【摘要】：筒倉是一種用來儲存各種散體材料的筒狀構筑物。由于其具有占地面積少、倉容量大、使用方便等優(yōu)點,故在糧食,建筑、煤炭、水泥等行業(yè)被廣泛應用。近幾十年來,隨著經濟建設的發(fā)展,國內筒倉數量越來越多。在筒倉結構設計中,選取正確的貯料壓力值是保證筒倉安全可靠的前提�，F今,國內外筒倉規(guī)范對于貯料壓力的計算都是以Janssen公式為基礎的,但大量事實表明利用該公式得到的結果與實際情況有較大的出路。故選取合適的方法對筒倉貯料壓力進行深入的研究很有必要。 到目前為止,國內外大量學者就這一問題進行了分析和研究,但由于散體材料自身的復雜性,使得筒倉貯料壓力理論在很多地方難達到共識,從而導致大量的筒倉事故發(fā)生。 本文以武漢青山區(qū)“7.9”筒倉倒塌事故為背景,采用試驗研究、理論分析和數值模擬相結合的方法,對筒倉各工況下的貯料壓力進行研究,同時將結果運用到事故筒倉,對其進行事故分析,具體工作包括： 1.對筒倉進行了模型試驗研究,得出筒倉在靜止及卸料時的倉壁側壓力,并與規(guī)范結果進行對比發(fā)現利用規(guī)范計算得到的貯料壓力值要比實際情況小。 2.在考慮筒倉內貯料產生土拱效應的基礎上建立了筒倉貯料壓力的計算公式；通過與試驗數據及模擬結果對比,驗證了該公式的正確性。 3.采用離散元軟件對筒倉靜止及卸料時的貯料壓力進行了模擬,得到了筒倉在各工況下的壓力分布規(guī)律,同時分析了各個參數對側壓力的影響。 4.通過觀察筒倉卸料時顆粒的流動,得出貯料在卸料時由于流型轉變而產生的散體拱是造成卸料超壓的主要原因,同時由于貯料流動時的結拱-破拱導致筒倉卸料時倉壁側壓力會不斷的上下波動。 5.對筒倉卸料時的模擬發(fā)現當筒倉孔球徑比達到6.0左右是會出現閉塞現象,同時內摩擦系數越大越易發(fā)生卸料閉塞。 6.將離散元模擬與有限元分析相結合能很好的對筒倉進行結構研究,這樣得出的結果將比以往分析方法更加精確,能為今后的筒倉設計提供新的思路。
[Abstract]:Silo is a cylindrical structure used to store all kinds of bulk materials. Because of its small area, large warehouse capacity, easy to use and other advantages, it is widely used in grain, construction, coal, cement and other industries. In recent decades, with the development of economic construction, the number of silos in China is increasing. In the structural design of silo, selecting the correct storage pressure value is the premise to ensure the safety and reliability of silo. Nowadays, the calculation of storage pressure in silo code at home and abroad is based on Janssen formula, but a large number of facts show that the results obtained by this formula have a great way out with the actual situation. Therefore, it is necessary to select the appropriate method to study the silo storage pressure. Up to now, a large number of scholars at home and abroad have analyzed and studied this problem, but because of the complexity of bulk materials themselves, it is difficult to reach a consensus on silo pressure theory in many places, which leads to a large number of silo accidents. Based on the collapse accident of "7.9" silo in Qingshan District of Wuhan, this paper studies the storage pressure of silo under various working conditions by means of experimental research, theoretical analysis and numerical simulation. At the same time, the results are applied to the accident silo and the accident analysis is carried out. The concrete work includes: 1. The model test of the silo is carried out, and the side pressure of the silo wall is obtained when the silo is static and unloaded, and compared with the code results, it is found that the storage pressure calculated by the code is smaller than the actual situation. two銆，

本文編號：2506065