《Finite Elements in Analysis & Design》刊登“利用不同阻尼机制的塑性损伤模型研究混凝土重力坝的地震开裂”

作者：Omidi Omid,Valliappan Somasundaram,Lotfi Vahid

刊物：《有限元分析和设计》，2013，第63卷，80-97页

关键词：重力坝，阻尼，混凝土坝，非线性方程，模拟方法与建模，塑性

摘要：利用两个不同的阻尼机制，通过三维空间中的一个塑性损伤模型研究混凝土重力坝的地震开裂响应。使用了基于Lee和Fenves提出的二维平面应力情况材料本构关系。该塑性损伤模型是建立在非关联多硬化塑性和各向同性损伤理论的结合基础上得到的可以被用来模拟混凝土开裂过程中发生的不可逆损伤，其适用于循环加载或动态加载。本研究中，将HHT方案作为隐形算子，通过时间积分过程反复解非线性控制方程。进一步比较了由于常阻尼机制和损伤相关阻尼机制引起的重力坝地震裂缝响应。通过一些简单例子的解决并给出了计算结果评估指定模型的有效性。随后分析了有抗震框架结构典型问题的Koyna重力坝。结果表明，在混凝土大坝的抗震分析中采用损伤阻尼机制会导致了大量的损伤，与常数阻尼机制相比也能预测更可靠的裂缝形式。另外还包括坝水之间的相互作用会增强两种阻尼机制计算结果的差异。

Seismic cracking of concrete gravity dams by plastic–damage model using different damping mechanisms.

Authors: Omidi Omid,Valliappan Somasundaram,Lotfi Vahid

Journal: Finite Elements in Analysis & Design. Jan2013, Vol. 63, p80-97. 18p.

Key word: GRAVITY dams,DAMPING,CONCRETE dams, NONLINEAR equations, SIMULATION methods & models,PLASTICITY

Abstract: Utilizing two different damping mechanisms, seismic cracking response of concrete gravity dams is examined by a plastic–damage model implemented in three-dimensional space. The material constitutive law employed herein is based on the one proposed by Lee and Fenves for the 2-D plane stress case. This plastic–damage model basically intended for cyclic or dynamic loading was founded on the combination of non-associated multi-hardening plasticity and isotropic damage theory to simulate the irreversible damages occurring in fracturing process of concrete. In this study, considering the HHT scheme as an implicit operator, the time integration procedure to iteratively solve the governing nonlinear equations is presented. Further, seismic fracture responses of gravity dams due to constant and damage-dependent damping mechanisms are compared. In order to assess the validity of the proposed model, several simple examples are solved and their results are presented first. Subsequently, Koyna gravity dam, which is a benchmark problem for the seismic fracture researches, is analyzed. It is concluded that employing the damage-dependent damping mechanism leads to more extensive damages and also predicts more reliable crack patterns in comparison with the constant damping mechanism in seismic analysis of concrete dams. Furthermore, including dam–water interaction intensifies the existing differences between the results of the two damping mechanisms.

原文链接：https://vpn2.nlc.gov.cn/prx/000/http/web.ebscohost.com/ehost/detail?vid=16&sid=06a1f387-ba17-4034-9b33-79ed8b1229ae%40sessionmgr4&hid=19&bdata=Jmxhbmc9emgtY24mc2l0ZT1laG9zdC1saXZl#db=a9h&AN=83321684