Accurate simulation of the cracking process caused by rust expansion of reinforced concrete(RC)structures plays an intuitive role in revealing the corrosion-induced failure mechanism.Considering the quasi-brittle frac...Accurate simulation of the cracking process caused by rust expansion of reinforced concrete(RC)structures plays an intuitive role in revealing the corrosion-induced failure mechanism.Considering the quasi-brittle fracture of concrete,the fracture phase field driven by the compressive-shear term is constructed and added to the traditional brittle fracture phase field model.The rationality of the proposed model is verified by a mixed fracture example under a shear displacement load.Then,the extended fracture phase model is applied to simulate the corrosion-induced cracking process of RC.The cracking patterns caused by non-uniform corrosion expansion are discussed for RC specimens with homogeneous macroscopically or heterogeneous with different polygonal aggregate distributions at the mesoscopic scale.Then,the effects of the protective layer on the crack propagation trajectory and cracking resistance are investigated,illustrating that the cracking angle and cracking resistance increase with the increase of the protective layer thickness,consistent with the experimental observation.Finally,the corrosion-induced cracking process of concrete specimens with large and small spacing rebars is simulated,and the interaction of multiple corrosion cracking is easily influenced by the reinforcement spacing,which increases with the decrease of the steel bar interval.These conclusions play an important role in the design of engineering anti-corrosion measures.The fracture phase field model can provide strong support for the life assessment of RC structures.展开更多
为了将新型泡沫混凝土动态弹塑性损伤模型应用到防护结构中,首先开展组合式防护结构预制孔装药爆炸试验;随后利用新泡沫混凝土材料模型对试验进行数值模拟验证,并将新模型的模拟结果与LS-DYNA中Soil and Foam模型的模拟结果进行对比;最...为了将新型泡沫混凝土动态弹塑性损伤模型应用到防护结构中,首先开展组合式防护结构预制孔装药爆炸试验;随后利用新泡沫混凝土材料模型对试验进行数值模拟验证,并将新模型的模拟结果与LS-DYNA中Soil and Foam模型的模拟结果进行对比;最后,基于验证的数值模型,开展以梯度泡沫混凝土作为分配层的组合式防护结构预制孔装药爆炸的数值模拟,探讨梯度泡沫混凝土层界面层数和排列方式对组合式防护结构抗爆性能的影响。结果表明,新泡沫混凝土材料模型的模拟结果与试验结果吻合良好,与Soil and Foam模型相比,新模型在应力波传播和损伤破坏方面预测更好,泡沫混凝土层界面层数和排列方式对作用在主体结构上的应力以及分配层的损伤破坏情况有一定的影响。展开更多
基金the National Natural Science Foundation of China(Qing Zhang,Nos.11932006,U1934206,12172121)the Fundamental Research Funds for the Central Universities(Xin Gu,No.B210201031).
文摘Accurate simulation of the cracking process caused by rust expansion of reinforced concrete(RC)structures plays an intuitive role in revealing the corrosion-induced failure mechanism.Considering the quasi-brittle fracture of concrete,the fracture phase field driven by the compressive-shear term is constructed and added to the traditional brittle fracture phase field model.The rationality of the proposed model is verified by a mixed fracture example under a shear displacement load.Then,the extended fracture phase model is applied to simulate the corrosion-induced cracking process of RC.The cracking patterns caused by non-uniform corrosion expansion are discussed for RC specimens with homogeneous macroscopically or heterogeneous with different polygonal aggregate distributions at the mesoscopic scale.Then,the effects of the protective layer on the crack propagation trajectory and cracking resistance are investigated,illustrating that the cracking angle and cracking resistance increase with the increase of the protective layer thickness,consistent with the experimental observation.Finally,the corrosion-induced cracking process of concrete specimens with large and small spacing rebars is simulated,and the interaction of multiple corrosion cracking is easily influenced by the reinforcement spacing,which increases with the decrease of the steel bar interval.These conclusions play an important role in the design of engineering anti-corrosion measures.The fracture phase field model can provide strong support for the life assessment of RC structures.
文摘为了将新型泡沫混凝土动态弹塑性损伤模型应用到防护结构中,首先开展组合式防护结构预制孔装药爆炸试验;随后利用新泡沫混凝土材料模型对试验进行数值模拟验证,并将新模型的模拟结果与LS-DYNA中Soil and Foam模型的模拟结果进行对比;最后,基于验证的数值模型,开展以梯度泡沫混凝土作为分配层的组合式防护结构预制孔装药爆炸的数值模拟,探讨梯度泡沫混凝土层界面层数和排列方式对组合式防护结构抗爆性能的影响。结果表明,新泡沫混凝土材料模型的模拟结果与试验结果吻合良好,与Soil and Foam模型相比,新模型在应力波传播和损伤破坏方面预测更好,泡沫混凝土层界面层数和排列方式对作用在主体结构上的应力以及分配层的损伤破坏情况有一定的影响。
