Research On Wind Load And Interference Effect On The Concave Surface Span Structures

The concave surface roof is a special appearance in the long-span structuresshape as a novel appearance, the pressure distribution and interference effects are alsodifferent from the characteristics of other roof. Due to the particularity of such abuilding structure, the pressure distribution and effects in the study is necessary andengineering significance.Taking the stadium of Guizhou Weining Olympic center as the projectbackground in this paper, the system research have been cayyied out and meaningfulresults have been obtained.Firstly, wind tunnel test was carried out with synchronously measured pressureon the rigidity model in two cases, with and without surrounding buildings. As the testdata, the pressure distribution feature on the surface of the concave roof have beenobtained. Along the long span of the roof,the forefront of the long span has a greaternegative pressure, the middle is small negative pressure and away from the directionof the flow pressure coefficient is zero or positive; Along short span of the roof,theforefront of the long span has a large negative pressure, near the lowest point of themiddle concave pressure is zero, far away from the flow direction is positive pressure.Besides it is found that the interference effects of surround buildings iscomplex.When there are buildings in front of the roof, the interference effects for theroof windward is much bigger than other parts of the roof. When there are buildings inback of the roof, the interference effects for the roof leeward is much bigger thanother parts of the roof.Secondly, finite element model was established in finite element programANSYS.Based on the time-history pressure on the key points in wind tunnel test, theactual time-history pressure on the key points were obtained by data conversion andinterpolation and the pressure were loaded into the finite element model.By usingtime domain analysis method,the structure’s wind-induced response wereobtained,the wind-induced response characteristics on the concave surface roof andthe interference of surroundbuildings have been studied.Again, based on the actual time-history pressure on the key points, a generalizedforce spectrum is constructed. Linear systems in stationary random excitation withrandom vibration mode superposition method were used for the preparation of Matlab computing program in calculating the structure of wind-induced dynamic response infrequency-domain. In programming process, the effects of the power spectrum andvibration coupling and the applications make the interference analysis of thesurrounding buildings on the roof wind induced response, and make a comparisonbetween time domain and the frequency-domain procedure. The results show that agood correlation exists in the time domain and frequency domain and the impact ofthe higher modes should be taken into account in frequency domain calculation.Finally, the wind load specifications of the foreign countries and regions havebeen introduced the comparison among them and our country’s specifications hasbeen made. Taking Weining Stadium’s curtain wall as an example, the designing windloads by using different specifications were calculated. The conclusion is that thedesigning wind loads on curtain of each floor is closer to each other. Gust windpressure in our country’s loads specifications and test specification extremumpressure were compared and they are closer to each other,and this validate the extremewind pressure on our country’s specification.