Wind-resistant design method for multi-tower-belt connected building

Abstract

The invention discloses a wind resistance design method for a multi-tower-belt connected building, which belongs to the technical field of building wind resistance and comprises the following steps: S1, establishing a finite element model of a connected building structure; s2, optimizing the finite element model; s3, simulating a wind pressure time history of the connected building based on standard wind load parameters, and performing dynamic analysis and comfort analysis on the finite element model; s4, obtaining a wind pressure coefficient time history of the connected building based on a wind tunnel test structure, and performing dynamic analysis and comfort analysis on the finite element model; s5, adjusting internal force parameters of the finite element model; and S6, performing safety and comfort evaluation on the connected building. The node wind pressure time history obtained by the wind tunnel test is converted into the node concentrated load creatively, a calculation formula is provided, the concentrated load at the most unfavorable wind direction angle is applied to the corresponding node of the finite element model, and wind vibration response time history analysis is performed. And the wind load effect calculation accuracy and the comfort checking calculation accuracy of the connected building are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of wind-resistant buildings, and in particular relates to a wind-resistant design method for a multi-tower connected building. Background Art

[0002] With the advancement of urbanization in recent years, there are more and more high-rise landmark buildings. Among them, the conjoined building structure has become a common high-rise building design form in recent years. The towers of the conjoined buildings are connected to each other through connectors, which can be used as corridors, bringing great convenience to the use of high-rise buildings. From the perspective of architectural modeling, it increases the diversity of architectural modeling, making it novel and beautiful. However, the floor plans, floor heights, and number of floors of the high-rise towers at both ends of the connector are often significantly different, and the dynamic characteristics of the tower structures vary greatly. For such structures, the calculation of wind loads according to conventional methods in the specifications is no longer completely applicable, and the calculation accuracy cannot be guaranteed. Especially in coastal cities, the wind load is large, and some areas have frequent typhoon activities every year. The wind resistance of the structure is the main safety control factor, which puts higher requirements on the calculation accuracy of wind loads.

[0003] The wind interference effect of connected buildings is more obvious. Its wind load characteristics include average wind load and pulsating wind load, which are greatly affected by its own body shape and surrounding buildings. The wind load on the tower in the connected building will be greatly different from the wind load on the single high-rise building due to the existence of another tower. The narrow passage formed between the two towers will also increase the wind field flow velocity and wind pressure. Since the connector connects the towers together, the dynamic characteristics of the connected structure are inherently more complex than those of a single building. In addition, it is exposed to the turbulent wind field of the atmospheric boundary layer. The pulsating effect of the wind load is often affected by the characteristic turbulence of the blunt body, which is expressed as a more complex and sensitive dynamic effect. Based on the wind vibration coefficient regulations in the code, it is difficult to meet the design accuracy requirements; at the same time, when analyzing its wind-induced vibration, the coupled vibration effect of multiple towers must be considered.

[0004] The connector is an important part that connects the towers, and it often has the characteristics of large span and large flow of people. The comfort of the connector should be verified. The load specification provides a calculation formula for the wind vibration acceleration in the downwind direction for "high-rise buildings with uniform distribution of size and mass along the height", but it is not applicable to the complex structure of the connector and cannot be used to verify the wind vibration acceleration of the connector. Summary of the invention

[0005] The purpose of the present invention is to provide a wind-resistant design method for a multi-tower connected building to solve the problems of inaccurate calculation of wind loads on connected buildings and inaccurate verification of the comfort of the connector using traditional methods in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A wind-resistant design method for a multi-tower connected building comprises the following steps:

[0008] S1. Establish a finite element model of the connected building structure;

[0009] S2. Optimize the finite element model so that the interlayer displacement angle β of the finite element model i The inter-story displacement limit [β] specified in the corresponding code shall not be exceeded, and the effectiveness of the three effects of structural members, connection nodes and connected building supports S i Not exceeding the corresponding structural resistance R;

[0010] S3. Based on the wind load parameters of the specification, the wind pressure time history of the connected building is simulated, and the dynamic analysis and comfort analysis of the finite element model are performed to obtain the maximum shear force V of the structural base. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i and the mean acceleration of the connector α1;

[0011] S4. Based on the wind tunnel test structure, the wind pressure coefficient time history of the connected building is obtained, and the dynamic analysis and comfort analysis of the finite element model are performed to obtain the maximum shear force V of the structural base. 2.max , structural deformation, maximum reaction force R of the connected building support 2.i and the mean acceleration of the connected body, α2;

[0012] S5. Adjust the internal force parameters of the finite element model. The adjustment coefficient of the base shear force is π, π=max(V 1.max , V 2.max ) / V0, where V0 is the initial base shear value of the finite element model obtained in step S2; when π≤1, π=1 is taken, and there is no need to adjust the internal force parameters;

[0013] S6: The maximum value R of the structural deformation and the reaction force of the connected building support obtained twice in steps S3 and S4 1.i , R 2.i and the mean acceleration α1 and α2 of the connector, the safety and comfort of the connected building are evaluated, and the finite element model is adjusted to meet R 1.i <[R]andi 2.i <[R], [R] is the bearing capacity limit of the support of the connected building, and satisfies α1<[α] and α2<[α], [α] is the comfort acceleration limit specified in the code.

[0014] Further, step S4 includes:

[0015] S41. Conduct a scaled model wind tunnel test on the connected building, and obtain the wind pressure coefficient time history of each node of the connected building at each wind direction angle according to the wind tunnel test results;

[0016] S42. Convert the wind pressure coefficient time history of the node into the concentrated load of the node. The calculation formula is: j (t) = w0μ z A j C P,j (t);

[0017] Among them, p j (t) is the concentrated load of the jth node at time t; ω0 is the basic wind pressure; μ z A is the wind pressure height coefficient at the wind pressure reference point; j is the wind-affected area of ​​the jth node; C p,j (t) is the wind pressure coefficient of the jth node at time t;

[0018] S43, select the most unfavorable wind direction angle;

[0019] S44, applying the concentrated load under the most unfavorable wind direction angle to the corresponding nodes of the finite element model, and performing a wind-induced vibration response time history analysis;

[0020] S45. The maximum shear force V of the structural base is obtained through dynamic calculation 2.max , structural deformation, maximum reaction force R of the connected building support 2.i ;

[0021] S46. According to step S44, the mean acceleration α2 of the connector under the most unfavorable wind direction angle is obtained.

[0022] Further, step S3 includes:

[0023] S31. The wind pressure time history of the connected building is obtained by using the wind pressure time history simulation method. The wind pressure time history of each floor of each tower is applied to the corresponding floor gravity center position, and the wind vibration response time history analysis of the structure is performed. The maximum shear force V of the structure base is obtained by dynamic calculation. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i ;

[0024] S32. Use the 10-year return period wind pressure time history to perform wind vibration response time history analysis on the finite element model to obtain the acceleration time history response of each point of the connector and the mean acceleration α1 of the connector.

[0025] Furthermore, in step S31, the wind pressure time history simulation method is: according to the standard wind pressure, ground roughness category, body coefficient and calculated floor height, the wind pressure time history of each floor of each tower of the connected building is simulated by time domain analysis method.

[0026] Further, step S2 includes:

[0027] S21. Perform structural stress analysis on the finite element model under equivalent static wind load to obtain the inter-layer displacement angle β of the finite element model. i The effect of the three elements S on the structural components, connection nodes and connected building supports i ;

[0028] S22, the displacement angle between each layer β i The inter-story displacement limit [β] is compared with the corresponding code requirements, and the effect S of the three elements of structural members, connection nodes and connected building supports is calculated. i Compare with the corresponding structural resistance R respectively; if β i ≤[β] and S i ≤R, it indicates that the deformation and bearing capacity of the finite element model meet the requirements of the specification, and jump to step S3; otherwise, go to step S23;

[0029] S23, optimize and adjust the finite element model, and then return to step S21 until β is satisfied. i ≤[β] and S i ≤R.

[0030] Further, step S6 includes:

[0031] S61, if i 1.i <[R] and R 2.i <[R], [R] is the bearing capacity limit of the connected building support, then the reaction force of the connected building support meets the safety requirements; otherwise, the support of the connected building is replaced with a support with higher safety;

[0032] S62. If α1<[α] and α2<[α], [α] is the comfort acceleration limit specified in the specification, it means that the comfort of the connected structure meets the requirements, otherwise strengthening measures need to be taken;

[0033] S63. If the finite element model is adjusted in step S61 or S62, the process returns to step S3 until the reaction force and comfort level of the connected building support meet the requirements.

[0034] Furthermore, in step S23, the method of optimizing and adjusting the finite element model includes adjusting component size, changing the single tower structure or connection form.

[0035] Furthermore, in step S43, the method for selecting the most unfavorable wind direction angle is: according to the results of the structural base shear force, base bending moment and tower top floor displacement response under the action of the average wind in all wind directions, the most unfavorable wind direction angle is determined, and 3-10 most unfavorable wind direction angles are selected.

[0036] Furthermore, in step S62, the strengthening measures are increasing the number of vertical components, increasing the cross-sectional dimensions of the vertical components, setting inter-column supports, or setting tuned mass dampers.

[0037] Furthermore, the finite element model includes each single tower and a connector; the connected building support includes a connector support and each single tower support.

[0038] The present invention has the following beneficial effects:

[0039] 1. The present invention provides a wind-resistant design method for a multi-tower connected building. Based on the wind load parameters of the specification, the wind pressure time history of the connected building is simulated and the wind tunnel test structure is used to obtain the wind pressure time history of the connected building, and the maximum shear force V of the two sets of structures is obtained. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i And the mean acceleration α1 data of the connector, and at the same time, the finite element model of the connected building is tested and optimized to ensure the wind resistance of the connected building.

[0040] 2. The present invention provides a wind-resistant design method for a multi-tower connected building, which provides a new method for calculating the maximum shear force of the structural base, structural deformation, the maximum reaction force of the connected building supports, and a comfort verification method. It innovatively converts the node wind pressure time history obtained from the wind tunnel test into a node concentrated load, and proposes a calculation formula. The concentrated load under the most unfavorable wind direction angle is then applied to the corresponding node of the finite element model to perform a wind-vibration response time history analysis, thereby improving the calculation accuracy of the wind load effect and the comfort verification accuracy of the connected buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The present invention is a flow chart of the wind-resistant design method. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] like Figure 1 As shown, the present invention provides a wind-resistant design method for a multi-tower connected building, comprising the following steps:

[0044] S1. Establish a finite element model of the connected building structure, which includes each single tower and the connector;

[0045] S2, optimize the finite element model;

[0046] S21. Perform structural stress analysis on the finite element model under equivalent static wind load to obtain the inter-layer displacement angle β of the finite element model. iThe effect of the three elements S on the structural components, connection nodes and connected building supports i ; The connected building supports include the connector supports and the supports of each single tower;

[0047] S22, the displacement angle between each layer β i The inter-story displacement limit [β] is compared with the corresponding code requirements, and the effect S of the three elements of structural members, connection nodes and connected building supports is calculated. i Compare with the corresponding structural resistance R respectively; if β i ≤[β] and S i ≤R, it indicates that the deformation and bearing capacity of the finite element model meet the requirements of the specification, and jump to step S3; otherwise, go to step S23;

[0048] S23, optimize and adjust the finite element model, the optimization method may be to adjust the component size, change the single tower structure system or connection form, etc.; then return to step S21 until β is satisfied. i ≤[β] and S i ≤R;

[0049] S3. Based on the wind load parameters of the specification, the wind pressure time history of the connected building is simulated, and the dynamic analysis and comfort analysis of the finite element model are performed to obtain the maximum shear force V of the structural base. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i and the mean acceleration of the connector α1;

[0050] S31. The wind pressure time history of the connected building is obtained by using the wind pressure time history simulation method. The wind pressure time history of each floor of each tower is applied to the corresponding floor gravity center position, and the wind vibration response time history analysis of the structure is performed. The maximum shear force V of the structure base is obtained by dynamic calculation. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i ;

[0051] S32. Using the wind pressure time history with a return period of 10 years, the finite element model is subjected to a wind-induced vibration response time history analysis to obtain the acceleration time history response of each point of the connector and the average acceleration α1 of the connector;

[0052] S4. Based on the wind tunnel test structure, the wind pressure coefficient time history of the connected building is obtained, and the dynamic analysis and comfort analysis of the finite element model are performed to obtain the maximum shear force V of the structural base. 2.max , structural deformation, maximum reaction force R of the connected building support 2.i and the mean acceleration of the connected body, α2;

[0053] S41. Perform a scaled model wind tunnel test on the connected building, and obtain the wind pressure coefficient time history of each node at each wind direction angle of the connected building according to the wind tunnel test results; specifically, during the wind tunnel test, the wind pressure at each measuring point at each time is measured by a wind pressure sensor, and the ratio of the wind pressure at each measuring point at each time to the wind pressure at a reference point (generally, a position that is not affected by the building model and the wind tunnel wall is selected as the test reference point) is used as the dimensionless wind pressure coefficient, and the curve of the change of this dimensionless coefficient over time is the wind pressure coefficient time history;

[0054] S42. Convert the wind pressure coefficient time history of the node into the concentrated load of the node. The calculation formula is:

[0055] p j (t) = w0μ z A j C P,j (t);

[0056] Among them, p j (t) is the concentrated load of the jth node at time t; ω0 is the basic wind pressure; μ z A is the wind pressure height coefficient at the wind pressure reference point; j is the wind-affected area of ​​the jth node; C p,j (t) is the wind pressure coefficient of the jth node at time t;

[0057] S43, selecting the most unfavorable wind direction angle; judging the most unfavorable wind direction angle according to the response results of the structural base shear force, base bending moment (torque) and tower top floor displacement under the action of the average wind in all wind directions, preferably, selecting 3-10 most unfavorable wind direction angles;

[0058] S44. Apply the concentrated load under the most unfavorable wind direction angle to the corresponding nodes of the finite element model, and use Midas Gen finite element analysis software to perform wind-induced vibration response time history analysis;

[0059] S45. The maximum shear force V of the structural base is obtained through dynamic calculation 2.max , structural deformation, maximum reaction force R of the connected building support 2.i ;

[0060] S46, according to step S44, obtaining the acceleration time history response of each point of the connector under the most unfavorable wind direction angle and the average acceleration α2 of the connector;

[0061] S5. Adjust the internal force parameters of the finite element model. The adjustment coefficient of the base shear force is π, π=max(V 1.max , V 2.max) / V0, V0 is the initial base shear value of the finite element model obtained in step S2; when π≤1, π=1 is taken, and there is no need to adjust the internal force parameters; after adjustment, re-verify whether the deformation and bearing capacity of the finite element model meet the requirements of the specification, and the verification method is the same as step S2; the adjustment method can be to adjust the size of the component, change the single tower structure system and the connection form, etc.;

[0062] S6: The maximum value R of the structural deformation and the reaction force of the connected building support obtained twice in steps S3 and S4 1.i , R 2.i and the mean accelerations α1 and α2 of the connectors to assess the safety and comfort of the connected buildings;

[0063] S61, if R 1.i <[R] and R 2.i <[R], [R] is the bearing capacity limit of the connected building, then the support reaction of the connected building meets the safety requirements; otherwise, the support of the connected building is replaced with a support with higher safety;

[0064] S62. If α1<[α] and α2<[α], [α] is the comfort acceleration limit specified in the code, it means that the comfort level of the connected building meets the requirements. Otherwise, strengthening measures need to be taken, including increasing the number of vertical components, increasing the cross-sectional dimensions of vertical components, setting column supports or setting tuned mass dampers, etc.;

[0065] S63. If the finite element model is adjusted in step S61 or S62, the process returns to step S3 until the reaction force and comfort level of the connected building support meet the requirements.

[0066] Among them, in step S31, the wind pressure time history simulation method is: according to the standard wind pressure, ground roughness category, body coefficient and calculated floor height, the wind pressure time history of each floor of each tower of the connected building is simulated by time domain analysis method.

[0067] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wind-resistant design method for a multi-tower connected building, characterized in that: The following steps are involved: S1. Establish a finite element model of the connected building structure; S2. Optimize the finite element model so that the interlayer displacement angle β of the finite element model i The inter-story displacement limit [β] specified in the corresponding code shall not be exceeded, and the effectiveness of the three effects of structural members, connection nodes and connected building supports S i Not exceeding the corresponding structural resistance R; S3. Based on the wind load parameters of the specification, the wind pressure time history of the connected building is simulated, and the dynamic analysis and comfort analysis of the finite element model are performed to obtain the maximum shear force V of the structural base. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i and the mean acceleration of the connected body α1; S4. Based on the wind tunnel test structure, the wind pressure coefficient time history of the connected building is obtained, and the dynamic analysis and comfort analysis of the finite element model are performed to obtain the maximum shear force V of the structural base. 2.max , structural deformation, and the maximum reaction force of the connected building support R2. i and the mean acceleration of the connected body, α2; S5. Adjust the internal force parameters of the finite element model. The adjustment coefficient of the base shear force is π, π=max(V 1.max , V 2.max ) / V0, where V0 is the initial base shear value of the finite element model obtained in step S2; when π≤1, π=1 is taken, and there is no need to adjust the internal force parameters; S6: The maximum value R of the structural deformation and the reaction force of the connected building support obtained twice in steps S3 and S4 1.i , R 2.i and the mean acceleration α1 and α2 of the connector, the safety and comfort of the connected building are evaluated, and the finite element model is adjusted to meet R 1.i <[R] and R 2.i <[R], [R] is the bearing capacity limit of the support of the connected building, and satisfies α1<[α] and α2<[α], [α] is the comfort acceleration limit specified in the code.

2. A wind-resistant design method for a multi-tower connected building according to claim 1, characterized in that: Step S4 includes: S41. Conduct a scaled model wind tunnel test on the connected building, and obtain the wind pressure coefficient time history of each node of the connected building at each wind direction angle according to the wind tunnel test results; S42. Convert the wind pressure coefficient time history of the node into the concentrated load of the node. The calculation formula is: j (t) = w0μ z A j C P，j (t); Among them, p j (t) is the concentrated load of the jth node at time t; ω0 is the basic wind pressure; μ z A is the wind pressure height coefficient at the wind pressure reference point; j is the wind-affected area of ​​the jth node; C p，j (t) is the wind pressure coefficient of the jth node at time t; S43, select the most unfavorable wind direction angle; S44, applying the concentrated load under the most unfavorable wind direction angle to the corresponding nodes of the finite element model, and performing a wind-induced vibration response time history analysis; S45. The maximum shear force V of the structural base is obtained through dynamic calculation 2.max , structural deformation, maximum reaction force R of the connected building support 2.i ; S46. According to step S44, the mean acceleration α2 of the connector under the most unfavorable wind direction angle is obtained.

3. The wind-resistant design method for a multi-tower connected building according to claim 1 is characterized in that: Step S3 includes: S31. The wind pressure time history of the connected building is obtained by using the wind pressure time history simulation method. The wind pressure time history of each floor of each tower is applied to the corresponding floor gravity center position, and the wind vibration response time history analysis of the structure is performed. The maximum shear force V of the structure base is obtained by dynamic calculation. 1.max , structural deformation, maximum reaction force R of the connected building support 1.i ; S32. Use the 10-year return period wind pressure time history to perform wind vibration response time history analysis on the finite element model to obtain the acceleration time history response of each point of the connector and the mean acceleration α1 of the connector.

4. A wind-resistant design method for a multi-tower connected building according to claim 3, characterized in that: In step S31, the wind pressure time history simulation method is: according to the standard wind pressure, ground roughness category, body coefficient and calculated floor height, the wind pressure time history of each floor of each tower of the connected building is simulated by time domain analysis method.

5. The wind-resistant design method for a multi-tower connected building according to claim 1 is characterized in that: Step S2 includes: S21. Perform structural stress analysis on the finite element model under equivalent static wind load to obtain the inter-layer displacement angle β of the finite element model. i The effect of the three elements S on the structural components, connection nodes and connected building supports i ; S22, the displacement angle between each layer β i The inter-story displacement limit [β] is compared with the corresponding code requirements, and the effect S of the three elements of structural members, connection nodes and connected building supports is calculated. i Compare with the corresponding structural resistance R respectively; if β i ≤[β] and S i ≤R, it indicates that the deformation and bearing capacity of the finite element model meet the requirements of the specification, and jump to step S3; otherwise, go to step S23; S23, optimize and adjust the finite element model, and then return to step S21 until β is satisfied. i ≤[β] and S i ≤R.

6. The wind-resistant design method for a multi-tower connected building according to claim 1 is characterized in that: Step S6 includes: S61, if R 1.i <[R] and R 2.i <[R], [R] is the bearing capacity limit of the connected building support, then the reaction force of the connected building support meets the safety requirements; otherwise, the support of the connected building is replaced with a support with higher safety; S62. If α1<[α] and α2<[α], [α] is the comfort acceleration limit specified in the specification, it means that the comfort of the connected structure meets the requirements, otherwise strengthening measures need to be taken; S63. If the finite element model is adjusted in step S61 or S62, the process returns to step S3 until the reaction force and comfort level of the connected building support meet the requirements.

7. The wind-resistant design method for a multi-tower connected building according to claim 5 is characterized in that: In step S23, the method of optimizing and adjusting the finite element model includes adjusting the component size, changing the single tower structure or the connection form.

8. The wind-resistant design method for a multi-tower connected building according to claim 2 is characterized in that: In step S43, the method for selecting the most unfavorable wind direction angle is: according to the results of the structural base shear force, base bending moment and tower top floor displacement response under the action of the average wind in all wind directions, the most unfavorable wind direction angle is determined, and 3-10 most unfavorable wind direction angles are selected.

9. The wind-resistant design method for a multi-tower connected building according to claim 6, characterized in that: In step S62, the strengthening measures are to increase the number of vertical components, increase the cross-sectional dimensions of the vertical components, set up inter-column supports, or set up tuned mass dampers.

10. The wind-resistant design method for a multi-tower connected building according to claim 1, characterized in that: The finite element model includes each single tower and a connector; the connected building support includes a connector support and each single tower support.

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