Study On Predicting Or Controlling Blasting Fragment And Numerical Simulation Of Cofferdam Demolition

Hydropower is publicly known as the clean and renewable energy which has theprospects for development of the scale. The development of the world’s hydropowerduring the most prosperous periods, the construction of numerous hydropowerprojects provides a good platform for scientific research and practice aboutdeveloping blasting technology, while the advanced blasting technology whichespecially is the blasting technology of cofferdam demolition also provides supportand indemnity to the engineering constructions. The core of blasting technology ofcofferdam demolition is that ensure a successful blast, meeting the request of blastingfragment and accumulation state on the premise of ensuring the security of thehydraulic structures in blasting areas. Therefore, it has important significance thatpredicts and researches the blasting fragment and accumulation state of cofferdamdemolition.First of all, this article details the research current situation, the theoreticalanalysis and evaluation of the forecasting models of blasting fragment. It selected theforecasting model which is fit for the blasting fragment of cofferdam demolition. Themodel is fixed by theoretical analysis and model tests, getting the forecasting modelwhich is suitable for underwater blasting fragmentation. Secondly, it introduces somebasic theory about prediction of accumulation state of cofferdam demolition, and thisbasic theory‘s practical application in accumulation state prediction of entrance andexit cofferdam demolition in Xiaowan Hydropower Station. Then it summaries andresearches influence of the blasting parameters as drilling form, charge constitution,spacing pattern parameter, network ignition, line of resistance on controlling theaccumulation state. Last, it uses the software ANSYS/LS-DYNA for numericalsimulation, studying on the measures and methods for improving fragmentation effectof blasting of cofferdam demolition, mainly analyzed from these pacts as specificcharge, initiation position of blasting cartridge, and the blocking materials of blast hole, getting gainful parameters to guide engineering practice.The key point of the research includes: it gets the forecasting model ofunderwater blasting fragmentation by analyzing the differences between blastingunderwater and blasting on land; it researches the influence of blasting parameters oncontrolling the accumulation state; it studies on the measures and methods ofimproving fragmentation effect for blasting of cofferdam demolition by numericalsimulation.