Research On Seismic Performance Of Multi-layer Modular Box Houses

The modular box house is a movable,reusable building product.As the earliest and most representative type of structural form in modular box houses,the container house has many advantages such as low cost,high strength and high assembly.Such significant preponderance will contribute to the in-depth implementation of Chinese building industrialization,standardization and assembly policies.However,as far as the current form of development is concerned,the research on container houses mostly stays at the architecture level or only for a single box.Most of the existing modular container houses are still low-rise houses.Researches on the structure system of multi-layer modular box houses show a lack of corresponding theoretical research and engineering practice.In order to explore the seismic performance of multi-layer modular container houses,the application range of containers is extended from low-level to multi-level and high-rise.Based on the transformation design and simplified numerical simulation of single container box,this paper combined the simulation results of shear performance of containers connection nodes to establish the overall simplified model of multi-layer modular container house by Abaqus and carry out the corresponding frequent earthquake and rare earthquake analysis.The main contents and conclusions of this paper are stated as follows:1.In order to improve the residential comfort,standardization rate and bearing capacity of container houses,the standard 20 ft container was modified to meet the optimization goal,and a new basic unit of box house was proposed.The finite element analysis was carried out and compared with the test results to verify the correctness of the finite element model.Then,the corrugated end plates and the side plates were separately punched to analyze the influence of the hole on its mechanical performance.In order to improve the modeling and analysis rate of the multi-layer modular box house,the beam unit and the equivalent spring cross support were used to simplify the simulation of the modified box and compare with the original model,and an accurate simplified simulation method of the box is obtained.The research results showed that the simulation of the container with the shell element and the solid element had sufficient accuracy and reliability.The simplified simulation of the container box by the beam element and the equivalent cross spring support could simulate its mechanical behavior of the corrugated board better in the elasto-plasticity range;2.The advantages and disadvantages of the commonly used connecting nodes of the container and the scope of application were analyzed.The numerical simulation analysis was carried out on the bearing capacity and shear stiffness of the transverse fastener joints and the cross-fastener joints under different stresses."X-shaped" fastener joints was designed and simulated for connecting four adjacent boxes on the outer surface of a multi-storey containerhouse in order to avoid the node "clogging" phenomenon.The above joints were simulated to obtain their shear capacity,shear stiffness and simplified equivalent spring model of the joints were given for subsequent numerical simulation and seismic performance study of the multi-layer modular box house model.3.The finite element software ABAQUS was employed to simulate the complete model and two forms of model with hole of five-layer modular box house,and carried out modal analysis,frequent earthquake and rare earthquake calculation to obtain a form of opening that had less influence on the overall model stiffness.The conclusion can be drawn that the five-layer end panel open-cavity house model meets the requirements of seismic design specifications under the 7th,8th and 9th degree frequent earthquake and 7th degree rare earthquake.The five-layer side panel open-cavity house model can meets the requirements of seismic design specifications under the 7th and 8th frequent earthquake.In order to improve the seismic performance of multi-storey box house system,an embedded composite beam-column system was proposed.The modal analysis,frequent earthquake calculation and rare earthquake analysis with the new system were carried out on the end plate opening model.In comparison,the results show that the new model can significantly improve the seismic performance of the structure under the action of frequent earthquakes and rare earthquakes.