservation state of the surface of the dam body; determining a surface heat dissipation coefficient; calculating a concrete temperature field according to the surface heat dissipation coefficient, and simulating and calculating temperature stress generated by temperature difference according to the concrete temperature field; judging the safety condition of the dam body, and adjusting the thermal insulation measure of the surface of the dam body.
With reference to the first aspect, the present invention provides a first possible implementation manner of the first aspect, where the step of determining a preset thermal insulation state of a dam surface includes: according to the surface state of the dam body, the surface of the dam body is divided into the following categories: GK (Gate Bipolar transistor) 1 : paving a heat preservation quilt in a wet state; GK (Gate Bipolar transistor) 2 : poor paving of the heat preservation quilt; GK (Gate Bipolar transistor) 3 : laying a heat preservation quilt with accumulated water at the lower part; the surface of the dam body is free of heat preservation quilt.
With reference to the first possible implementation manner of the first aspect, the present invention provides a second possible implementation manner of the first aspect, wherein, under a condition that the surface of the dam body is not provided with a heat preservation quilt, whether the wind speed of the surface of the dam body is greater than a preset wind speed is detected; if the wind speed of the dam surface is less than or equal to the preset wind speed, the type of the dam surface is GK 4 : the first type is a state without heat preservation quilt; if the wind speed of the dam surface is larger than the preset wind speed, the type of the dam surface is GK 5 : the second type is a state without heat preservation quilt.
With reference to the first aspect, the present invention provides a third possible implementation manner of the first aspect, wherein the concrete dam temporary face stress analysis method further includes: detecting environmental information with preset time as an interval, wherein the environmental information comprises temperature data and dam surface wind speed; the preset time is 2-5 min.
With reference to the first aspect, the present invention provides a fourth possible implementation manner of the first aspect, wherein the step of determining a surface heat dissipation coefficient includes: preset value beta of preset surface heat dissipation coefficient 0 Simulating and measuring the initial calculation temperature of the test point; the first error value is calculated according to the following formula,
wherein T is eer(1) The first error value is given in degrees celsius; n is the total number of steps of time divided in the calculation process; k (K) b(i0) Is the surface heat dissipation coefficient beta 0 Under the condition, the time step is the calculated temperature of the measuring point in the step i, and the unit is the temperature; k (K) c(i) Is time ofThe actual temperature of the measuring point in the step i is measured in degrees centigrade; calculating the mth surface heat dissipation coefficient beta according to the following formula m ＝β 0 +Δβ· (m-1), where β m For the mth surface heat dissipation coefficient, delta beta is a preset increment value, and m is more than or equal to 2; calculating the mth calculated temperature of the test point through simulation and calculation, and calculating the mth error value according to the following formula>
Wherein K is b(im) Is the surface heat dissipation coefficient beta m Under the condition, the time step is the calculated temperature of the measuring point in the step i; up to T eer(m) <T eer(m+1) Then the surface heat dissipation coefficient β=β m 。
With reference to the first aspect, the present invention provides a fifth possible implementation manner of the first aspect, wherein the step of determining a surface heat dissipation coefficient includes: when the dam surface is not provided with the heat preservation quilt, the surface heat dissipation coefficient is calculated according to the following formula, wherein beta=523.2+324.72v a Wherein v is a The wind speed is the unit m/s of the surface of the dam body.
With reference to the second possible implementation manner of the first aspect, the present invention provides a sixth possible implementation manner of the first aspect, wherein the step of determining a safety condition of the dam includes: according to the formula
Calculating the safety coefficient K of the dam body f Wherein sigma is the sum of temperature stress generated by various temperature differences, and the unit is MPa; epsilon p The concrete limit pull-up value is set; e (E) c The elastic modulus of the concrete is expressed in MPa.
With reference to the sixth possible implementation manner of the first aspect, the present invention provides a seventh possible implementation manner of the first aspect, wherein if K f <1.5, paving a heat preservation quilt in a wet state on the surface of the dam body, and increasing the layer number of the heat preservation quilt; if K f And the surface of the dam body is not provided with a heat preservation quilt, and the dam body is judged to be free of cracking risk.
In combination with the sixth possible implementation of the first aspectEmbodiments the present invention provides an eighth possible embodiment of the first aspect, wherein, if K f(q) Not less than 1.5 and K f(q+1) <1.5, configuring the dam surface state as GK q The method comprises the steps of carrying out a first treatment on the surface of the Wherein q is the type number of the dam surface state, GK q For the surface state of the dam with the number of q, K f(q) The safety coefficient corresponding to the surface state of the q-th dam body.
With reference to the sixth possible implementation manner of the first aspect, the present invention provides a ninth possible implementation manner of the first aspect, wherein the concrete dam temporary surface stress analysis method further includes: calculating the temperature stress during the cold weather according to the predicted cold weather simulation; calculating the safety coefficient K of the dam body according to the temperature stress f The method comprises the steps of carrying out a first treatment on the surface of the If the safety factor K f And if the temperature is less than 1.5, issuing early warning and enhancing the heat preservation of the dam body.
The embodiment of the invention has the following beneficial effects: the method comprises the steps of determining a preset heat preservation state of the surface of a dam body, determining a surface heat dissipation coefficient, calculating a concrete temperature field according to the surface heat dissipation coefficient, simulating temperature stress generated by calculating a temperature difference according to the concrete temperature field, judging the safety condition of the dam body, adjusting heat preservation measures of the surface of the dam body, measuring and calculating the heat dissipation coefficient of the surface of the dam body according to preset heat preservation setting, calculating the temperature stress generated by the temperature difference, evaluating the risk of cracking of the dam body in the preset heat preservation state, learning the installation condition of the dam body, reasonably adjusting the heat preservation measures of the surface of the dam body according to the safety condition of the dam body, strengthening heat preservation without cracking of the surface of the dam body, and avoiding excessive heat preservation to generate higher cost.
In order to make the above objects, features and advantages of the present invention more comprehensible, preferred embodiments accompanied with figures are described in detail below.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the related art, the drawings that are required to be used in the description of the embodiments or the related art will be briefly described, and it is apparent that the drawings in the description below are some embodiments of the present invention, and other drawings may be obtained according to the drawings without inventive effort for those skilled in the art.
Fig. 1 is a schematic flow chart of a method for analyzing temporary surface stress of a concrete dam according to an embodiment of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Physical quantities in the formulas, unless otherwise noted, are understood to be basic quantities of basic units of the international system of units, or derived quantities derived from the basic quantities by mathematical operations such as multiplication, division, differentiation, or integration.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Example 1
As shown in fig. 1, the method for analyzing the temporary surface stress of the concrete dam body provided by the embodiment of the invention comprises the following steps: determining a preset heat preservation state of the surface of the dam body; determining a surface heat dissipation coefficient; calculating a concrete temperature field according to the surface heat dissipation coefficient, and simulating and calculating temperature stress generated by temperature difference according to the concrete temperature field; judging the safety condition of the dam body, and adjusting the thermal insulation measure of the surface of the dam body.
Specifically, the air temperature data, solar radiation data and dam information data are automatically collected on site, and the data are transmitted to a server. Under the condition of a preset heat preservation state, simulating and measuring the heat dissipation coefficient of the surface of the dam body by adopting a finite element analysis method, calculating the stress of the surface of the dam body according to the heat dissipation coefficient of the surface, and drawing a dam body surface stress prediction curve. And judging the safety condition of the surface of the dam body according to the surface stress and the allowable tensile strength of the concrete, or determining the corresponding safety coefficient according to the surface stress of the dam body, so as to divide the safety level of the dam body, and adjusting the heat preservation measure of the surface of the dam body according to the safety condition of the surface of the dam body. For example, if the dam body has a cracking risk, reinforcing heat preservation measures of the dam body, and performing the calculation until the surface of the dam body reaches a safe state; if the dam surface has no cracking risk, weakening the current heat preservation measures, carrying out the calculation, and adopting the heat preservation measures with lower cost under the condition that the dam surface has no cracking risk, thereby reducing the construction cost.
In the embodiment of the invention, the step of determining the preset heat preservation state of the surface of the dam body comprises the following steps: according to the surface state of the dam body, the surface of the dam body is divided into the following categories: GK (Gate Bipolar transistor) 1 : paving a heat preservation quilt in a wet state; GK (Gate Bipolar transistor) 2 : poor paving of the heat preservation quilt; GK (Gate Bipolar transistor) 3 : laying a heat preservation quilt with accumulated water at the lower part; the surface of the dam body is free of heat preservation quilt. Wherein GK 1 Has better heat preservation effect than GK 2 ，GK 2 Has better heat preservation effect than GK 3 The method comprises the steps of carrying out a first treatment on the surface of the At GK 1 On the basis of the above, the heat preservation effect can be further improved by increasing the layer number of the heat preservation quilt; when the heat preservation quilt is in bad lap joint, the heat preservation quilt is damaged or the heat preservation quilt is adjacent to each otherIn the case of the pitch, the insulation cover may be considered to be laid poorly.
Further, under the condition that the surface of the dam body is not provided with a heat preservation quilt, detecting whether the wind speed of the surface of the dam body is larger than a preset wind speed; if the wind speed of the surface of the dam body is less than or equal to the preset wind speed, the type of the surface of the dam body is GK 4 : the first type is a state without heat preservation quilt; if the wind speed of the surface of the dam body is larger than the preset wind speed, the type of the surface of the dam body is GK 5 : the second type is a state without heat preservation quilt. Wherein the preset wind speed can be set to be 4-5 m/s, and the preset wind speed is set to be 4m/s for example, when the wind speed of the surface of the dam body is greater than 4m/s, the condition that the heat preservation quilt is not present and the wind is strong is judged, namely the surface state of the dam body is judged to be GK 5 : the second type is a state without heat preservation quilt. When the wind speed of the surface of the dam body is less than or equal to 4m/s, judging that the dam body is not provided with a heat preservation quilt and is breeze or windless, namely judging that the surface state of the dam body is GK 4 : the first type is a state without heat preservation quilt.
Further, the method for analyzing the temporary surface stress of the concrete dam body further comprises the following steps: detecting environmental information with preset time as an interval, wherein the environmental information comprises temperature data and dam surface wind speed; the preset time is 2-5 min. The environmental information also comprises solar radiation data acquired by the microclimate instrument, the microclimate instrument can be arranged at an upstream cofferdam, the air temperature data and the solar radiation data can be called at a frequency of 3 min/time to be used as a basis for predicting the surface temperature of the dam, namely, the surface temperature of the dam approaches to the surface air temperature of the dam, and a temperature field curve is drawn according to the white surface temperature.
Further, the method for analyzing the temporary surface stress of the concrete dam body further comprises the following steps: performing finite element grid division on the surface of the dam body, wherein the grid division step comprises the following steps: performing grid division by taking a blank layer poured in a certain period as an analysis object; wherein, the mesh size ratio along the transverse river direction is 0.1:0.9:2:7:7:2:0.9:0.1; the mesh size ratio in the along river direction is 1:2:8:8:2:1, a step of; the height of six height layers is selected, the dimension of the latest pouring layer in the height direction is 0.1m, and the dimensions of the rest pouring layers in the height direction are 0.5m. And the temperature of the dam body and the corresponding stress are calculated by adopting finite element analysis, and the temperature inside the dam body can be determined by adopting a finite element analysis or inversion calculation mode and is compared with measured data to realize verification.
Further, for GK 1 : paving a heat preservation quilt in a wet state, GK 2 : poor paving of heat preservation quilt and GK 3 : the three states of the heat preservation quilt with water accumulation at the lower part are laid, and inversion analysis can be performed by adopting the following steps: monitoring the condition of a thermometer in the heat-preserving quilt; the method comprises the steps of obtaining the internal information of the dam management system by calling the internal information of the dam management system: dam casting temperature, dam size information, dam casting time, air temperature information, wind speed information and solar radiation information faced by the dam; adopting finite element calculation, and realizing temperature field finite element calculation according to the following formula after discrete programming:
boundary conditions: />
Wherein (1)>
Representing partial differential operation, τ is time(s), λ is thermal conductivity, α is thermal conductivity, θ is adiabatic temperature rise, +.>
For the first type of boundary condition temperature, e is the given heat flow at the boundary, beta is the heat release coefficient at the boundary, T a Is the ambient temperature in the case of natural convection.
The step of determining the surface heat dissipation factor comprises: preset value beta of preset surface heat dissipation coefficient 0 Simulating and measuring the initial calculation temperature of the test point; the first error value is calculated according to the following formula,
wherein T is eer(1) The first error value is given in degrees celsius; n is a meterCalculating the total step number of divided time in the process; k (K) b(i0) Is the surface heat dissipation coefficient beta 0 Under the condition, the time step is the calculated temperature of the measuring point in the step i, and the unit is the temperature; k (K) c(i) The actual temperature of the measuring point is measured when the time step is the step i, and the unit is the temperature; calculating the mth surface heat dissipation coefficient beta according to the following formula m ＝β 0 +Δβ (m-1), where β m For the mth surface heat dissipation coefficient, delta beta is a preset increment value, and m is more than or equal to 2; calculating the mth calculated temperature of the test point through simulation and calculation, and calculating the mth error value according to the following formula>
Wherein K is b(im) Is the surface heat dissipation coefficient beta m Under the condition, the time step is the calculated temperature of the measuring point in the step i; up to T eer(m) <T eer(m+1) Then the surface heat dissipation coefficient β=β m . For example: preset value beta of preset surface heat dissipation coefficient 0 Is 100 kJ/(m) 2 h.DEG C), wherein Deltaβ is a preset increment value selected to be 30 kJ/(m) 2 H· deg.c), the calculated surface heat dissipation coefficient is β=100+30 (m-1) kJ/(m) 2 ·h·℃)。
Further, the step of determining the surface heat dissipation factor includes: when the surface of the dam body is not provided with the heat preservation quilt, the heat dissipation coefficient of the surface is calculated according to the following formula, wherein beta=523.2+324.72v a Wherein v is a The wind speed is the unit m/s of the surface of the dam body.
Further, the step of calculating the dam surface stress includes: solving by an incremental method, and dividing the time tau into a series of time periods: Δτ 1 、Δτ 2 ......Δτ n In the period Deltaτ n The internally generated strain increase is:
wherein: />
Is an elastic strain increment; />
Is creep strain increment; />
Is the temperature strain increment; />
Is the autogenous volume deformation increment; />
Is the dry shrinkage strain increment. And (3) adopting a finite element method to integrate the whole units, so as to obtain a whole balance equation:
[K]{Δδ n }＝{ΔP n } L +{ΔP n } C +{ΔP n } T +{ΔP n } 0 +{ΔP n } S wherein: [ K ]]Is an overall stiffness matrix; { ΔP n } L The node load increment caused by external load is adopted; { ΔP n } C The node load increment caused by creep is adopted; { ΔP n } T The node load increment caused by temperature is adopted; { ΔP n } 0 The node load increment caused by autogenous volume deformation is adopted; { ΔP n } S Is the node load increment caused by the shrinkage. Find the displacement increment delta of each node n After } according to Δσ n ＝[D][B]{Δδ n Calculation of the stress delta sigma n Wherein [ B ]]For displacement strain matrix, [ D ]]For the stress-strain matrix, each unit tau is obtained by accumulation n Stress sigma at time n ＝∑{Δσ n }。
Further, the step of judging the safety condition of the dam body comprises the following steps: according to the formula
Calculating the safety coefficient K of the dam body f Wherein sigma is the sum of temperature stress generated by various temperature differences, and the unit is MPa; epsilon p The concrete limit pull-up value is set; e (E) c The elastic modulus of the concrete is expressed in MPa. The safety coefficient is more than 1.5 and is in a safe state, and the quality can be influenced by 1.3 to 1.5The amount is less than 1.3, the cracking risk exists, and the safety coefficient is less than 1.0, and the cracking risk is larger.
Further, if K f <1.5, paving heat preservation covers in a wet state on the surfaces of the dam bodies, and increasing the number of layers of the heat preservation covers; if K f And the surface of the dam body is not provided with a heat preservation quilt, and the dam body is judged to be free of cracking risk.
When the dam surface is at GK 1 : paving a heat preservation quilt in a wet state, GK 2 : poor laying of insulation quilt or GK 3 : if K is the case when any one of three states of the heat preservation quilt with water accumulation at the lower part is laid f(q) Not less than 1.5 and K f(q+1) <1.5, the dam surface state is configured as GK q The method comprises the steps of carrying out a first treatment on the surface of the Wherein q is the type number of the dam surface state, GK q For the surface state of the dam with the number of q, K f(q) The safety coefficient corresponding to the surface state of the q-th dam body. According to the thermal insulation measures of the dam body surface, the thermal insulation measures are reasonably adjusted according to the safety condition of the dam body, the thermal insulation is enhanced without cracking the dam body surface, further, the trial and error cost is avoided, and the high cost caused by excessive thermal insulation can be avoided.
In addition, the method for analyzing the temporary surface stress of the concrete dam body further comprises the following steps: simulating and calculating the temperature stress during the cold weather according to the predicted cold weather; calculating the safety coefficient K of the dam body according to the temperature stress f The method comprises the steps of carrying out a first treatment on the surface of the If the safety factor is K f If the temperature is less than 1.5, an early warning is issued, and the heat preservation of the dam body is enhanced. Wherein, the temperature data and solar radiation data are taken every three minutes, the cold tide early warning temperature is used as the predicted temperature, and the safety coefficient K of the cold tide duration period is calculated f If there is a safety factor K during the cold weather f Under the condition of less than 1.5, the heat preservation measure of the dam body is further enhanced so as to avoid cracking of the surface of the dam body due to local temperature difference during the cold tide.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (3)
1. The method for analyzing the temporary surface stress of the concrete dam body is characterized by comprising the following steps of:
determining a preset heat preservation state of the surface of the dam body;
determining a surface heat dissipation coefficient;
calculating a concrete temperature field according to the surface heat dissipation coefficient, and simulating and calculating temperature stress generated by temperature difference according to the concrete temperature field;
judging the safety condition of the dam body, and adjusting the thermal insulation measure of the surface of the dam body;
the step of determining the preset heat preservation state of the dam surface comprises the following steps: according to the surface state of the dam body, the surface of the dam body is divided into the following categories: GK (Gate Bipolar transistor) 1 : paving a heat preservation quilt in a wet state; GK (Gate Bipolar transistor) 2 : poor paving of the heat preservation quilt; GK (Gate Bipolar transistor) 3 : laying a heat preservation quilt with accumulated water at the lower part; the surface of the dam body is free of a heat preservation quilt;
under the condition that the surface of the dam body is not provided with a heat preservation quilt, detecting whether the wind speed of the surface of the dam body is larger than a preset wind speed; if the wind speed of the dam surface is less than or equal to the preset wind speed, the type of the dam surface is GK 4 : the first type is a state without heat preservation quilt; if the wind speed of the dam surface is larger than the preset wind speed, the type of the dam surface is GK 5 : the second type is a state without heat preservation quilt;
the step of judging the safety condition of the dam body comprises the following steps:
according to the formula
Calculating the safety coefficient K of the dam body f Wherein sigma is the sum of temperature stress generated by various temperature differences, and the unit is MPa; epsilon p The concrete limit pull-up value is set; e (E) c The elastic modulus of the concrete is expressed as MPa;
if K f <1.5, and the dam surface is paved with a wet stateThe number of layers of the heat preservation quilt is increased;
if K f Not less than 1.5, judging that the dam body has no cracking risk if the surface of the dam body has no heat preservation quilt;
if K f(q) Not less than 1.5 and K f(q+1) <1.5, configuring the dam surface state as GK q The method comprises the steps of carrying out a first treatment on the surface of the Wherein q is the type number of the dam surface state, GK q For the surface state of the dam with the number of q, K f(q) The safety coefficient corresponding to the surface state of the q-th dam body;
the method for analyzing the temporary surface stress of the concrete dam body further comprises the following steps: calculating the temperature stress during the cold weather according to the predicted cold weather simulation; calculating the safety coefficient K of the dam body according to the temperature stress f The method comprises the steps of carrying out a first treatment on the surface of the If the safety factor K f If the temperature is less than 1.5, issuing early warning and enhancing the heat preservation of the dam body;
the step of determining the surface heat dissipation factor includes:
preset value beta of preset surface heat dissipation coefficient 0 Simulating and measuring the initial calculation temperature of the test point;
the first error value is calculated according to the following formula,
wherein T is eer(1) The first error value is given in degrees celsius; n is the total number of steps of time divided in the calculation process; k (K) b(i0) Is the surface heat dissipation coefficient beta 0 Under the condition, the time step is the calculated temperature of the measuring point in the step i, and the unit is the temperature; k (K) c(i) The actual temperature of the measuring point is measured when the time step is the step i, and the unit is the temperature;
calculating the mth surface heat dissipation coefficient beta according to the following formula m ＝β 0 +Δβ· (m-1), where β m For the mth surface heat dissipation coefficient, delta beta is a preset increment value, and m is more than or equal to 2;
calculating the mth calculated temperature of the test point through simulation and calculation, calculating the mth error value according to the following formula,
wherein K is b(im) Is the surface heat dissipation coefficient beta m Under the condition, the time step is the calculated temperature of the measuring point in the step i;
up to T eer(m) <T eer(m+1) Then the surface heat dissipation coefficient β=β m 。
2. The method for analyzing the temporary face stress of the concrete dam according to claim 1, further comprising:
detecting environmental information with preset time as an interval, wherein the environmental information comprises temperature data and dam surface wind speed;
the preset time is 2-5 min.
3. The method of analyzing temporary face stress of a concrete dam according to claim 1, wherein said step of determining a surface heat dissipation factor comprises:
when the dam surface is not provided with the heat preservation quilt, the surface heat dissipation coefficient is calculated according to the following formula, wherein beta=523.2+324.72v a Wherein v is a The wind speed is the unit m/s of the surface of the dam body.
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