Study On Mechanics And Waterproof Performance Of Four-chamber Prefabricated Pipe Gallery With Transverse Joints

In order to meet the size and weight restrictions of the prefabricated pipe gallery components for transportation,it is required that the large-section prefabricated integrated pipe gallery needs to be divided into longitudinal and transverse sections.In this paper,a rigid horizontal connection form with simple construction process is proposed.The connection form of the “epoxy rubber bonding and steel plate welding” is used to connect the corridors horizontally to meet the requirements of prefabrication assembly and transportation.That is,the concrete joint surfaces of the horizontal joints of the upper and lower half joints are bonded by epoxy glue,and the sides of each web are welded by the pre-embedded steel plates to form a whole frame.Based on a prefabricated integrated pipe gallery project,this paper proposes two types of joints,I-shaped steel joint and ring-shaped joint.According to the design pattern of the four-chamber,the reinforcement calculation is carried out according to the relevant design specifications.Through ABAQUS,a nonlinear finite element calculation software,and the on-site full-scale model test,the related mechanics and waterproof performance of the large-section multi-chamber prefabricated integrated pipe gallery structure with transverse joints are studied.The purpose is to verify the feasibility of the transverse joint by verifying the reliability of the mechanical properties and waterproof performance of the transverse joint frame.The analysis of the influence of the transverse joint on the mechanical properties of the frame shows that:(1)The gallery with I-shaped steel joints and the gallery with ring-shaped joints meet the requirements of the code for the limit state of normal use and the bearing capacity.(2)The presence of the transverse joint causes cracks in the concrete at the joint location.The crack width of the I-shaped steel joint is slightly larger than that of the ring-shaped joint,but the crack width is far less than the limit of specification and meets the requirements of specification.(3)The existence of the transverse joint has a certain influence on the bearing capacity of the middle part of the outer side wall of the large body of the gallery,and the impact on the bearing capacity at other locations is negligible.(4)The presence of the transverse joints does not have a large effect on the deformation of the side walls of the corridor and the top and bottom plates.(5)Compared with the I-shaped steel joint,the ring-shaped joint is uniform and flexible,which is more conducive to structural stress.The analysis of the influence of the stiffness degradation of the transverse joint epoxy resin on the mechanical properties of the transverse joint shows that:(1)Theoretically,as the rigidity of the epoxy resin is degraded,stress cross-distribution occurs in the joint cross section.The stress of the concrete around the joint steel plate and the epoxy resin glue is increased,but the transverse joint still meets the requirements of specification,and has a large safety reserve.The bending resistance of the joint is mainly provided by the steel plate.As long as the steel plate has a certain effective area,the safety of the joint can be ensured.(2)As the rigidity of the epoxy resin is degraded,the overall bending stiffness of the transverse joint section is gradually reduced,resulting in an increase in the transverse displacement of the joint,but the impact is small and meets the design requirements.The full-scale model mechanics and waterproof test results show that:(1)Both types of transverse joints meet the design requirements of the limit state of normal use and the bearing capacity,and both have good waterproof propeties.(2)The ring-shaped joint has uniform lateral bending rigidity and good crack resistance,which is more favorable for structural stress.(3)The overall mechanical properties of the gallery are excellent and meet the design requirements.The research in this paper shows that: this “epoxy rubber bonding and steel plate welding” connection form has good mechanical properties and waterproof effect,it can be used as a transverse connection structure of large-section prefabricated pipe gallery.