Experimental study of transition junctions in elevated steel silos

Abstract

用于散料储存的大型高架式钢筒仓结构通常由仓筒、锥形漏斗以及支承裙筒组成。在漏斗壁拉力水平分力的作用下 ,漏斗 -仓筒 -裙筒连接处产生相当大的周向压力 ,通常通过设置环梁以增加其强度。转折连接的主要破坏模式包括塑性破坏及环梁的弹性或塑性屈曲。国际上对这类连接的屈曲及破坏强度已有了大量的理论研究 ,并建立了基于理论的设计建议 ,但其试验研究尚属空白。本文总结了作者针对钢筒仓转折连接的稳定与强度问题近期在香港理工大学进行的一项大型试验研究项目。首先简单介绍该项目所建立的一套用于薄壳结构屈曲试验的试验装置 ,然后给出三个系列试验 (内压下的圆锥 -圆柱筒连接、散料荷载下的漏斗 -仓筒 -裙筒连接及散料荷载下的漏斗 -仓筒 -裙筒 -环梁连接 )的主要试验结果。 Large elevated steel silos for the storage of bulk solids generally consist of a cylindrical vessel,a conical discharge hopper and a skirt.The cone-cylinder-skirt junction is subject to a large circumferential compressive force which is derived from the horizontal component of the meridional tension in the hopper,so a ring is often provided to strengthen the junction.The strength of the junction may be limited by plastic collapse of the junction or by elastic or plastic buckling of the ring.Internationally,many theoretical studies have examined the buckling and collapse strengths of these junctions and theoretically based design proposals have been setablished,but no previous experimental study has been reported.This paper provides a summary of a major experimental program recently undertaken at The Hong Kong Polytechnic University on the buckling and collapse of steel silo transition junctions.A sophisticated experimental facility which can be used for buckling experiments on thin shell structures is first briefly described.Then,typical results of three series of tests on cone-cylinder junctions under internal pressure,cone-cylinder-skirt junctions under bulk solid loading and cone-cylinder-skirt-ring junctions under bulk solid loading are reported.