Structural Stress Analysis Of Backhoe Dredger’s Backactor And Steel Piles

Backhoe dredger is one of the major constructional machine in dredgingfield,which is widely used in port channel construction、 dam constructionmaintenance、defence construction、dredging in environmental protection、landreclamation and other areas.Because of the long development cycle of new productsand the lag of design tools, companies mainly base on experiences and approaches todesign analog in our country. And large domestic dredging equipments almost alldepend on being imported.So it causes a complete lack of competition in themarket.In addition, because of lacking experience of using backhoe dredger and notknowing its technical performance and operating techniques, in the actualconstruction work ultra-deep conditons happen sometimes coupled with its dailywork environment. Therefore, a lot of mechanical faults were generated. But now thedevelopment of finite element structural analysis and virtual prototyping technology,to a certain extent, provides powerful tools and means to solve these problems.This paper argues that S1type DONGE backhoe dredger、1100backactor andsupport deviece for studying.Focusing on three main issues: backactor’s tress、rightsteel pile bending deformation、repeatedly breaking in the lead department.Throughusing of finite element theory and multi-body dynamic theory, combined withSolidWorks, ANSYS and ADAMS software, we ultimately established finite elementmodels of backactor and the dynamic model of backhoe dredger.Based on thesemodels,we discussed and analyzed problems above to lay the foundation for thereformation of the dredger. Main researches are as follows:(1) According to the Chinese Classification Society CCS "rules for the liftingappliances on ships and offshore installations" and GB/T3811-2008" Design rulesfor cranes ",we analysed backactor in four typical conditions that suffered by the loadcombination.(2) Using ANSYS software to creat the finite element model of backactor, weanalyzed four typical conditions in the stress and stiffness.(3) In accordance with a variety of operating conditions, we established themechanical model of the relevant parts such as a hull to analyze the reasons for the deformation of right steel pile. Based on virtual prototype simulation technology andmulti-body dynamic theory, the use of SolidWorks and ADAMS, we created thedynamic model for simulating working conditions under the three steel piles insertingthe seabed soil.In different conditions,we enhanced the different height of the hullandsimulate the hull in stability.(4) On this basis, in the condition under simulating rear side of steel piles in theseabed soil which is not plugged in real situations, a hull floating in different states,backactor unloading and steel pile falls1m, we analyzed the forces on three groups ofropes in this process to obtaine the trend from the regularity to break and the causesof this trend. Then we widened the hull to simulate the force of the rope and toanalyze the effects of widening the hull for the stability.(5) We analyzed and studied the condition that backactor turned to the verticallongitudinal hull for unloading, sudden breaking of the rope near the steel piles.Weunderstood the serious consequences of the moment and suggested improvements bythe simulation based on the above analysis.We hoped to provid references of theactual operation、maintenance and reformation.Draw some important conclusions from the above research.Through finiteelement analysis of backactor and dynamic simulation of backhoe dredger, we can laythe foundation for analysis and solvement of faults in futureand the reformation of thebackhoe dreger.