| Since the beginning of the 20 th century,the speed of urbanization of human society has been accelerating,and a large number of people have flooded into the cities.In order to meet the housing requirements of the newly added population of the city,high-rise buildings have been used,and then they have ushered in rapid development.The development of high-rise buildings depends on the strength of building materials and advanced construction techniques.Therefore,with the continuous advancement of materials science,more and more new materials have been applied to the construction field.With the replacement of manual work by large machinery,the height of high-rise buildings has been increasing and it has begun to develop to super high-rise.As the height of the building increases,the impact of wind loads on the building becomes more and more obvious.In the field of super high-rise buildings,wind loads have become one of the main loads affecting the building structure.However,due to the large randomness of wind generation and the complicated flow state,it is difficult to calculate with a unified formula in practical engineering.At present,more wind tunnel test methods using scale models are used.However,this method has high experimental cost,high technical difficulty,and long test period.In order to solve such problems,the researchers used the powerful computing function of the computer,combined with the basic theory of fluid mechanics and numerical calculation,established a numerical wind tunnel model,and used numerical calculation methods to study the wind load effect of super high-rise buildings,and achieved numerous Research results.Numerical simulation has been widely used because of its high efficiency,accuracy and low cost.In this paper,the computational fluid dynamics numerical simulation technology is used to calculate the wind load effect of super high-rise buildings.The numerical simulation results are used to study the wind load effect.Firstly,the CAARC high-rise building standard model is numerically simulated by different turbulence models.The obtained results are compared with the experimental data of the CAARC high-rise building standard model.The turbulence model with higher precision is selected,and the turbulence model is used for the next numerical simulation.among.Then,for the super high-rise buildings with 3×3 beam structure,7 different income modes were designed.Using the previously determined turbulence model,the numerical simulation of the seven high-rise buildings with different income modes will be carried out.The results were compared to analyze the surface wind pressure distribution of the super-tall buildings with different loading modes under the wind load,the distribution of the flow field around the building,the base shear force and the bending moment.Through the comparative analysis of the numerical simulation results,the following conclusions are drawn: When the incoming flow has no turbulent flow,the Realizable k-ε model and the SST k-ω model simulate the symmetry of the wind pressure on the side of the building and the leeward side.The results calculated using the RNG k-ε model show that the symmetry of the wind pressure on the building surface is poor.When there is turbulence in the incoming flow,the calculation result of the SST k-ω model has less error with the measured results of the CAARC model,and the wind pressure error is basically within 10%.Therefore,the SST k-ω model was used for simulation in subsequent simulations.It can be seen from the average wind pressure contour map of each surface of the building model that the peak value of the building’s positive wind pressure is mainly located in the upper part of the windward side of the building,while the peak of the negative wind pressure is mainly located at the corner of the side of the building,and the income is uniform.The negative pressure of the building on the top side of the building is greater than that of the non-uniformly received building;according to the flow field around the building,when the upper part of the building is large,the area near the leeward side of the building forms two larger The vortex makes the leeward side subject to suction.When the upper part of the building is small,a vortex is formed mainly in the middle and lower part of the building.According to the values of the base shear force and bending moment in all directions of the building,the wind load effect of the super high-rise building is affected.The wind direction has a great influence.Therefore,in the initial selection of super high-rise buildings,it is necessary to combine the local wind direction rose diagram to analyze the wind direction distribution of the area.If the wind direction is relatively simple or the proportion of a certain wind direction is large,the way of collecting the super high-rise buildings at this time can choose a more complicated way of collecting,but the volume of the upper part of the building should be reduced and the height difference of each beam should not be exceeded.Large;if the local wind direction distribution is more complicated,the collection method of super high-rise buildings should adopt a more symmetrical and regular collection method.It is also necessary to pay attention to appropriately reducing the upper volume of the building and the height difference between adjacent bundles should not be too large. |
