The Structural Static Analysis Of Multi-troughs Rectangular Aqueduct

The regional differences in distribution of water resources is great in our China, whichseriously hinders the rapid development of socio-economic, and also further increases the gapbetween the rich and the poor in the eastern and western regions. In order to make China’ssocio-economic balanced development and overall national strength increase significantly,many largely hydraulic engineering are constructed gradually. In these hydraulic projects,aqueduct is widely used as a kind of cross-linked hydraulic structures. With the constantexpansion of the water transfer and diversion projects, the aqueduct discharge is increasingaccordingly. Simple single-trough aqueduct structure has been to difficulty meet the needs ofthe practical project. So the multi-troughs aqueduct structure has been designed to solve theactual problems. For the multi-troughs aqueduct structure, due to the number of the side wallsis increased so that its structure type is complicated. Aqueduct cross-section size is very large,the discharge is great, and the aqueduct structure force is more complex than the single-trough conveyance. After multi-troughs conveyance type is adopted, water load assigned toeach stringer along the body horizontal becomes very complicated. These emerging practicalengineering problems are not to be resolved by the existing mature theories. So it is quitenecessary to study force characteristics on the body of multi-troughs rectangular aqueduct inorder to accurately analyze the transverse and longitudinal mechanical characteristics anddeformation characteristics, summarize the practical computational analysis methods, andprovide a reference for the design of multi-troughs rectangular aqueduct.In this paper, according to structure style and mechanical characteristics of thelarge-scale multi-troughs rectangular aqueduct, the “practical space method” is selected toconduct the structure calculation and analysis of multi-troughs rectangular aqueduct. Whenanalyzed, aqueduct structure is divided into two related-linked plane problem. While aqueducthorizontal structure is calculated, the supporting structure between the beams and stringerschooses the type of elastic support, beams are supported on top of each stringer. According tothe force deformation coordination theory, the reaction force calculation formula of the elasticsupport on the horizontal structure of the twin-aqueduct and triple-aqueduct is deduced, theninternal force and supporting force of the beam will be calculated under the conditions of theelastic support. Firstly calculating supporting force ratio on each the beams, then makestatistics for the anti-force ratio coefficient on each stringer at beams position to get the waterload distribution coefficient on the stringer, the water load distribution will be calculated bythis load distribution coefficient, and the force of each stringer can be analyzed. Bycalculation, water load lateral distribution coefficient, water load distribution on each stringer,stress distribution law on the bottom edge of the beams and stringers, and displacement change trend on each stringer can be gotten. The finite element computing software(MIDAS)is adopted to the overall modeling analysis for a grand three-troughs rectangular aqueductsingle span aqueduct body, and then a comparison is made for the results of finite elementmethod and practical space method, which verifies that “practical space method” is used forgrand multi–troughs rectangular aqueduct structure design, it has accurate structuralcalculations, it is simple, fast and high-precision, and can bring great convenience forengineering design. According to the calculation results of “the practical space method”, thebody of multi-troughs aqueduct has been optimized by adding rods on the top of straight wallsand setting longitudinal prestressed steel bars. Then calculating optimized aqueduct structureby FEM and making a comparison for the result of optimized and unoptimized aqueductstructure, the results show that after the aqueduct is added rods on the top of straight walls andset longitudinal prestressed steel bars, the stress of lower edge on stringers is changed thetensile stress state into the compressive stress state, the vertical displacement of stringersbecomes slightly upward from downward. This suggests that structure stress and deformationare more reasonable after optimizing. In the paper, longitudinal prestressing is just considered,which is no use for transverse force, so we should design three-dimension prestressedstructure in practical projects. In the paper, the body structure stability of optimized aqueducthas been researched, the results show that the body structure stability is greatly improved afteroptimization, and the measures are useful for the stability of aqueduct.In this paper, the “practical space method” has been selected to analyze aqueductstructure by the compaction of some analysis methods. Through the theoretical analysis andfinite element calculations, the accuracy and practicability of the “practical space method”have been verified in aqueduct structural analysis. This method should be used widely in theactual engineering design. The FEM must be used at some local complex parts to ensure thesecurity and economy of the engineering design.