1. A cooling effect maximization-oriented urban green roof adaptive scale decision method is characterized by comprising the following steps:

acquiring preset parameters, and constructing a cooling effect sum model of green roofs in the region based on the preset parameters;

obtaining a constraint factor for maximizing the cooling effect of the green roof, and constructing a constraint evaluation model based on the constraint factor;

constructing an urban green roof adaptive construction scale decision model facing the maximization of the cooling effect by fusing the cooling effect sum model of the green roofs in the region with the constraint evaluation model;

and solving an objective function of the decision model for the urban green roof adaptive scale for the maximization of the cooling effect to obtain the urban green roof adaptive scale for the maximization of the cooling effect.

2. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 1, characterized in that:

the preset parameters include: single green roof area, greening vegetation type, single green roof slope, number of green roofs in the area.

3. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 1, characterized in that:

the constraint factors include: the total area of the building roof greening suitable construction, the total investment, the building roof greening suitability grade and the greening vegetation type.

4. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 1, characterized in that:

the total model expression of the cooling effect of the green roof in the area is as follows:

in the formula, EF represents the total cooling effect of n green roofs; s_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; g_iThe slope of the ith roof; delta T_i(y_ij,g_i) Denotes the i-th roof at a slope g_iThe self cooling strength of the roof under the condition of planting the j-type vegetation; r_iThe maximum cooling distance of the ith roof to the surrounding environment; s_RiFor the ith roof at radius R_iBuffer area within range; delta T_Ri(y_ij,g_i) For the ith roof at gradient g_iAnd the cooling intensity to the surrounding environment under the condition of planting the j-th vegetation.

5. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 1, characterized in that:

the objective function of the green roof adaptive scale decision model for the maximization of the cooling effect is as follows:

in the formula, MaxEF represents that the total cooling effect of the n green roofs is maximized; s_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; g_iThe slope of the ith roof; delta T_i(y_ij,g_i) Denotes the i-th roof at a slope g_iThe self cooling strength of the roof under the condition of planting the j-type vegetation; r_iThe maximum cooling distance of the ith roof to the surrounding environment; s_RiFor the ith roof at radius R_iBuffer area within range; delta T_Ri(y_ij,g_i) For the ith roof at gradient g_iAnd the cooling intensity to the surrounding environment under the condition of planting the j-th vegetation.

6. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 3, characterized in that:

the constraint evaluation model includes: a construction scale constraint model, a construction cost constraint model and a roof greening adaptability constraint model.

7. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 6, characterized in that:

the construction scale constraint model is used for limiting the maximum construction scale of the green roof, the maximum construction scale of the green roof is smaller than or equal to the total area of the greening suitability assessment of the building roof, and the expression of the construction scale constraint model is as follows:

x_i∈{0，1}，i＝1，2，...，n，

in the formula S_iIs the area of the ith roof; s_total(ii) a total area for the building roof greening suitability assessment; x is the number of_iWhether the ith roof is selected for greening or not.

8. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 6, characterized in that:

the construction cost constraint model is used for limiting the total construction cost of the green roof, the total construction cost of the green roof is less than or equal to the total investment, and the expression of the construction cost constraint model is as follows:

in the formula C_jConstruction cost per unit area for planting of j-th vegetation, C_totalFor total investment, S_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; x is the number of_iWhether the ith roof is selected for greening or not.

9. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 6, characterized in that:

the roof greening suitability constraint model is used for limiting the building roof greening suitability grade, and the building roof greening suitability grade is matched with the type of greening vegetation.

10. The cooling effect maximization-oriented urban green roof adaptive scale decision method according to claim 1, characterized in that:

the solving method of the objective function comprises the following steps: and (3) performing approximate optimal solution solving on the objective function by using a genetic algorithm to obtain the suitable construction scale of the urban green roof for the maximum cooling effect.

Background

There are three main categories of research methods on the cooling effect of green roofs: the method comprises the following steps of firstly, comparing the temperature change before and after the construction of the green roof based on actual observation (including field monitoring and remote sensing); the statistical modeling and simulation method is used for verifying, analyzing and predicting the temperature changes of different green roof scenes by modeling simulation alone or combining field observation and experimental methods; and thirdly, an experimental method, wherein the cooling effect caused by the surface characteristic change of the green roof is analyzed through the measurement result collected by the experimental site. The field experiment shows that the green roofs of different plant types have the capacity of cooling the surface of the roof, but the cooling effect is different, compared with the traditional roof, the daily maximum surface temperature of the roof subjected to greening can be reduced by 10-30 ℃, and the simulation on the scale of buildings and blocks shows the effect consistent with the field experiment.

In recent years, environmental remote sensing is widely applied to urban heat island effect research, and urban scale thermal environment is comprehensively characterized within a specific time. Although the urban surface temperature of the environment remote sensing inversion is not equal to the atmospheric temperature, researches prove that the surface temperature is highly related to the near-ground air temperature, and the surface temperature is widely used for checking the relation between the heat island effect and the urban surface parameters. On a city scale, numerical simulations and statistical analysis are used to predict different green rooftop scenes, such as weather forecast model (WRF) coupled city canopy patterns. Santamouris reviewed cooling simulation studies on green roofs and found that implementation of green roofs at urban levels reduced the average ambient temperature by 0.3-3K. However, these simulations are purely theoretical, while assuming that a 100% roof implements a broad green roof. Other studies have simulated some green roof implementations, for example, Li et al have shown that over 30% of roof implementations of green roofs can achieve a 0.2 ℃ reduction in air temperature of 2m near the ground; imran et al showed that by implementing 30% -90% green roofs, the maximum surface temperature was reduced by 1-3.8 deg.C; huang et al found that 50% roofing using green roofing technology can reduce the air temperature by 0.5 ℃ 2m near the ground.

The construction scale of the urban green roof is influenced by a plurality of socioeconomic factors such as construction cost, building roof greening suitability and the like, no good solution exists at present, and the socioeconomic factors are all taken into consideration once when the construction scale area of the green roof in the region is calculated.

Disclosure of Invention

The invention aims to provide a cooling effect maximization-oriented urban green roof adaptive scale decision method, which is used for solving the problems in the prior art and converting the problem of determining the adaptive scale into a target optimization problem supported by a plurality of decision variables and constraint conditions.

In order to achieve the purpose, the invention provides the following scheme: the invention provides a cooling effect maximization-oriented urban green roof construction scale decision method, which comprises the following steps:

acquiring preset parameters, and constructing a cooling effect sum model of green roofs in the region based on the preset parameters;

obtaining a constraint factor for maximizing the cooling effect of the green roof, and constructing a constraint evaluation model based on the constraint factor;

constructing an urban green roof adaptive construction scale decision model facing the maximization of the cooling effect by fusing the cooling effect sum model of the green roofs in the region with the constraint evaluation model;

and solving an objective function of the decision model for the urban green roof adaptive scale for the maximization of the cooling effect to obtain the urban green roof adaptive scale for the maximization of the cooling effect.

Preferably, the preset parameters include: single green roof area, greening vegetation type, single green roof slope, number of green roofs in the area.

Preferably, the constraint factor includes: the total area of the building roof greening suitable construction, the total investment, the building roof greening suitability grade and the greening vegetation type.

Preferably, the expression of the total model of the cooling effect of the green roofs in the zones is as follows:

in the formula, EF represents the total cooling effect of n green roofs; s_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; g_iThe slope of the ith roof; delta T_i(y_ij,g_i) Denotes the i-th roof at a slope g_iThe self cooling strength of the roof under the condition of planting the j-type vegetation; r_iThe maximum cooling distance of the ith roof to the surrounding environment; s_RiFor the ith roof at radius R_iBuffer area within range; delta T_Ri(y_ij,g_i) For the ith roof at gradient g_iAnd the cooling intensity to the surrounding environment under the condition of planting the j-th vegetation.

Preferably, the objective function of the green roof adaptive scale decision model for maximizing the cooling effect is as follows:

in the formula, MaxEF represents that the total cooling effect of the n green roofs is maximized; s_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; g_iThe slope of the ith roof; delta T_i(y_ij,g_i) Denotes the i-th roof at a slope g_iThe self cooling strength of the roof under the condition of planting the j-type vegetation; r_iThe maximum cooling distance of the ith roof to the surrounding environment; s_RiFor the ith roof at radius R_iBuffer area within range; delta T_Ri(y_ij,g_i) For the ith roof at gradient g_iAnd the cooling intensity to the surrounding environment under the condition of planting the j-th vegetation.

Preferably, the constraint evaluation model includes: a construction scale constraint model, a construction cost constraint model and a roof greening adaptability constraint model.

Preferably, the construction scale constraint model is used for limiting the maximum construction scale of the green roof, the maximum construction scale of the green roof is smaller than or equal to the total area of the greening suitability assessment of the building roof, and the expression of the construction scale constraint model is as follows:

wherein Si is the area of the ith roof; s_total(ii) a total area for the building roof greening suitability assessment; x is the number of_iAnd (4) greening the ith roof.

Preferably, the construction cost constraint model is configured to limit the total construction cost of the green roof, where the total construction cost of the green roof is less than or equal to the total investment, and an expression of the construction cost constraint model is as follows:

in the formula C_jConstruction cost per unit area for planting of j-th vegetation, C_totalFor total investment, S_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; x is the number of_iAnd (4) greening the ith roof.

Preferably, the roof greening suitability constraint model is used for limiting the building roof greening suitability grade, and the building roof greening suitability grade is matched with the type of the greening vegetation.

Preferably, the solution method of the objective function is as follows: and (3) performing approximate optimal solution solving on the objective function by using a genetic algorithm to obtain the suitable construction scale of the urban green roof for the maximum cooling effect.

The invention discloses the following technical effects:

the invention provides a cooling effect maximization-oriented urban green roof adaptive scale decision method, which is used for converting a problem of determining an adaptive scale into a target optimization problem supported by a plurality of decision variables and constraint conditions aiming at different types of green roofs and aiming at the influence of various social and economic factors, further constructing a cooling effect maximization-oriented urban green roof adaptive scale decision model and clarifying a quantitative relation between the urban scale green roof adaptive scale and a cooling effect, thereby realizing scientific decision of the green roof adaptive scale, having important application value in the aspect of the scientific decision of the green roof adaptive scale and providing reference for making a cooling effect maximization-oriented roof adaptive scale decision plan.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a flow chart of a cooling effect maximization oriented urban green roof construction scale decision method in the embodiment of the invention;

FIG. 2 is a graph of the average temperature difference between the green roof and the multi-stage buffer ring in accordance with an embodiment of the present invention;

FIG. 3 is a plot of the fitted regression of green roof average temperature versus green roof area for an embodiment of the present invention;

FIG. 4 is a graph of the fitted regression of the average temperature of the 100m buffer versus the green roof area in an embodiment of the present invention;

FIG. 5 is a diagram of the construction scale and layout of a multi-condition-limited green roof of a lower mansion gate island according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Referring to fig. 1, the present embodiment provides a method for deciding an applicable scale of an urban green roof for maximizing a cooling effect, including:

s1, acquiring preset parameters, wherein the preset parameters comprise: single green roof area, greening vegetation type, single green roof slope, number of green roofs in the area; and constructing a cooling effect sum model of the green roofs in the region based on preset parameters.

The construction of the green roof can play a role in reducing the temperature of the roof and the surrounding constructed environment, so that the cooling effect of a single green roof is the sum of the cooling effect of the roof and the cooling effect on the surrounding environment. Wherein the self cooling effect of the single green roof is S_i·ΔT_i(y_ij,g_i) The cooling effect of a single green roof on the surrounding environment is S_Ri·ΔT_Ri(y_ij,g_i)。

The total model expression of the cooling effect of the green roof in the area is as follows:

in the formula, EF represents the total cooling effect of n green roofs; s_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; g_iThe slope of the ith roof; delta T_i(y_ij,g_i) Denotes the i-th roof at a slope g_iThe self cooling strength of the roof under the condition of planting the j-type vegetation; r_iThe maximum cooling distance of the ith roof to the surrounding environment; s_RiFor the ith roof at radius R_iBuffer area within range; delta T_Ri(y_ij,g_i) For the ith roof at gradient g_iAnd the cooling intensity to the surrounding environment under the condition of planting the j-th vegetation.

S2, obtaining a constraint factor for maximizing the green roof cooling effect, wherein the constraint factor comprises: building roof greening suitability total area, investment sum, building roof greening suitability grade and greening vegetation type; constructing a constraint evaluation model based on the constraint factors;

the constraint evaluation model comprises: a construction scale constraint model, a construction cost constraint model and a roof greening adaptability constraint model.

The construction scale constraint model is used for limiting the maximum construction scale of the green roof, the maximum construction scale of the green roof is smaller than or equal to the total area of the greening adaptability evaluation of the building roof, and the expression of the construction scale constraint model is as follows:

in the formula S_iIs the area of the ith roof; s_totalTotal area for building roof greening suitability assessment; x is the number of_iWhether greening is carried out on the ith roof or not is judged, and if greening is selected to be carried out on the ith roof, the value is assigned to be 1; if the roof is not selected for greening, the value is assigned to 0.

The construction cost constraint model is used for limiting the total construction cost of the green roof, the total construction cost of the green roof is less than or equal to the total investment, and the expression of the construction cost constraint model is as follows:

in the formula C_jConstruction cost per unit area for planting of j-th vegetation, C_totalFor total investment, S_iIs the area of the ith roof; x is the number of_iWhether greening is carried out on the ith roof or not;

greening vegetation of the green roof can be divided into three types of trees, shrubs and grass; the construction cost per unit area of green roofs of different vegetation types is different; the area of the green roof of different greening vegetation types is multiplied by the construction cost per unit area of the green roof of the type, and the construction cost of all the green roofs is the construction cost of all the green roofs, and the cost cannot exceed the total investment.

The roof greening suitability constraint model is used for limiting the building roof greening suitability grade, and the building roof greening suitability grade is matched with the type of greening vegetation;

in the formula SL_iGreening building roof construction suitability grade for the ith roof;

namely: if the roof is "perfectly built," trees or shrubs may be selected for planting; if the roof is "built-in", shrubs or grass may be selected; if the roof is "unfit" then the roof is not greened and is not counted for.

S3, fusing a cooling effect sum model of the green roofs in the region with a constraint evaluation model to construct an urban green roof adaptive construction scale decision model for maximizing the cooling effect;

the objective function of the urban green roof adaptive scale decision model for maximizing the cooling effect is as follows:

in the formula, MaxEF represents that the total cooling effect of the n green roofs is maximized; s_iIs the area of the ith roof; y is_ijPlanting the jth vegetation on the ith roof; g_iThe slope of the ith roof; delta T_i(y_ij,g_i) Denotes the i-th roof at a slope g_iThe self cooling strength of the roof under the condition of planting the j-type vegetation; r_iThe maximum cooling distance of the ith roof to the surrounding environment; s_RiFor the ith roof at radius R_iBuffer area within range; delta T_Ri(y_ij,g_i) For the ith roof at gradient g_iAnd the cooling intensity to the surrounding environment under the condition of planting the j-th vegetation.

And S4, further using a genetic algorithm to carry out approximate optimal solution solving on the objective function of the urban green roof adaptive scale decision model with the maximized facing cooling effect, and finally obtaining the urban green roof adaptive scale with the maximized cooling effect.

For a better understanding of the present invention, the following examples are given to illustrate the present model in further detail:

and determining the construction scale of the green roof of the building door island according to the decision model for the construction scale of the green roof of the city under the condition of maximizing the cooling effect.

Firstly, constructing a cooling effect sum model of a green roof in an island region of a building.

The calculated average temperature of the green roofs of the mansion islands in 2014 and 2017 and the average surface temperature difference of the multi-stage buffer zones are shown in figure 2, and the result shows that the temperature difference after the roof greening is carried out in the buffer zone range of 30-150m also has the tendency of being smaller than the temperature difference before the roof greening is carried out, and the temperature difference is calculated according to the principle that the temperature difference after the roof greening is carried outTherefore, the maximum cooling distance of the building island roof greening to the surrounding environment is about 100-150 m. The correlation between the average temperature of the green roof and the characteristic cooling buffer zone (100m) of the green roof and the green roof area is analyzed by taking a single roof as a research object (figures 3 and 4), and the result shows that the green roof area does not exceed 10000m²In the case of (2), the average temperature in the greening roof and the 100m buffer zone after greening is performed is in a negative correlation with the area of the greening roof, that is, the cooling effect of the greening roof is more obvious as the area of the greening roof is increased.

And secondly, constructing a constraint evaluation model by taking the maximization of the cooling effect of the green roofs of the high-density urban areas of the mansion islands as a target, and respectively bringing constraint factors such as the total construction area of the greening roofs of the buildings, the total investment, the construction suitability level of the greening roofs of the buildings, the type of greening vegetation and the like into the constraint evaluation model.

The calculated total area of the building island green roof construction maximum scale cannot break through the building roof greening suitability evaluation, namely, the total area does not exceed 1192 ten thousand meters²(ii) a The total construction cost of all green roofs of the mansion islands does not exceed the total investment, namely the total investment of 20 billion yuan RMB is not exceeded; according to different greening suitability levels of the building roof, the building roof selects different greening vegetation types.

Thirdly, constructing a set of green roof adaptive scale decision model with the building door island maximized for the cooling effect, wherein the objective function of the city green roof adaptive scale decision model with the building door island maximized for the cooling effect is as follows:

fourthly, performing approximate optimal solution solving on an objective function of the urban green roof adaptive scale decision model with the maximized facing cooling effect by using a genetic algorithm, and finally obtaining 714 ten thousand meters of urban green roof adaptive scale with the maximized facing cooling effect under the condition that the Xiamen island is limited by the total investment of 20 hundred million RMB²And the green roof of the mansion door island is suitable for construction under the condition of simulating multiple conditionsScale and layout, as in fig. 5.

In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, are merely for convenience of description of the present invention, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.