scholarly journals A Stochastic Damage Model for Bond Stress-Slip Relationship of Rebar-Concrete Interface under Monotonic Loading

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3151 ◽  
Author(s):  
Xiaoyong Lv ◽  
Zhiwu Yu ◽  
Zhi Shan ◽  
Ju Yuan
Keyword(s):  
Damage Model ◽  
Monotonic Loading ◽  
Bond Stress ◽  
Experimental Results ◽  
Stochastic Behavior ◽  
Spring Element ◽  
Proposed Model ◽  
Relationship Of ◽  
Stochastic Damage ◽  
Concrete Interface

The stochastic bond stress-slip behavior is an essential topic for the rebar-concrete interface. However, few theoretical models incorporating stochastic behavior in current literature can be traced. In this paper, a stochastic damage model based on micro-mechanical approach for bond stress-slip relationship of the interface under monotonic loading was proposed. In order to describe the mechanical behaviors of the rebar-concrete interface, a microscopic damage model was proposed. By introducing a micro-element consists of parallel spring element, friction element and a switch element, the model is formulated. In order to reflect the randomness of the bond stress-slip behavior contributed by the micro-fracture in the interface, a series of paralleled micro-elements are adopted with the failure threshold of individual spring element is set as a random variable. The expression of both mean and variance for the bond stress-slip relationship was derived based on statistical damage mechanics. Furthermore, by utilizing a search heuristic global optimization algorithm (i.e., a genetic algorithm), parameters of the proposed model are able to be identified from experimental results, which a lognormal distribution has adopted. The prediction was verified against experimental results, and it reveals that the proposed model is capable of capturing the random nature of the micro-structure and characterizing the stochastic behavior.

Stochastic damage model for bond stress-slip relationship of reinforcing bar embedded in concrete

2019 ◽  
Vol 194 ◽  
pp. 11-25 ◽  
Author(s):  
Le Huang ◽  
Hailong Ye ◽  
Shaohua Chu ◽  
Lihua Xu ◽  
Yin Chi
Keyword(s):  
Damage Model ◽  
Bond Stress ◽  
Reinforcing Bar ◽  
Relationship Of ◽  
Stochastic Damage

STOCHASTIC VISCOUS-DAMAGE CONSTITUTIVE MODEL FOR CONCRETE

2013 ◽  
Vol 07 (03) ◽  
pp. 1350027
Author(s):  
JIE LI ◽  
QIAOPING HUANG
Keyword(s):  
Damage Model ◽  
Damage Mechanism ◽  
Failure Behavior ◽  
Strain Rates ◽  
Rate Dependency ◽  
Rate Dependent ◽  
Proposed Model ◽  
Model Predictions ◽  
Damage Constitutive Model ◽  
Stochastic Damage

A new rate-dependent stochastic damage model for the dynamic modeling of concrete is presented in the paper. This model is formulated on the basis of the stochastic damage model, from which, the static stochastic evolution of damage is strictly derived. Then, rate dependency of concrete is included by means of viscous-damage mechanism. The model predictions are tested against experimental results on concrete specimens that cover different strain rates. The results demonstrate the proposed model may predict dynamic failure behavior of concrete quite well.

A Simple Analytical Approach for Creep Analysis of EB-FRP Systems

2018 ◽  
Vol 774 ◽  
pp. 42-47 ◽  
Author(s):  
Hugo Biscaia ◽  
Carlos Chastre
Keyword(s):  
Analytical Approach ◽  
Bond Stress ◽  
Experimental Results ◽  
Elastic Regime ◽  
Analytical Results ◽  
Creep Analysis ◽  
Proposed Model ◽  
Initial Load

Based on a few experimental results available in the literature, this work presents a simple analytical approach that allows the study of the long-term behaviour of CFRP-to-concrete interfaces under an initial sustaining load. Only the elastic regime is studied, which means that the interfacial maximum bond stress and maximum slip are never exceeded. Therefore, the maximum initial load to be sustained by the joints is limited by its corresponding elastic value. The analytical results provided by the proposed model are compared with some experimental results found in the literature. The results showed strain redistribution throughout the bonded length over the time.

Fatigue Life Prediction under Variable Loading Based a Non-Linear Energy Model

2016 ◽  
Vol 22 ◽  
pp. 14-21
Author(s):  
Abdelkader Djebli ◽  
Mostefa Bendouba ◽  
Aid Abdelkarim
Keyword(s):  
Fatigue Life ◽  
Aluminium Alloy ◽  
Fatigue Damage ◽  
Damage Model ◽  
Experimental Results ◽  
Random Loading ◽  
Random Load ◽  
Complex Load ◽  
Proposed Model ◽  
Fatigue Damage Accumulation

A method of fatigue damage accumulation based upon application of energy parameters of the fatigue process is proposed in the paper. Using this model is simple, it has no parameter to be determined, it requires only the knowledge of the curve W–N (W: strain energy density N: number of cycles at failure) determined from the experimental Wöhler curve. To examine the performance of nonlinear models proposed in the estimation of fatigue damage and fatigue life of components under random loading, a batch of specimens made of 6082 T6 aluminium alloy has been studied and some of the results are reported in the present paper. The paper describes an algorithm and suggests a fatigue cumulative damage model, especially when random loading is considered. This work contains the results of uni-axial random load fatigue tests with different mean and amplitude values performed on 6082 T6 aluminium alloy specimens. The proposed model has been formulated to take into account the damage evolution at different load levels and it allows the effect of the loading sequence to be included by means of a recurrence formula derived for multilevel loading, considering complex load sequences. It is concluded that a ‘damaged stress interaction damage rule’ proposed here allows a better fatigue damage prediction than the widely used Palmgren–Miner rule, and a formula derived in random fatigue could be used to predict the fatigue damage and fatigue lifetime very easily. The results obtained by the model are compared with the experimental results and those calculated by the most fatigue damage model used in fatigue (Miner’s model). The comparison shows that the proposed model, presents a good estimation of the experimental results. Moreover, the error is minimized in comparison to the Miner’s model.

Study on the Simulation of Damage Constitutive Relationship for High Strength and High Performance Concrete

2011 ◽  
Vol 250-253 ◽  
pp. 636-639
Author(s):  
Shan Suo Zheng ◽  
Yi Hu ◽  
Bin Liu ◽  
Ming Xie ◽  
Qing Lin Tao
Keyword(s):  
Constitutive Equation ◽  
High Performance ◽  
High Performance Concrete ◽  
Mechanical Test ◽  
Damage Model ◽  
High Strength ◽  
Constitutive Relationship ◽  
Two Parameters ◽  
Relationship Of ◽  
Stochastic Damage

The damage evolution laws of high strength and high performance concrete (HSHPC) are obtained by a large number of experiments on mechanical properties. Based on stochastic damage model, a new damage variable with two parameters is proposed to describe the damage constitutive relationship of HSHPC and the damage constitutive equation is established by boundary conditions. Compared mechanical test result of HSHPC with theoretical calculation, it is shown that the damage constitutive equation can reflect the damage characteristics of HSHPC reasonably. The research identifies a certain theoretical basis for further studying on dynamic and stochastic damage constitutive relationship of HSHPC.

scholarly journals Uniaxial Bond Stress-Slip Relationship of Reinforcing Bars in Concrete

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Sungnam Hong ◽  
Sun-Kyu Park
Keyword(s):  
Reinforced Concrete ◽  
Bond Stress ◽  
Analytical Models ◽  
Cross Sectional ◽  
Concrete Members ◽  
Axial Tension ◽  
Analytical Results ◽  
Proposed Model ◽  
Relationship Of ◽  
Tension Loading

This paper documents a study carried out on the estimation of the bond stress-slip relationship for reinforced concrete members under axial tension loading. An analytical model is proposed that utilizes the conventional bond stress-slip theories as well as the characteristics of deformed bar and concrete cross-sectional area. An equation for the estimation of the bond stress is formulated as the function of nondimensional factors (e.g., bond stress, slip, etc.). The validity, accuracy, and efficiency of the proposed model are established by comparing the analytical results with the experimental data and the JSCE design codes, as well as the analytical models given by Ikki et al. and Shima. The analytical results presented in this paper indicate that the proposed model can effectively estimate the bond stress-slip relationship of reinforced concrete members under axial tension loading.

Mathematical Model for Shear Stress-Strain Relationship of Soil-Concrete Interface during Shear Fracture Process

2007 ◽  
Vol 348-349 ◽  
pp. 881-884 ◽  
Author(s):  
Wei Wang ◽  
Ting Hao Lu ◽  
Bin Xiang Sun
Keyword(s):  
Shear Stress ◽  
Fracture Process ◽  
Shear Fracture ◽  
Hyperbolic Model ◽  
Stress Strain ◽  
Numerical Studies ◽  
Proposed Model ◽  
Strain Relationship ◽  
Relationship Of ◽  
Concrete Interface

Description of shear stress-strain relationship for soil-concrete interface during shear fracture process plays an important role in experimental and numerical studies of soil-structure interaction. In this paper, deficiency of traditional hyperbolic model for the shear stress-strain relationship is analyzed, firstly. Then, a new model with 3 parameters for it is established, which can overcome the deficiency of hyperbolic model. Finally, good agreements have been found between the proposed model and laboratory tests.

scholarly journals Personalized Recommendations Based on Sentimental Interest Community Detection

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Jianxing Zheng ◽  
Yanjie Wang
Keyword(s):  
Recommender Systems ◽  
Community Detection ◽  
Experimental Results ◽  
User Profiles ◽  
Community Based ◽  
Proposed Model ◽  
Communities Of Interest ◽  
Relationship Of ◽  
Resonance Group ◽  
Accuracy Performance

Communities have become a popular platform of mining interests for recommender systems. The semantics of topics reflect users’ implicit interests. Sentiments on topics imply users’ sentimental tendency. People with common sentiments can form resonant communities of interest. In this paper, a resonant sentimental interest community-based recommendation model is proposed to improve the accuracy performance of recommender systems. First, we learn the weighted semantics vector and sentiment vector to model semantic and sentimental user profiles. Then, by combining semantic and sentimental factors, resonance relationship is computed to evaluate the resonance relationship of users. Finally, based on resonance relationships, resonant community is detected to discover a resonance group to make personalized recommendations. Experimental results show that the proposed model is more effective in finding semantics-related sentimental interests than traditional methods.

Connected-Tube MPP Model for Unsupervised 3D Fiber Detection

2020 ◽  
Vol 2020 (14) ◽  
pp. 305-1-305-6
Author(s):  
Tianyu Li ◽  
Camilo G. Aguilar ◽  
Ronald F. Agyei ◽  
Imad A. Hanhan ◽  
Michael D. Sangid ◽  
...  
Keyword(s):  
Composite Material ◽  
Point Process ◽  
Marked Point ◽  
Experimental Results ◽  
Marked Point Process ◽  
Fiber Reinforced Composite ◽  
Reinforced Composite ◽  
Proposed Model ◽  
Cylinder Model ◽  
Reinforced Composite Material

In this paper, we extend our previous 2D connected-tube marked point process (MPP) model to a 3D connected-tube MPP model for fiber detection. In the 3D case, a tube is represented by a cylinder model with two spherical areas at its ends. The spherical area is used to define connection priors that encourage connection of tubes that belong to the same fiber. Since each long fiber can be fitted by a series of connected short tubes, the proposed model is capable of detecting curved long tubes. We present experimental results on fiber-reinforced composite material images to show the performance of our method.

Sign in / Sign up

Export Citation Format

Share Document