（同濟大學土木工程防災國家重點實驗室，上海 200092）

[摘要]  Jensen數(shù)（屋面高度h與地面粗糙度長度z₀之比）對低矮建筑屋面和墻面風壓有較大影響?；谕瑵髮W浦東實測基地的某低矮建筑，建立了風洞試驗和數(shù)值模擬模型，通過改變模型尺寸和地面粗糙度長度，用風洞試驗和數(shù)值模擬方法詳細研究了Jensen數(shù)對低矮建筑屋面和墻面風壓的影響。結(jié)果發(fā)現(xiàn)對于30°坡角低矮房屋正面迎風時：迎風墻面上正風壓基本與Jensen數(shù)無關(guān)；背風墻面和背風屋面上的負風壓隨著Jensen數(shù)的增大而增大；迎風屋面上檐口處負風壓隨著Jensen數(shù)的增大而增大，中間及靠近屋脊處的正風壓隨著Jensen數(shù)的增大而減小。這些結(jié)論對低矮房屋風洞試驗和數(shù)值模擬都有一定的參考價值。

[關(guān)鍵詞]  Jensen數(shù)；低矮房屋；風荷載；風洞試驗；數(shù)值模擬

中圖分類號：TU312.1

Experimental study and numerical simulation of the Jensen Number on

wind loads of low-rise buildings

Zheng Jianjian, Huang Peng, Gu Ming

(State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China)

Abstract: The Jensen Number, defined as the ratio of building model height to aerodynamic roughness length, has great impact on wind loads of low-rise buildings’ roofs and walls. Based on a full-scale low-rise building in the field laboratory of Tongji University near Shanghai Pudong International Airport by the East China Sea, the methods of wind tunnel test and numerical simulation are employed, with modifying and adjusting the model sizes and aerodynamic roughness lengths, to study the Jensen Number effects on wind loads of roofs and walls of a low-rise building with a 30° pitch gable roof. When the wind blows normally to the building, the results show that: 1) the Jensen Number has little effects on positive shape coefficients of wind load of windward wall; 2)The absolute values of the negative shape coefficients of wind load of leeward wall and roof increase with the rising Jensen Number; 3) As the Jensen Number rises, the absolute values of negative shape coefficients of wind load of the eave of the windward roof increases, while the positive shape coefficients of wind load in the middle of windward roof or near the ridge drop with the growing Jensen Number. These results offer some academic significance to wind tunnel tests and numerical simulations of low-rise buildings.

Keywords: the Jensen Number; low-rise building; wind load; wind tunnel test; numerical simulation

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