储煤仓三心圆柱面屋盖风荷载及风振特性研究

发布时间：2018-04-05 02:31

本文选题：三心圆柱壳　切入点：开敞方式　出处：《哈尔滨工业大学》2014年硕士论文

【摘要】：大型百米级跨度的储煤仓属典型风敏感结构，风荷载是设计时需要重点考虑的荷载。目前荷载规范中，仅提供全封闭的柱壳体型系数取值建议，而对于实际工程中常用的全开敞及半开敞的煤仓柱壳目前尚没有体型系数等信息可供设计人员参考。本文针对典型三心圆柱壳储煤仓考虑了不同开敞方式及长宽比的影响进行了系列风洞试验，对屋盖风荷载及风振特性进行了系统研究，主要包括：平均及脉动风荷载特性分析，风振响应分析。为进一步的理论分析和实际工程设计提供依据。主要内容如下： 1.设计并进行了系列三心圆储煤仓柱壳刚性模型测压试验，长宽比为1、1.5和2，开敞方式包括了全封闭、全开敞及半开敞等6种不同的方式，地貌为B类。 2.基于风洞试验数据，，研究了储煤仓平均风荷载特性，探讨了开敞方式及长宽比对储煤仓平均风荷载的影响，给出不同开敞方式下的最不利风向角为：全封闭60°、全开敞60°、半开敞30°，及最不利风向角下的分区体型系数取值建议，比较了开敞方式变化对三心圆柱壳屋盖各处风荷载的影响。 3.对储煤仓脉动风荷载及脉动风压功率谱进行了细致的研究，探讨了开敞方式及长宽比对脉动风荷载的影响，给出了适用于维护结构设计的局部体型系数。通过自谱和互谱特性分析，得到了长宽比及开敞方式对脉动风压谱的影响，给出了不同长宽比及开敞方式储煤仓脉动风压自谱及互谱模型。 4.通过建立有限元模型并利用风洞试验得到的风压时程数据进行了风振响应分析，得到了3种长宽比及6种开敞方式的储煤仓共计18种工况，在30°、60°及90°风向角下的风振响应，包括节点位移响应、单元内力响应及支座反力响应，并确定了基于响应的风振系数及等效静风荷载，经过整理得到了可供设计参考的不同长宽比储煤仓风振系数。风振系数根据不同响应取值为：长宽比为1时取值2.5、长宽比为1.5时取值2.8、长宽比为2时取值3.0。
[Abstract]:Large 100 meter span coal storage bunker is a typical wind-sensitive structure, and wind load is the load that should be considered in design.At present, in the load code, only the advice of the fully enclosed cylindrical shell coefficient is provided, but for the fully open and semi-open coal bunker shell, which is commonly used in practical engineering, there is no information such as shape coefficient for designers to refer to at present.In this paper, a series of wind tunnel tests are carried out for typical three-core cylindrical shell coal storage bunkers considering the effects of different open ways and aspect ratio. The wind load and wind-induced vibration characteristics of roof are systematically studied, including the analysis of average and pulsating wind load characteristics.Wind vibration response analysis.It provides the basis for further theoretical analysis and practical engineering design.The main contents are as follows:1.A series of three center circular coal storage bunker shell rigid model pressure measurement tests were designed and carried out. The aspect ratio is 1: 1. 5 and 2. The open mode includes 6 different ways, such as completely closed, fully open and semi-open, and the geomorphology is B.2.Based on the wind tunnel test data, the average wind load characteristics of coal storage bunker are studied, and the effects of open mode and aspect ratio on the average wind load of coal storage bunker are discussed.The most unfavorable wind direction angles under different open modes are as follows: totally closed 60 掳, full open 60 掳, semi-open 30 掳, and the partition shape coefficient under the most unfavorable wind direction angle is suggested, and the influence of the variation of open mode on the wind loads around the three-core cylindrical shell is compared.3.The pulsating wind load and pulsating wind pressure power spectrum of coal storage bunker are studied in detail. The influence of open mode and aspect ratio on pulsating wind load is discussed. The local shape coefficient suitable for the design of maintenance structure is given.The influence of aspect ratio and open mode on fluctuating wind pressure spectrum is obtained by analyzing the characteristics of autospectrum and cross-spectrum. The autospectrum and cross-spectrum model of fluctuating wind pressure in different aspect ratio and open mode are given.4.Based on the finite element model and the wind pressure time history data obtained from wind tunnel test, the wind-induced vibration response of three coal storage bunkers with three aspect / width ratios and six open modes was obtained under 30 掳~ 60 掳and 90 掳wind direction angle.It includes node displacement response, element internal force response and support reaction response, and determines the wind-induced vibration coefficient and equivalent static wind load based on the response.The values of wind-induced vibration coefficient are as follows: when the aspect ratio is 1, the aspect ratio is 2.5, the aspect ratio is 1.5, the value is 2.8, and the aspect ratio is 2, the value is 3.0.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU312.1

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