锚杆是岩土工程中重要的支护构件,本文基于CZM(Cohesive Zone Model)模型分析全长粘结式锚杆的脱粘破坏特性。结果表明:对于岩石里固化后的水泥灌浆锚杆脱粘破坏主要经过3个阶段:弹性阶段、塑性破坏阶段、完全破坏阶段。锚固长度在一定...锚杆是岩土工程中重要的支护构件,本文基于CZM(Cohesive Zone Model)模型分析全长粘结式锚杆的脱粘破坏特性。结果表明:对于岩石里固化后的水泥灌浆锚杆脱粘破坏主要经过3个阶段:弹性阶段、塑性破坏阶段、完全破坏阶段。锚固长度在一定范围内变化时,增加锚固长度,并不能增大破坏时的位移。展开更多
凝冻天气水闸容易覆冰冻结,影响水闸功能的正常运行,如强行提闸会危害水闸结构安全。为分析水闸积冰提升运行的受力特征,采用了ANSYS有限元分析软件建立输水闸门的覆冰模型,通过CZM(cohesive zone model)模型表达冰在水闸表面的附着力,...凝冻天气水闸容易覆冰冻结,影响水闸功能的正常运行,如强行提闸会危害水闸结构安全。为分析水闸积冰提升运行的受力特征,采用了ANSYS有限元分析软件建立输水闸门的覆冰模型,通过CZM(cohesive zone model)模型表达冰在水闸表面的附着力,实现了提闸脱冰的数值模拟。仿真分析表明,水闸积冰会导致门槽底部产生应力集中,虽然不会直接造成结构破坏,但是随着凝冻天气持续,长期带冰提升容易使结构产生疲劳破坏,威胁水闸安全可靠运行。展开更多
The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al–Li alloy patch-reinforced structure.This paper proposes a method...The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al–Li alloy patch-reinforced structure.This paper proposes a method to determine the key parameters of the adhesive layer of adhesively bonded joints in the Al–Li alloy patch-reinforced structure.A zero-thickness cohesive zone model(CZM)was selected to simulate the adhesive layer’s fracture process,and an orthogonal simulation was designed to compare against the test results.A three-dimensional progressive damage model of an Al–Li alloy patch-reinforced structure with single-lap adhesively bonded joints was developed.The simulation’s results closely agree with the test results,demonstrating that this method of determining the key parameters is likely accurate.The results also verify the correctness of the cohesive strength and fracture energy,the two key parameters of the cohesive zone model.The model can accurately predict the strength and fracture process of adhesively bonded joints,and can be used in research to suppress crack propagation in Al–Li alloy patch-reinforced structures.展开更多
纤维增强材料(简称FRP)已被广泛应用于钢筋混凝土结构的修复和补强。FRP与混凝土的粘结强度是一个重要的设计参数,一般通过单剪试验测得。该文基于内聚力模型(Cohesive Zone Model)进行了单剪试验的有限元模拟,采用三线性应力-张开位移...纤维增强材料(简称FRP)已被广泛应用于钢筋混凝土结构的修复和补强。FRP与混凝土的粘结强度是一个重要的设计参数,一般通过单剪试验测得。该文基于内聚力模型(Cohesive Zone Model)进行了单剪试验的有限元模拟,采用三线性应力-张开位移模型定义内聚单元本构关系,并对一些典型试验的荷载位移曲线进行参数拟合以确定相关参数,其值与文献吻合。进行了参数分析,得到了内聚参数对计算结果的影响规律,并给出了合理选取内聚参数的建议。展开更多
文摘凝冻天气水闸容易覆冰冻结,影响水闸功能的正常运行,如强行提闸会危害水闸结构安全。为分析水闸积冰提升运行的受力特征,采用了ANSYS有限元分析软件建立输水闸门的覆冰模型,通过CZM(cohesive zone model)模型表达冰在水闸表面的附着力,实现了提闸脱冰的数值模拟。仿真分析表明,水闸积冰会导致门槽底部产生应力集中,虽然不会直接造成结构破坏,但是随着凝冻天气持续,长期带冰提升容易使结构产生疲劳破坏,威胁水闸安全可靠运行。
基金Project(51575535)supported by the National Natural Science Foundation of ChinaProject(2015CX002)supported by the Innovation-driven Plan in Central South University,China+2 种基金Project(zzyjkt2013-09B)supported by the Fund of the State Key Laboratory of High Performance Manufacturing,ChinaProject(2017zzts638)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2016RS2015)supported by the Scientific and Technological Leading Talent Projects of Hunan Province,China
文摘The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al–Li alloy patch-reinforced structure.This paper proposes a method to determine the key parameters of the adhesive layer of adhesively bonded joints in the Al–Li alloy patch-reinforced structure.A zero-thickness cohesive zone model(CZM)was selected to simulate the adhesive layer’s fracture process,and an orthogonal simulation was designed to compare against the test results.A three-dimensional progressive damage model of an Al–Li alloy patch-reinforced structure with single-lap adhesively bonded joints was developed.The simulation’s results closely agree with the test results,demonstrating that this method of determining the key parameters is likely accurate.The results also verify the correctness of the cohesive strength and fracture energy,the two key parameters of the cohesive zone model.The model can accurately predict the strength and fracture process of adhesively bonded joints,and can be used in research to suppress crack propagation in Al–Li alloy patch-reinforced structures.
文摘纤维增强材料(简称FRP)已被广泛应用于钢筋混凝土结构的修复和补强。FRP与混凝土的粘结强度是一个重要的设计参数,一般通过单剪试验测得。该文基于内聚力模型(Cohesive Zone Model)进行了单剪试验的有限元模拟,采用三线性应力-张开位移模型定义内聚单元本构关系,并对一些典型试验的荷载位移曲线进行参数拟合以确定相关参数,其值与文献吻合。进行了参数分析,得到了内聚参数对计算结果的影响规律,并给出了合理选取内聚参数的建议。
