基于非常规态近场动力学对混凝土动态拉伸断裂的数值模拟研究

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中图分类号：0383 国标学科代码：1303520 文献标志码：A

Abstract：Toacuratelypredictthedynamic tensilefractureinconcretematerialssubjectedtoimpactandblastloadings，this studyfirst establishes a modified Monaghan artificial bulk viscosity computation method within the framework of a nonordinarystate-basedperidyamics（NOSB-PD）theorytoeliminateumericaloscilations.Subsequently，thecorrectedstrainratecomputatiometod，peiouslyeveloped，istegatedintoteong-Fangoeteaterialodel，ichsd earlier by the research group to calculate acurately the strain-rate efect during sudden changes.Basedonthe two methods above，numericalsimulationsofelastic wavepropagationinaone-dimesionalrodareconducted，andtheresultsdemostrate thatheadditional inclusionofthe modified Monaghanartificialbulkviscosityforce vectorstate intotheoriginal force vector statecan effectively suppress the non-physical numerical oscilltionscaused bythe deformation gradient appoximation.The superiorityof themodifiedMonaghanartificialbulkviscosityisvalidated through comparativeanalysis withtheoriginal Monaghanartificialbulkviscosity.Furthermore，theinfluenceofthemodifiedMonaganartificialbulkviscosityparametersis investigated，andrecommended valuesfor theseparametersare providedFinally，theaforementioned model is usedto numericallysimulate the spal test inconcretespecimens，where theeffects ofincluding or excluding the modified Monaghan artificial bulk viscosityand different strain-ratecomputation methodsonthe predictionresultsofdynamic tensilefractureare compared and analyzed.The numerical simulationresults demonstrate that accurately predicting the dynamic tensile fracture in concretematerialsrequiressimultaneousconsiderationofthemodifiedMonaghanartificialbulkviscosityandcorectedstrainratecomputation.Theestablishednon-ordinarystate-basedperidynamicsmodelthataccountsforboththemodifiedMonaghan artificial bulk viscosityand corected strain-rate computation demonstrates strong capabilities in predicting crack locations and quantities based onbothqualitativeandquantitativeanalysis metrics.This work providesnew insights intothenumerical simulation of dynamic tensile fracture in concrete materials under impact and blast loadings.

Keywords：dyamic tensile fracture; modifiedMonaghanartificial bulk viscosity;corrcted strain-rate; non-ordinarystatebased peridynamics

混凝土材料广泛应用于军民用防护工程中，在服役周期内可能会受到蓄意或偶然的爆炸冲击作用。（剩余20458字）