Numerical Simulation on Damage and Failure of Recycled Aggregate Concrete with a Lattice Model

A random aggregate model of recycled aggregate concrete is developed in this paper on the base of a mixture ratio. Combining a lattice model with random aggregate of recycled aggregate concrete, lattice elements in the lattice model of recycled aggregate concrete can be classified into five types: (1) nature aggregate, (2) old hardened mortar, (3) new hardened mortar, (4) old interface transition zone (ITZ), and (5) new ITZ. The fundamental mechanical parameters of the lattice elements are chosen from the authors’ test as well as other references. A FORTRAN program of the lattice model is then written with basic theories of finite element method (FEM) for simulating the meso-structural damage of recycled aggregate concrete under uniaxial compression.

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Application of Base Force Element Method to Mesomechanics Analysis for Recycled Aggregate Concrete

Mathematical Problems in Engineering ◽

10.1155/2013/292801 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

Yijiang Peng ◽

Yinghua Liu ◽

Jiwei Pu ◽

Lijuan Zhang

Keyword(s):

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Triangular Element ◽

Aggregate Model ◽

Energy Principle ◽

Aggregate Concrete ◽

Tension Tests ◽

Random Aggregate ◽

Force Element ◽

Element Method

The base force element method (BFEM) on potential energy principle is used to analyze recycled aggregate concrete (RAC) on mesolevel. The model of BFEM with triangular element is derived. The recycled aggregate concrete is taken as five-phase composites consisting of natural coarse aggregate, new mortar, new interfacial transition zone (ITZ), old mortar, and old ITZ on meso-level. The random aggregate model is used to simulate the mesostructure of recycled aggregate concrete. The mechanics properties of uniaxial compression and tension tests for RAC are simulated using the BFEM, respectively. The simulation results agree with the test results. This research method is a new way for investigating fracture mechanism and numerical simulation of mechanics properties for recycled aggregate concrete.

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Fire Damage and Residual Strengths of Recycled Aggregate Concrete

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.348-349.937 ◽

2007 ◽

Vol 348-349 ◽

pp. 937-940 ◽

Cited By ~ 25

Author(s):

Jian Zhuang Xiao ◽

Chuan Zeng Zhang

Keyword(s):

Thermal Cycle ◽

Elevated Temperatures ◽

Recycled Concrete ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Fire Damage ◽

Aggregate Concrete ◽

Failure Patterns ◽

Damage And Failure ◽

Coarse Aggregates

In this paper, recycled aggregate concrete subjected to severe fire or high temperature loading condition is investigated. Special attention of the study is devoted to analyze the fire-induced damage and the residual strengths of recycled aggregate concrete. For this purpose, 160 cube specimens are heated under a single thermal cycle of 20oC (ambient temperature), 200oC, 300oC, 400oC, 500oC, 600o, 700oC and 800oC, respectively. Different replacement percentages of the recycled coarse aggregates (RCA) with 0, 30%, 50%, 70% and 100% are considered. Damage and failure patterns of the recycled aggregate concrete specimens are analyzed systematically based on experimental observations. The residual compressive strengths of the recycled aggregate concrete (RAC) at elevated temperatures are studied and evaluated in details. Some differences between the recycled aggregate concretes with different replacement percentages of the recycled coarse aggregates are observed. On the basis of the experimentally measured residual compressive strengths of the recycled concrete, relationships between the residual compressive strengths of the recycled aggregate concrete and the elevated temperature are derived. The results presented in this paper have direct applications in the design and structural analysis of reinforced concrete structures consisting of recycled aggregate concrete.

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Mesoscopic numerical analysis of dynamic tensile fracture of recycled concrete

Engineering Computations ◽

10.1108/ec-05-2019-0214 ◽

2020 ◽

Vol 37 (6) ◽

pp. 1899-1922 ◽

Cited By ~ 1

Author(s):

Liping Ying ◽

Yijiang Peng ◽

Mahmoud M.A. Kamel

Keyword(s):

Recycled Concrete ◽

Recycled Aggregate Concrete ◽

Failure Pattern ◽

Recycled Aggregate ◽

Tensile Fracture ◽

Aggregate Model ◽

Element Mesh ◽

Content Type ◽

Random Aggregate ◽

Force Element

Purpose Based on the random aggregate model of recycled aggregate concrete (RAC), this paper aims to focus on the effect of loading rate on the failure pattern and the macroscopic mechanical properties. Design/methodology/approach RAC is regarded as a five-phase inhomogeneous composite material at the mesoscopic level. The number and position of the aggregates are modeled by the Walraven formula and Monte–Carlo stochastic method, respectively. The RAC specimen is divided by the finite-element mesh to establish the dynamic base force element model. In this model, the element mechanical parameters of each material phase satisfy Weibull distribution. To simulate and analyze the dynamic mechanical behavior of RAC under axial tension, flexural tension and shear tension, the dynamic tensile modes of the double-notched specimens, the simply supported beam and the L specimens are modeled, respectively. In addition, the different concrete samples are numerically investigated under different loading rates. Findings The failure strength and failure pattern of RAC have strong rate-dependent characteristics because of the inhomogeneity and the inertial effect of the material. Originality/value The dynamic base force element method has been successfully applied to the study of recycled concrete.

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