Experimental Research On Mechanical Properties Of A New Double-Wall Fabricated Steel Insulation Silo With Multiple Bolted Joints

As the main tool of food storage, the silo plays an important role in grain storage. And it is morewidely used since introduced into china in the mid-20th century. However, due to the short period offifty years development, many aspects are not mature enough, yet to be further in-depth research.First, a double-wall steel silo unloading test is carried out in accordance with establishedunloading ways, and sum up the characteristics and principles of the ways of discharging by observingand analyzing the experimental phenomenon. Next, the experimental data is analyzed to obtain thedistribution and the dynamic characteristics of the pressure of each mode in the process of dischargingon the inner wall of the silo. Then, the accuracy of the load plan is verified by comparing themeasured values and theoretical calculating values and the mechanical properties of the silo under theaction of each load form preliminary is studied by analyzing analysis result of ANSYS. Finally, thesimplified designs of silo model under the action of each typical load separately is researched byanalyzing and summarizing the results of the tests, the results of simulation analysis of ANSYS andthe related studying achievement of the our research group.The main research contents and conclusions of this paper are as follows:(1) The bulk solid remained in the silo after the tests of symmetry discharge is symmetrical in acharacteristic way; while the bulk solid remained in the silo after the tests of eccentricity discharge isunsymmetrical in a characteristic way.(2) Define the time from the bearing arch is formed to it is destroyed as a period, it repeats untilthe discharge is done. Besides, there are both mass flow and funnel flow in the process of thedischarge, it’s likely to have dynamic characteristics at the junction of mass flow and funnel flow.(3) The pressures of measuring points at the same height are no different in the process ofsymmetrical discharge, while eccentric discharges are quite different. Whether symmetrical oreccentric discharge process, the distribution of inner plate′s side pressure appeared to linear along theheight.(4) The side pressure dynamic characteristic of the double-walled silo does not appear obviouslyat the beginning of discharge. While there is a certain dynamic characteristic in the discharge progress.Considering the overall trend and local oscillation, the dynamic characteristic of eccentric discharge ismore obvious than symmetric discharge, and it is enhanced in the order of point discharge, linedischarge and surface discharge. (5) The eccentric discharge load mode proposed in this paper has a certain degree of reliability.The calculating reliability of the load mode successively improved in the order of point eccentricdischarge, line eccentric discharge and surface eccentric discharge.(6) The maximum stress of the inner and outer plate under eccentric loads is higher than thestress of symmetrical loads, but the increase is no more than25%. The stress of the inner and outerplate at the most unfavourable moment increases in turn of point, line, and surface eccentric dischargeloads.(7) The simplified design method proposed in this paper for double-walled silos has a certaindegree of reliability. While there is some difference between the finite element simulation results andthe simplified design results, and the simplified method is conservative.This work is supported by national natural science foundation51008067, the six personnel peaksupport plan of Jiangsu province2010-JZ-007, urban and rural hosing and the ministry of constructionscience and technology2011-K1-68. All these supports are greatly acknowledged.