Research On Mold Structure And Key Structure Of Cover Plate Split Pipe Gallery

Urban comprehensive pipe gallery can realize the"unified planning,unified construction and management"of municipal public pipelines,and meet the comprehensive development and utilization of urban road underground space.It has become the development direction of municipal pipeline construction at home and abroad.As a new type of prefabricated pipe gallery,the cover plate type separated pipe gallery is expected to effectively solve the problems of difficult assembly process,insufficient manufacturing accuracy and long construction period in the construction of existing prefabricated separated comprehensive pipe gallery.However,the height dimension of the lower part of the prefabricated cover type split pipe gallery is larger than that of the conventional split pipe gallery,and the corresponding pouring mould has higher requirements in the dimension accuracy,stiffness and strength,and the structure and convenience of the opening and closing mechanism.In this paper,according to the structural characteristics and pouring requirements of precast slab type separated pipe gallery,the mould structure and its key components of precast slab type separated pouring pipe gallery are designed and analyzed.The main research contents and results are as follows:（1）The overall structure and key components design of prefabricated slab type split pouring pipe gallery mold.Through the analysis of the structural characteristics,mold structure function,working condition and technical requirements of prefabricated cover type split pouring pipe gallery,combined with the research means of practical application experience and theoretical analysis of concrete structure engineering,the mold system composition of prefabricated cover type split pouring pipe gallery is determined,and the overall structure design of pipe gallery mold is completed;the side mold system,end mold system and internal mold system of pipe gallery mold are analyzed The key structures of die system,bottom die system,roller mechanism and fastening auxiliary mechanism were studied and designed,and the structural design meeting the functional requirements of pipe gallery die was completed.The feasibility of the design is verified by the static analysis of the cover plate type split pouring pipe gallery mold.（2）Research on the lightweight of the mould structure of prefabricated slab type split pouring pipe gallery.Based on the static simulation analysis of the reinforced rib side template,the rectangular tube is selected as the reinforced rib;the topology optimization method is used to rearrange and optimize the structure of each part of the cover type split pouring pipe gallery mold and the reinforced rib;the mechanical analysis of the side template of the pipe gallery mold before and after the structure optimization is carried out by Hyper Works software,which shows that the pipe gallery mold has inherent advantages after the topology optimization The total weight of the original structure before topology optimization is 5.156t,and the total weight after topology optimization is 4.536t.the weight is reduced by 12.0%,which achieves the purpose of lightweight design.（3）Modal analysis and fatigue life analysis of the mould for prefabricated cover slab type split pouring pipe gallery.Using the finite element analysis method and Hyper Works software,the structural mode and fatigue life of the die were analyzed.The analysis results show that the first six natural frequencies of the pipe gallery die structure are between 40.715Hz and 80.372Hz,far away from the vibration frequency of the vibrator,there will be no resonance damage;the fatigue stress cycle of most parts of the pipe gallery die structure reaches 10¹⁹times,and the fatigue life of the small die area reaches 1.222×10³,which meets the design requirements.The performance of the die under the working state meets the requirements of static and dynamic,and the design has practical engineering guidance.At present,it has been used in the production of pipe gallery products.（4）Structure design of automatic opening and closing mechanism.Through the analysis of the function and design requirements of the automatic mold opening and closing mechanism,a hydraulic driven plane low pair mechanism for automatic mold opening and closing is designed,and the structural parameters of each part of the mechanism are designed.In the mechanism,the dead center position characteristics of mechanism and hydraulic locking are applied to ensure the reliable locking of the mechanism when closing the mold,ensure the normal operation of the mold,and save labor when opening the mold,which can improve the automation level of the production of prefabricated parts.The mechanical properties,modal and motion simulation analysis of the mechanism are carried out,and the results show that the structural design of the opening and closing mechanism meets the design requirements,and the opening and closing mechanism can work in the working state keep a relatively uniform movement speed,meet the design requirements of the opening and closing of the pipe gallery mold,and lay a foundation for the subsequent practical application.