Structure And Strength Analysis Of Large-Sized Rectangular Coal Bunker

The pressure vessels in the chemical industry are mainly spherical and cylindrical vessels.Rectangular cross-section vessels are rarely used in medium and high-pressure vessels due to their complex mechanical models and poor load-bearing capacity.However,the rectangular container is simple in structure and convenient to manufacture,which makes it more and more widely used in low-pressure containers.Domestic and foreign scholars’ relevant research on Bunkers is mostly theoretical and experimental research on circular Bunkers.Through the establishment of corresponding mechanical models,the analytical solution of the bending stress of the Bunker wall is derived,and the theories are analyzed and compared through experimental research or numerical simulation.The formula calculates the accuracy of the storage material stress in the Bunker.This paper takes the rectangular pulverized coal storage bunker in a certain project as the research object,and uses the advanced research results of the circular storage bunker as the theoretical basis.By modifying the corresponding calculation formula,the storage pressure in the storage bunker is calculated in detail,the structural stability of the Bunker body was analyzed,and finally a structure and strength analysis method suitable for large rectangular pulverized coal storage Bunker was proposed.The specific work and conclusions are as follows:(1)According to the needs of theoretical research,the rectangular Bunker is designed as a structure with two conical funnels directly connected under the rectangular Bunker.The hydraulic radius calculation method is used to calculate the equivalent radius of the Bunker cylinder and the funnel cone to obtain the storage Design parameters of warehouse foundation.(2)Perform theoretical calculations on the static load and dynamic load of the rectangular Bunker.The calculation formulas of horizontal wind force and horizontal seismic force are corrected by the body shape factor and the frame magnification factor;the concentrated mass method and the bottom shear force method are used to calculate the wind bending moment and seismic bending moment of the rectangular storage.According to the calculation results,the load value of the cross section at different positions is related to the distance from the cross section to the reference cross section.Multiple calculated cross sections are divided on the Bunker cylinder to obtain the corresponding load value.(3)Calculate the storage pressure of rectangular shell and conical shell.The Reimbret theory is used to calculate the combined tensile and compressive stresses of the Bunker body and the cone shell.The results show that the various stress levels are controlled within the allowable stress range.Among them,the combined compressive stress design margin is relatively small,which is the design control factor.(4)Compare and analyze the calculation results of Reimbret theory and Janssen theory.The results show that the various forces obtained according to the Reimbret theory are significantly greater than the results calculated by the Janssen formula.The minimum deviation between the two is 20.94% and the maximum deviation is 45.1%.The result shows that Reimbret theory is a modified version of Janssen theory,and the mechanical model established by it is more in line with the actual force of the Bunker.(5)Research on the structural stability of the Bunker,conduct vertical and horizontal joint reinforcement of the Bunker wall,calculate and check the rectangular Bunker’s performance based on the Navier solution that simply supports four sides and bears triangular or trapezoidal loads.The strength and rigidity of the wall panels,top panels and top edge reinforcements meet the requirements of the specifications.(6)Use the finite element analysis software ANSYS to establish a numerical calculation model for the overall structure and support of the rectangular Bunker,and check the strength and stiffness of the support.The results show that the film stress of the support is mainly concentrated on the part supported by the weighing instrument,the film and bending stress of the support is mainly concentrated on the middle angle steel welded to the short wall plate.The deformation of the support is mainly distributed on the middle angle steel welded with the short wall plate,the right-angle connection of the bottom plate and the middle position of the long side of the bottom plate.According to the analysis results,the maximum displacement of the support structure is less than its allowable deflection value,which meets the rigidity requirements.