Research On The Stability And Deformation Monitoring Of The Dense Channels Accessing-sorting Racks System

With the present background "internet+", the sudden rising e-commerce surpassed well beyond the traditional logistics at dynamics, works scale and data scale. With the increasing of logistics flow, rising of storage cost and growing of e-commerce logistics order, the logistics storage is facing the severe situation. Under this circumstance, an effective storage and sorting integration system with racking shuttle technology and intensive racking technology-the dense channels accessing-sorting system (DCASS) is becoming the wide used storage system for present e-commerce logistics center. This pushed the fast growth of the requirements for the intensive storage racking. Under the normal situation, racking has stronger stability and can keep the balance of the outer force and inner force when bearing products. When racking has defects, products are at unreasonable position or the sudden impact will make the racking buckling, and make the elements or the overall racking in an unsteady situation, the geometry structure will change with being lost its working ability and forming storage safety accidents finally. Therefore, the stability issues of racking structure are becoming the hottest researches.The stability of the components and the whole structure based on the DCASS racking system that widely used in the field of the e-commerce logistics are analyzed in the thesis. The FEA simulation analysis and comparesion analysis with Matlab and ANSYS to explore the stability of racking system based on mechanical properties are made. The dynamic deformation monitoring experiment using DCRP technology with the contemporary operation of several racking shuttles, to verify the structure stability and measure the deformation amplitude of the racking system are conducted. The main contents and achievements of the thesis are as followed:(1) Based on the home and abroad researches review on the DCASS technology, the stability of the racking structure and its components and the deformation monitoring technology for the DCASS racking system, the stability of the components and the overall racking structure are analyzed and researched by constructing the DCASS racking system structure model. And also the calculation methods to solve the critical buckling load of the bending buckling, torsional buckling, lateral-torsional bucking and the distortional buckling of the racking system are deduced. The effective width calculation methods of the local buckling are explored and the elastic deformation characteristics are verified by the deformation monitoring experiment to the racking columns.(2) Based on the analysis of the overall stability and instability forms, the symmetrical buckling, anti-symmetrical buckling and elastic buckling of the racking are researched. And the fundamental natural vibration period and the kinematics characteristics of the racking shuttle are researched; the buckling load calculation method of the DCASS racking system with the running racking shuttles on it are explored. By conducting the vibration deformation destructive experiment of the racking system, the thesis explore the mechanism and monitoring methods of steel structure racking from the elastic buckling to elastoplasticity, and to plastic deformation. And some measures to prevent the overall deformation buckling of the racking system are given.(3) Based on the the principle research on the FEA method, the distribution characteristics of the shear force, bending moment and axial force of the racking upright and beam are studied by the Matlab program of the single row DCASS racking. And also the intensity and stiffness weakness parts of the racking system are explored. The buckling characteristics of the structure and its components under the multiple loading status simulation based on the ANSYS racking three-dimension simulation model are researched. By the comparesion of the Matlab operation results and the ANSYS simulation data, to find the weakness part and raise the suggestion of strengthening the stability of the racking.(4) Based on system deformation, deformation analysis and deformation monitoring theory, the multivariate regression analysis model, the gray system GM model and KALMAN FILTER model are researched. Based on the digital camera calibration distortion revising model, the plane pseudo-parallax model and the space pseudo-parallax model, the instantaneous dyamic deformation monitoring experiment is conducted on the DCASS racking system with the racking shuttle normal working status by using DCRP technology. Photos are taken real time, and computer software is operated to draw the racking load-deformation curving chart. By monitoring the overall deformation of the racking and measuring the deformation amplitude to precast the abnormal deformation part of the racking, one can provide the references to verify the stability and the safety forecast of racking system.The thesis makes theory researches, simulation analysis and testing the stability of DCASS racking system to explore the instantaneous dynamic deformation monitoring the racking system with appling the DCRP technology. This not only can protect the safety of storage logistics, but also can make up the blank of the instantaneous dynamic deformation monitoring theory for racking system, as well as can provide the guidance of dynamic deformation monitoring. The research has the important theoretical significance and practical reference value.