Method and system for determining wind profile parameters of site around high-rise building

Abstract

The invention discloses a method and system for determining wind profile parameters of a site around a high-rise building, and belongs to the technical field of high-rise building design. Wind speed time history data at different heights of a building site and basic wind pressure of a city are imported from an anemograph; calculating an average wind speed profile and a turbulence intensity profile of the site around the building according to the measured wind pressure time history; calculating wind speed profiles and turbulence intensity profiles of sites A, B, C and D according to the Building Load Standard GB 50009-2012; comparing the average wind speed and turbulence intensity profile of the site where the high-rise building is located with the four types of sites; and determining wind profile parameters of the site around the high-rise building. Based on the wind profile conversion theory, the wind profile parameters of the site around the high-rise building can be accurately determined.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-rise building design, and more specifically, relates to a method and system for determining wind profile parameters of a site surrounding a high-rise building. Background Art

[0002] High-rise buildings are the main building form in modern cities, and wind loads are the main horizontal loads on high-rise buildings. In the design of high-rise buildings, the wind profile parameters of the site around the building directly determine the size of the wind load. In engineering applications, it is generally believed that the wind profile conforms to the exponential law. The wind profile parameters are mainly related to the ground roughness. The "Building Structure Load Code GB50009-2012" divides the ground roughness categories into four types: offshore (Class A), rural (Class B), urban (Class C), and large cities (Class D). The wind profile indexes are 0.12, 0.15, 0.22, and 0.30, respectively, and the corresponding ground roughness categories are defined for each city based on previous observation data.

[0003] However, with the development of domestic cities, the thickness of the atmospheric boundary layer under urban landforms has increased significantly compared with the original; on the other hand, the wind profile categories defined by city are too rough for a single construction project. Summary of the invention

[0004] In view of the above defects or improvement needs of the prior art, the present invention proposes a method and system for determining wind profile parameters of a site around a high-rise building based on wind profile conversion theory.

[0005] To achieve the above object, according to one aspect of the present invention, a method for determining wind profile parameters of a site around a high-rise building is provided, comprising:

[0006] Obtain wind speed time history data at different heights of the building site and the basic wind pressure of the city;

[0007] Calculate the average wind speed profile and turbulence intensity profile of the area around the building based on the wind speed time history data and the basic wind pressure of the city;

[0008] Calculate the wind speed profile and turbulence intensity profile for 4 types of sites: A, B, C, and D;

[0009] The average wind speed profile and turbulence intensity profile of the site around the high-rise building are compared with the wind speed profile and turbulence intensity profile of the four types of sites to determine the wind profile parameters of the site around the high-rise building.

[0010] In some optional embodiments, Calculate the turbulence intensity profile I(z) of the area around the building, where σ(z) is the standard deviation of the fluctuating wind speed, The average wind speed U(z,tn ) represents the nth wind speed time series collected at height z, and n is the number of wind speed time series collected.

[0011] In some optional embodiments, Calculates average wind speed profiles for sites of category A, B, C and D Where k is the corresponding site category, k = 1 represents a Class A site, k = 2 represents a Class B site, k = 3 represents a Class C site, k = 4 represents a Class D site, α k is the surface roughness index, z is the height of the anemometer, is the average wind speed at a height of 10 meters above the ground, w0 is the basic wind pressure of the city where the building is located, ρ is the air density, H Tk is the gradient wind height of the site, H TB is the gradient wind height of the B-type site, α B It is the wind profile index of Class B site.

[0012] In some optional embodiments, Calculation of turbulence intensity profiles for sites of type A, B, C and D I k (z), where I 10 is the turbulence intensity at a height of 10 m, and z is the height of the anemometer.

[0013] In some optional implementation schemes, the average wind speed profile and turbulence intensity profile of the site surrounding the high-rise building are compared with the wind speed profiles and turbulence intensity profiles of the four types of sites to determine the wind profile parameters of the site surrounding the high-rise building, including:

[0014] If the average wind speed profile at the height of the building is less than or equal to the Class D average wind speed profile, and the turbulence intensity profile at the height of the building is greater than or equal to the Class D turbulence intensity profile, the site parameters around the building are Class D;

[0015] If the average wind speed profile at a certain height of the building site is greater than the Class D average wind speed profile or the turbulence intensity profile is less than the Class D turbulence intensity profile, but the average wind speed profile at all heights is less than or equal to the Class C average wind speed profile, and the turbulence intensity profile is greater than or equal to the Class C turbulence intensity profile, then the site parameters around the building are Class C;

[0016] If the average wind speed profile at a certain height of the building site is greater than the Class C average wind speed profile or the turbulence intensity profile is less than the Class C turbulence intensity profile, but the average wind speed profile at all heights is less than or equal to the Class B average wind speed profile, and the turbulence intensity profile is greater than or equal to the Class B turbulence intensity profile, then the site parameters around the building are Class B;

[0017] If the average wind speed profile at a certain height of the building site is greater than the Class B average wind speed profile or the turbulence intensity profile is less than the Class B turbulence intensity profile, the site parameters around the building are Class A.

[0018] According to another aspect of the present invention, there is provided a system for determining wind profile parameters of a site around a high-rise building, comprising: n anemometers and a processing module installed at different heights of the building facade;

[0019] The processing module is used to execute the steps of any one of the above methods according to the wind speed time history data at different heights of the building site obtained by the anemometer and the basic wind pressure of the city.

[0020] In some optional embodiments, the anemometers are distributed densely at the bottom of the building and sparsely at the top.

[0021] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0022] The invention imports wind speed time history data at different heights of the building site and the basic wind pressure of the city from an anemometer; calculates the average wind speed profile and turbulence intensity profile of the site around the building according to the measured wind pressure time history; calculates the wind speed profile and turbulence intensity profile of sites A, B, C, and D according to the "Building Load Code GB 50009-2012"; compares the average wind speed and turbulence intensity profile of the site where the high-rise building is located with those of the four types of sites; and determines the wind profile parameters of the site around the high-rise building. Based on the wind profile conversion theory, the wind profile parameters of the site around the high-rise building can be accurately determined. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of wind profile conversion around a high-rise building provided by an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of a system for determining wind profile parameters of a site around a high-rise building provided by an embodiment of the present invention;

[0025] Figure 3 It is a flow chart of a method for determining wind profile parameters of a site around a high-rise building provided by an embodiment of the present invention;

[0026] Figure 4 An average wind speed of a site around a high-rise building in an embodiment of the present invention is provided in an embodiment of the present invention;

[0027] Figure 5 The present invention provides a turbulence intensity of a site around a high-rise building. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0029] like Figure 3 As shown, a method for determining wind profile parameters of a site around a high-rise building provided by an embodiment of the present invention includes the following steps:

[0030] 1) Import wind speed time history data at different heights of the building site and the basic wind pressure of the city from the anemometer;

[0031] 2) Calculate the average wind speed profile and turbulence intensity profile of the area around the building based on the measured wind pressure time history;

[0032] 3) Calculate the wind speed profile and turbulence intensity profile of sites A, B, C, and D according to the Building Load Code GB 50009-2012;

[0033] 4) Compare the average wind speed and turbulence intensity profiles of the site where the high-rise building is located with those of the four types of sites;

[0034] 5) Determine the wind profile parameters of the site around high-rise buildings.

[0035] Figure 1 This is a schematic diagram of the wind profile conversion around high-rise buildings. When the near-ground wind enters another ground roughness site from one ground roughness site, its wind profile changes gradually. After a certain ground distance, a stable wind profile of a new roughness category will be formed.

[0036] Figure 2 The schematic diagram of the wind profile parameter determination system around a high-rise building is shown in Figure 1. n anemometers are installed at different heights on the building facade. The anemometer distribution principle is dense at the bottom of the building and sparse at the top. The wind speed time series collected by the anemometer at height z is U z (t), the average wind speed profile and turbulence intensity profile of the site where the high-rise building is located are calculated based on the collected wind speed time history data. The turbulence intensity is calculated according to the following formula:

[0037]

[0038] Where: σ(z) is the standard deviation of fluctuating wind speed, The average wind speed U(z,t n ) represents the nth wind speed time series collected at height z, and n is the number of wind speed time series collected.

[0039] According to the Building Load Code GB 50009-2012, the average wind speed and turbulence intensity profiles for Class A, B, C and D sites are calculated. The average wind speed is determined according to the following formula:

[0040]

[0041] Where: k is the corresponding site category, k = 1 represents a Class A site, and so on; α k is the surface roughness index, which is 0.12, 0.15, 0.22 and 0.30 for sites of categories A, B, C and D respectively; is the average wind speed at a height of 10 meters above the ground, calculated according to the following formula:

[0042]

[0043] Where: w0 is the basic wind pressure of the city where the building is located; ρ is the air density; H Tk is the gradient wind height of the site, which is 300, 350, 450 and 550m for sites of type A, B, C and D respectively. TB is the gradient wind height for Class B sites.

[0044] The turbulence intensity profile is determined as follows:

[0045]

[0046] Where: I 10 is the turbulence intensity at a height of 10 m, which are 0.12, 0.14, 0.23 and 0.39 for sites of types A, B, C and D respectively, and z is the height of the anemometer.

[0047] The average wind speed and turbulence intensity of the site where the high-rise building is located are compared with the four types of sites in the "Building Load Code GB 50009-2012".

[0048] 1) If the average wind speed at all building heights is less than or equal to Class D, and the turbulence intensity profile is greater than or equal to Class D, the site parameters around the building are Class D;

[0049] 2) If the average wind speed at a certain height of the building site is greater than Class D or the turbulence intensity is less than Class D, but the average wind speed at all heights is less than or equal to Class C, and the turbulence intensity is greater than or equal to Class C, then the site parameters around the building are Class C;

[0050] 3) If the average wind speed at a certain height of the building site is greater than Class C or the turbulence intensity is less than Class C, but the average wind speed at all heights is less than or equal to Class B, and the turbulence intensity is greater than or equal to Class B, then the site parameters around the building are Class B;

[0051] 4) If the average wind speed at a certain height on the building site is greater than Class B or the turbulence intensity is less than Class B, the site parameters around the building shall be Class A.

[0052] like Figure 2 As shown in the figure, for the field test around a high-rise building, anemometers are installed at the building heights of 0.057H, 0.086H, 0.143H, 0.214H, 0.286H, 0.429H, 0.571H, 0.714H, 0.857H and 1.000H. The measured wind speed time series are U1(t), U2(t)…U 10 (t). The calculated average wind speed and turbulence intensity are: and I(z1), I(z2)…I(z 10 ) The local urban site category specified in the "Building Load Code GB 50009-2012" is Class A, and the 50-year basic wind pressure is 0.45kN / m 2 The calculated average wind speed at 10 m is 30.40 m / s. According to the present invention, the measured data of the average wind speed and turbulence intensity of the site around the high-rise building are obtained, and the average wind speed and turbulence intensity data of the A, B, C and D class sites are as follows: Figure 4 and Figure 5 As shown in the figure, it can be determined that the wind profile parameters of the site around the high-rise building can be corrected from Class A to Class B.

[0053] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0054] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining wind profile parameters around a high-rise building, characterized in that: include: Obtain wind speed time history data at different heights of the building site and the basic wind pressure of the city; Calculate the average wind speed profile and turbulence intensity profile of the area around the building based on the wind speed time history data and the basic wind pressure of the city; Calculate the wind speed profile and turbulence intensity profile for 4 types of sites: A, B, C, and D; The average wind speed profile and turbulence intensity profile of the site around the high-rise building are compared with the wind speed profile and turbulence intensity profile of the four types of sites to determine the wind profile parameters of the site around the high-rise building.

2. The method according to claim 1, characterized in that Depend on Calculate the turbulence intensity profile I(z) of the area around the building, where σ(z) is the standard deviation of the fluctuating wind speed, is the average wind speed, U(z,t n ) represents the nth wind speed time series collected at height z, and n is the number of wind speed time series collected.

3. The method according to claim 2, characterized in that Depend on Calculates average wind speed profiles for sites of category A, B, C and D Where k is the corresponding site category, k = 1 represents a Class A site, k = 2 represents a Class B site, k = 3 represents a Class C site, k = 4 represents a Class D site, α k is the surface roughness index, z is the height of the anemometer, is the average wind speed at a height of 10 meters above the ground, w0 is the basic wind pressure of the city where the building is located, ρ is the air density, H Tk is the gradient wind height of the site, H TB is the gradient wind height of the B-type site, α B It is the wind profile index of Class B site.

4. The method according to claim 3, characterized in that Depend on Calculation of turbulence intensity profiles for sites of type A, B, C and D I k (z), where I 10 is the turbulence intensity at a height of 10m, and z is the height of the anemometer.

5. The method according to claim 4, characterized in that The wind profile parameters of the site around the high-rise building are determined by comparing the average wind speed profile and turbulence intensity profile of the site around the high-rise building with the wind speed profile and turbulence intensity profile of the four types of sites, including: If the average wind speed profile at the height of the building is less than or equal to the Class D average wind speed profile, and the turbulence intensity profile at the height of the building is greater than or equal to the Class D turbulence intensity profile, the site parameters around the building are Class D; If the average wind speed profile at a certain height of the building site is greater than the Class D average wind speed profile or the turbulence intensity profile is less than the Class D turbulence intensity profile, but the average wind speed profile at all heights is less than or equal to the Class C average wind speed profile, and the turbulence intensity profile is greater than or equal to the Class C turbulence intensity profile, then the site parameters around the building are Class C; If the average wind speed profile at a certain height of the building site is greater than the Class C average wind speed profile or the turbulence intensity profile is less than the Class C turbulence intensity profile, but the average wind speed profile at all heights is less than or equal to the Class B average wind speed profile, and the turbulence intensity profile is greater than or equal to the Class B turbulence intensity profile, then the site parameters around the building are Class B; If the average wind speed profile at a certain height of the building site is greater than the Class B average wind speed profile or the turbulence intensity profile is less than the Class B turbulence intensity profile, the site parameters around the building are Class A.

6. A system for determining wind profile parameters around a high-rise building, characterized in that: include: n anemometers and processing modules installed at different heights on the building facade; The processing module is used to execute the steps of the method according to any one of claims 1 to 5 based on the wind speed time history data at different heights of the building site obtained by the anemometer and the basic wind pressure of the city.

7. The system according to claim 6, characterized in that The anemometers are densely distributed at the bottom of the building and sparsely distributed at the top.

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