地表粗糙度对高层建筑下击暴流风荷载特性影响的试验研究
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摘要
地表粗糙度对近地层的风场影响很大。为研究下击暴流风场中不同粗糙度地貌上的高层建筑表面风压变化规律,基于冲击射流试验,讨论了地表粗糙度与径向距离不同情况下高层建筑表面风压特性。试验结果表明:建筑迎风面风压极值区的高度随地表粗糙度的增大而逐渐抬升,迎风面正风压系数也随之增大,背风面负风压绝对值随之减小,侧面风压系数受粗糙度影响变化不明显;建筑侧面脉动风压系数随地表粗糙度的增大而增大,而迎风面和背风面的脉动风压系数受粗糙度影响较小。随着径向距离及地表粗糙度的增大,出流强度衰减明显加快,建筑迎风面中下部区域风压系数衰减较大,背风面及侧面风压系数逐渐减小,且背风面呈线性衰减趋势。
Terrain roughness has a great influence on wind field in near-surface layer. Here, to investigate variation laws of wind pressure on surfaces of a high-rise building on different roughness landforms in downburst wind field, based on impact jet tests, the wind pressure characteristics on the high-rise building's surface were discussed under conditions of different terrain roughness and radial distances. The test results showed that with increase in terrain roughness, the height of the wind pressure extreme value area on the building's windward side gradually rises, and the positive wind pressure coefficient on the windward side also increases, while the absolute value of negative wind pressure on the leeward side decreases; terrain roughness affects lateral wind pressure coefficient not obviously; the building's lateral fluctuating wind pressure coefficient increases with increase in terrain roughness, while terrain roughness affects fluctuating wind pressure coefficients on the windward and leeward sides weakly; with increase in radial distance and terrain roughness, outflow intensity attenuation is accelerated apparently, wind pressure coefficient on middle and lower parts of the windward side decays largely, wind pressure coefficients on the leeward side and lateral side gradually decrease, and the former has a linear attenuation trend.
Terrain roughness has a great influence on wind field in near-surface layer. Here, to investigate variation laws of wind pressure on surfaces of a high-rise building on different roughness landforms in downburst wind field, based on impact jet tests, the wind pressure characteristics on the high-rise building's surface were discussed under conditions of different terrain roughness and radial distances. The test results showed that with increase in terrain roughness, the height of the wind pressure extreme value area on the building's windward side gradually rises, and the positive wind pressure coefficient on the windward side also increases, while the absolute value of negative wind pressure on the leeward side decreases; terrain roughness affects lateral wind pressure coefficient not obviously; the building's lateral fluctuating wind pressure coefficient increases with increase in terrain roughness, while terrain roughness affects fluctuating wind pressure coefficients on the windward and leeward sides weakly; with increase in radial distance and terrain roughness, outflow intensity attenuation is accelerated apparently, wind pressure coefficient on middle and lower parts of the windward side decays largely, wind pressure coefficients on the leeward side and lateral side gradually decrease, and the former has a linear attenuation trend.
引文
[1] LETCHFORD C W,MANS C M,CHAY M T.Thunderstorms-their importance in wind engineering (a case for the next generation wind tunnel)[J].Journal of Wind Engineering and Industrial Aerodynamics,2002,90:1415-1433.
[2] HOLMES J D.Modeling of extreme thunderstorm winds for wind loading of structures and risk assessment[C]//Proceedings of 10th International Conference on Wind Engineering.Copenhagen,1999.
[3] LETCHFORD C W,ILLIDGE G.Turbulence and topographic effects in simulated thunderstorm downdrafts by wind tunnel jet[C]//Proceedings of the 10th International Conference on Wind Engineering.Copenhagen,1999.
[4] WOOD G S,KWORK K C S.Physical and numerical modeling of thunderstorm downbursts[C]//Proceedings of the Tenth International Conference on Wind Engineering.Copenhagen,1999.
[5] SENGUPTA A,SARKAR P P.Experimental measurement and numerical simulation of an impinging jet with application to thunderstorm microburst winds[J].Journal of Wind Engineering and Industrial Aerodynamics,2008,96(3):345-365.
[6] MASON M S,WOOD G S,FLETCHER D F.Impinging jet simulation of stationary downburst flow over topography[J].Wind and Structures,2007,10(5):437-462.
[7] MASON M S,WOOD G S,FLETCHER D F.Influence of tilt and surface roughness on the outflow wind field of an impinging jet[J].Wind and Structures,2009,12(3):179-204.
[8] MASON M S,WOOD G S,FLETCHER D F.Numerical simulation of downburst winds[J].Journal of Wind Engineering and Industrial Aerodynamics,2009,97(11/12):523-539.
[9] MASON M S,WOOD G S,FLETCHER D F.Numerical investigation of the influence of topography on simulated downburst wind fields[J].Journal of Wind Engineering and Industrial Aerodynamics,2010,98 (1):21-33.
[10] SENGUPTA A,SARKAR P P.Experimental measurement and numerical simulation of an impinging jet with application to thunderstorm microburst winds[J].Journal of Wind Engineering and Industrial Aerodynamics,2008,96(3):345-365.
[11] 李春祥,刘晨哲,申建红,等.土木工程下击暴流风速数值模拟的研究[J].振动与冲击,2010,9(12):49-54.LI Chunxiang,LIU Chenzhe,SHEN Jianhong,et al.Numerical simulations of downburst wind speeds in civil engineering[J].Journal of Vibration and Shock,2010,29(12):49-54.
[12] 邹鑫,汪之松,李正良.稳态雷暴冲击风风速剖面模型研究[J].振动与冲击,2016,35(15):74-79.ZOU Xin,WANG Zhisong,LI Zhengliang.Study on the wind profile model of steady-state thunderstorm[J].Journal of Vibration and Shock,2016,35(15):74-79.
[13] SENGUPTA A,SARKAR P P,RAJAGOPALAN G.Numerical and physical simulation of thunderstorm downdraft winds and their effects on buildings[C]//Proceedings of the First American Conference in Wind Engineering.Clemson,SC,2001.
[14] CHAY M T,LETCHFORD C W.Pressure distributions on a cube in a simulated thunderstorm downburst-Part a:stationary downburst observations[J].Journal of Wind Engineering and Industrial Aerodynamics,2002,90(7):711-732.
[15] LIN W E,SAVORY E.Large-scale quasi-steady modelling of a downburst out in flow using a slot jet[J].Wind and Structures,2006,9(6):419-440.
[16] 赵杨,曹曙阳,TAMURA Y,等.雷暴冲击风模拟及其荷载的风洞试验研究[J].振动与冲击,2009,28(4):1-3.ZHAO Yang,CAO Shuyang,TAMURA Y,et al.Simulation of downburst and its loads with wind tunnel test[J].Journal of Vibration and Shock,2009,28(4):1-3.
[17] 邹鑫,汪之松,李正良.稳态冲击风作用下高层建筑风荷载特性试验研究[J].湖南大学学报(自然科学版),2016,43(1):29-36.ZOU Xin,WANG Zhisong,LI Zhengliang.Experimental study on the wind load characteristics of high-rise building in stationary downbursts[J].Journal of Hunan University(Natural Sciences),2016,43(1):29-36.
[18] 李宏海.下击暴流时空分布统计与风场特性和结构风荷载实验研究[D].深圳:哈尔滨工业大学,2015.
[19] LETTAU H.Note on aerodynamic roughness-parameter estimation on the basis of roughness-element description[J].Appl Meteorol,1969,8:828-832.
[20] WOOD G S,KWORK K C S,MOTTERAM A N.Physical and numerical modeling of thunderstorm downbursts[J].Journal of Wind Engineering & Industrial Aerodynamics,2001,89(6):535-552.
[21] 吉柏锋,瞿伟廉.下击暴流作用下高层建筑物表面风压分布特性[J].华中科技大学学报(自然科学版),2012,40(9):89-94.JI Baifeng,QU Weilian.Mean wind pressure distribution characteristics on tall building under downburst[J].Journal of Hunan University(Natural Sciences),2012,40(9):89-94.
[2] HOLMES J D.Modeling of extreme thunderstorm winds for wind loading of structures and risk assessment[C]//Proceedings of 10th International Conference on Wind Engineering.Copenhagen,1999.
[3] LETCHFORD C W,ILLIDGE G.Turbulence and topographic effects in simulated thunderstorm downdrafts by wind tunnel jet[C]//Proceedings of the 10th International Conference on Wind Engineering.Copenhagen,1999.
[4] WOOD G S,KWORK K C S.Physical and numerical modeling of thunderstorm downbursts[C]//Proceedings of the Tenth International Conference on Wind Engineering.Copenhagen,1999.
[5] SENGUPTA A,SARKAR P P.Experimental measurement and numerical simulation of an impinging jet with application to thunderstorm microburst winds[J].Journal of Wind Engineering and Industrial Aerodynamics,2008,96(3):345-365.
[6] MASON M S,WOOD G S,FLETCHER D F.Impinging jet simulation of stationary downburst flow over topography[J].Wind and Structures,2007,10(5):437-462.
[7] MASON M S,WOOD G S,FLETCHER D F.Influence of tilt and surface roughness on the outflow wind field of an impinging jet[J].Wind and Structures,2009,12(3):179-204.
[8] MASON M S,WOOD G S,FLETCHER D F.Numerical simulation of downburst winds[J].Journal of Wind Engineering and Industrial Aerodynamics,2009,97(11/12):523-539.
[9] MASON M S,WOOD G S,FLETCHER D F.Numerical investigation of the influence of topography on simulated downburst wind fields[J].Journal of Wind Engineering and Industrial Aerodynamics,2010,98 (1):21-33.
[10] SENGUPTA A,SARKAR P P.Experimental measurement and numerical simulation of an impinging jet with application to thunderstorm microburst winds[J].Journal of Wind Engineering and Industrial Aerodynamics,2008,96(3):345-365.
[11] 李春祥,刘晨哲,申建红,等.土木工程下击暴流风速数值模拟的研究[J].振动与冲击,2010,9(12):49-54.LI Chunxiang,LIU Chenzhe,SHEN Jianhong,et al.Numerical simulations of downburst wind speeds in civil engineering[J].Journal of Vibration and Shock,2010,29(12):49-54.
[12] 邹鑫,汪之松,李正良.稳态雷暴冲击风风速剖面模型研究[J].振动与冲击,2016,35(15):74-79.ZOU Xin,WANG Zhisong,LI Zhengliang.Study on the wind profile model of steady-state thunderstorm[J].Journal of Vibration and Shock,2016,35(15):74-79.
[13] SENGUPTA A,SARKAR P P,RAJAGOPALAN G.Numerical and physical simulation of thunderstorm downdraft winds and their effects on buildings[C]//Proceedings of the First American Conference in Wind Engineering.Clemson,SC,2001.
[14] CHAY M T,LETCHFORD C W.Pressure distributions on a cube in a simulated thunderstorm downburst-Part a:stationary downburst observations[J].Journal of Wind Engineering and Industrial Aerodynamics,2002,90(7):711-732.
[15] LIN W E,SAVORY E.Large-scale quasi-steady modelling of a downburst out in flow using a slot jet[J].Wind and Structures,2006,9(6):419-440.
[16] 赵杨,曹曙阳,TAMURA Y,等.雷暴冲击风模拟及其荷载的风洞试验研究[J].振动与冲击,2009,28(4):1-3.ZHAO Yang,CAO Shuyang,TAMURA Y,et al.Simulation of downburst and its loads with wind tunnel test[J].Journal of Vibration and Shock,2009,28(4):1-3.
[17] 邹鑫,汪之松,李正良.稳态冲击风作用下高层建筑风荷载特性试验研究[J].湖南大学学报(自然科学版),2016,43(1):29-36.ZOU Xin,WANG Zhisong,LI Zhengliang.Experimental study on the wind load characteristics of high-rise building in stationary downbursts[J].Journal of Hunan University(Natural Sciences),2016,43(1):29-36.
[18] 李宏海.下击暴流时空分布统计与风场特性和结构风荷载实验研究[D].深圳:哈尔滨工业大学,2015.
[19] LETTAU H.Note on aerodynamic roughness-parameter estimation on the basis of roughness-element description[J].Appl Meteorol,1969,8:828-832.
[20] WOOD G S,KWORK K C S,MOTTERAM A N.Physical and numerical modeling of thunderstorm downbursts[J].Journal of Wind Engineering & Industrial Aerodynamics,2001,89(6):535-552.
[21] 吉柏锋,瞿伟廉.下击暴流作用下高层建筑物表面风压分布特性[J].华中科技大学学报(自然科学版),2012,40(9):89-94.JI Baifeng,QU Weilian.Mean wind pressure distribution characteristics on tall building under downburst[J].Journal of Hunan University(Natural Sciences),2012,40(9):89-94.