| Large section prefabricated and assembled comprehensive pipeline Gallery usually needs transverse partitioning to meet the requirements of transportation because of its size and weight exceeding the limit.In this paper,a new type of "epoxy glue + steel plate welding" is proposed to replace the traditional transverse prestressing connection,so as to improve the site construction progress,that is,the upper and lower half of the corridor concrete interface is bonded by epoxy resin,and the outer part is welded by embedded steel plate to make it a whole corridor.Based on a prefabricated and assembled comprehensive pipeline Gallery project,the reinforcement calculation of the whole pipeline gallery is carried out according to the cross-section form given by the design institute and the relevant design specifications.Through field 1:4 scale model test and ABAQUS,a non-linear finite element calculation software,respectively,to simulate the adverse geological conditions on site,the anti-uneven settlement ability of this multi-compartment prefabricated pipe gallery with transverse joints was studied from two aspects of segment assembly length and prestress loss.The study of segment assembly length chooses 12 m and 25 m working conditions for comparative analysis.The study of prestress loss chooses five working conditions: 0,10%,20%,30% and 40% for comparative analysis.The purpose of this study is to explore the non-uniform settlement resistance of the gallery with this transverse joint under different conditions,so as to provide a basis for the follow-up study and promotion.The analysis of the influence of segment assembly length on the uneven settlement of gallery shows that:(1)the longer the segment assembly length is,the softer the soil is,the greater the settlement displacement of gallery and the stress of concrete and steel bar;(2)the maximum settlement occurs in the position of large cabin at the end of section on soft soil foundation,the minimum settlement occurs in the position of small cabin at the end of section on hard soil foundation,and the maximum tensile stress of concrete and steel bar develops.Born at the bottom of the middle web;(3)When the geological conditions transit from hard soil to soft soil,the settlement displacement of the pipe gallery increases linearly and smoothly,and the change of concrete stress decreases first and then increases in a parabolic form;(4)The difference of uneven settlement between two segments of assembly length is less than the allowable settlement value recommended in this paper,and both assembly lengths meet the settlement requirements in this area.The analysis of the influence of prestressing loss on the uneven settlement of gallery shows that:(1)the larger the prestressing loss is,the larger the settlement displacement of gallery on soft soil foundation is,the greater the stress of concrete and reinforced steel skeleton is,whereas in hard soil foundation,with the gradual loss of prestressing force,the settlement displacement and stress of Gallery on the gallery decrease;(2)when the prestressing loss increases,the concrete at the soil boundary decreases.The stress changes intensify,the concrete stress at the interface of gallery and soil on the hard side increases,the concrete stress at the end decreases,and the concrete stress at all parts of gallery on the soft side increases continuously;(3)Under this geological condition,when the loss of prestress reaches 40%,the stress of splice section reaches the minimum value of Engineering design,and the difference of settlement and displacement of gallery section exceeds the uneven settlement recommended in this paper.Permissible value,at this time,may have an adverse impact on waterproof materials and other ancillary facilities,and then may affect the safety and durability of the overall structure. |
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