| Earthquake is a common natural disaster,which not only brings economic losses but also endangers people's lives.With the development of economy and science and technology,many new structural forms are applied to meet the better safety performance and applicability of the structure.As a new form of storage structure,the new semi-underground bungalow of bulk grain has higher grain loading height and larger storage capacity.At the same time,it uses underground low temperature environment to prevent grain deterioration and aging is more conducive to grain storage security,but also saves land resources,alleviates the contradiction of land resources tension,and has a good development prospect.Therefore,this paper takes the second phase of the expansion project of a grain modern logistics center in Tianjin as the background,through the combination of theory and finite element simulation,considering the interaction between bulk material and structure,studies the dynamic response of the bulk grain semi-underground bungalow of the tie rod system under earthquake action.Three types of tie rods are put forward: column support tie rod,steel support reinforcement tie rod and suspender connection tie rod.The modal analysis of semi-underground bungalow structure with three kinds of tie rod shows that the local vibration of column support tie rod is obvious and the stiffness of steel support reinforcement tie rod is improved.The self-vibration characteristics of the full-warehouse and empty-warehouse are further studied.It is found that the self-vibration frequency of the structure is smaller than that of the empty-warehouse,and the fundamental frequency is reduced by 37%.The dynamic response of empty and full silo under the condition of seven-degree earthquake is calculated by means of vibration mode decomposition method and <<Code for design of grain steel silos>>(GB 50322-2011).Comparative analysis shows that the seismic performance of the structure under the two methods is good,the maximum displacement of the structure calculated by the code method is 1.62 times the maximum displacement of the reaction spectrum method.The seismic performance of the structure is designed according to the code calculation,and the structure is biased towards safety.The response of a new type of semi-underground bungalow for bulk grain under single and two-way earthquake was analyzed.The finite element simulation of the existing silo shaking table test is carried out.The validity and rationality of the contact model,material constitutive,element type and so on used in the finite element analysis are confirmed by the comparison of the test results.The coupling of grain and structure,first of all,the interaction between soil and structure is not considered.EL-Centro wave,artificial simulation of waves and Kar wave are selected to analyze the time history of empty warehouse,half warehouse,3/4 warehouse and full warehouse working conditions,respectively.The results show that the top displacement increases with the increase of grain loading height under any seismic wave.structure under the action of EL-Centro waves deformation is the largest,the structure is more prone to resonance.The interaction between food and structure is energy-consuming.Further considering the interaction between soil and structure,the dynamic response under EL-Centro wave is analyzed,and the seismic response of the structure is found to be weakened.The seismic research for semi-underground bunker is less,and there is no mature and perfect specification.In this paper,the modal analysis,reaction spectrum analysis,time-history analysis and related specifications of semi-underground bulk grain bungalow structure are studied.The purpose of this paper is to provide some reference for the design of relevant warehouse type,especially in earthquake resistance. |
PDF Full Text Request