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1

Comparative assessment of commonly used concrete damage plasticity material parameters

Al-Rifaie Hasan, Mohammed Darbaz

Engineering Transactions

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2022

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Vol. 70, iss. 2

157-181

EN

The non-homogeneous and non-linear mechanical behaviour of concrete complicates the numerical simulations of its corresponding material model. The concrete damaged plasticity (CDP) model is one of the most popular constitutive models for concrete. State-of-the-art CDP material parameters are introduced in Abaqus documentation [1], Jankowiak and Łodygowski [2], and Hafezolghorani et al. [3]. Accordingly, this paper presents a novel comparative study of these commonly-used concrete CDP parameters by assessing the response of plain concrete specimens under quasi-static loading conditions. The research conducts standard laboratory tests: compressive strength test of a concrete cube and three-point flexural test of a plain concrete beam. Sophisticated non-linear computational models are built using Abaqus/CAE and analysed using Abaqus/Explicit solver. The results discuss and compare deformations, damage patterns, reaction forces, compressive strength, tensile stress and modulus of rapture. The thorough study concludes that choosing CDP parameters is case-dependant and should be selected carefully.

2

Ultimate shear response of ultra-high-performance steel fibre-reinforced concrete elements

Tibea C., Bompa Dan V.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

280--295

EN

This paper examines the experimental performance of ultra-high-performance steel fibre-reinforced concrete (UHPSFRC) beams subjected to loads at relatively low shear span-to-depth ratios. The results and observations from six tests provide a detailed insight into the ultimate response including shear strength and failure mode of structural elements incorporating various fibre contents. The test results showed that a higher fibre content results in an increase in ultimate capacity and some enhancement in terms of ductility. Detailed nonlinear numerical validations and sensitivity studies were also undertaken in order to obtain further insights into the response of UHPSFRC beams, with particular focus on the influence of the shear span-to-depth ratio, fibre content and flexural reinforcement ratio. The parametric investigations showed that a reduction in shear span-to-depth ratio results in an increase in the member capacity, whilst a reduction in the flexural reinforcement ratio produces a lower ultimate capacity and a relatively more flexible response. The test results combined with those from numerical simulations enabled the development of a series of design expressions to estimate the shear strength of such members. Validations were performed against the results in this paper, as well as against a collated database from previous experimental studies.

3

Damage analysis of tensioning cable anchorage zone of a bridge superstructure, using CDP ABAQUS material model

Chróścielewski J., Miśkiewicz M., Pyrzowski Ł., Sobczyk B.

Archives of Civil Engineering

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2017

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Vol. 63, nr 3

3--18

EN

Numerical analysis of the tensioning cables anchorage zone of a bridge superstructure is presented in this paper. It aims to identify why severe concrete cracking occurs during the tensioning process in the vicinity of anchor heads. In order to simulate the tensioning, among others, a so-called local numerical model of a section of the bridge superstructure was created in the Abaqus Finite Element Method (FEM) environment. The model contains all the important elements of the analyzed section of the concrete bridge superstructure, namely concrete, reinforcement and the anchoring system. FEM analyses are performed with the inclusion of both material and geometric nonlinearities. Concrete Damage Plasticity (CDP) constitutive relation from Abaqus is used to describe nonlinear concrete behaviour, which enables analysis of concrete damage and crack propagation. These numerical FEM results are then compared with actual crack patterns, which have been spotted and inventoried at the bridge construction site.

PL

W trakcie prac budowlanych związanych z wykonaniem centrycznego sprężenia podłużnego przęseł mostu doszło do silnych zarysowań betonu bloków kotwiących. Pojawiły się znaczne rysy/pęknięcia poziome w strefie zakotwień na wysokości zbrojenia siatkami. W referacie podjęto próbę opisu mechanizmu zniszczenia strefy zakotwień kabli wewnętrznych sprężenia podłużnego jednego z przęseł mostu z wykorzystaniem środowiska metody elementów skończonych (MES) systemu ABAQUS. Wykonano symulację numeryczną niepożądanych zjawisk lokalnych zarysowania w blokach kotwiących kable, które wystąpiło w trakcie procesu sprężania konstrukcji. Miało to na celu ustalenie, od strony mechaniki, przyczyn ich powstania, w kontekście zaprojektowanego i wykonstruowanego układu zbrojenia.

4

Identification of parameters of concrete damage plasticity constitutive model

Jankowiak T., Łodygowski T.

Foundations of Civil and Environmental Engineering

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2005

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No. 6

53-69

EN

The paper presents a method and requirement of the material parameters identification for concrete damage plasticity constitutive model. The laboratory tests, which are necessary to identify constitutive parameters of this model have been presented. Two standard applications have been shown that test the constitutive model of the concrete. The first one is the analysis of the three-point bending single-edge notched conrete beam specimen. The second presents the four-point bending single-edge notched conrete beam specimen under static loadings. In conclusion, the comparison of crack patterns in the numerical and laboratory [2,9] tests has been presented and discussed.

PL

W pracy przedstawiono metodę identyfikacji parametrów materiałowych betonu klasy B50. Przyjęto model matematyczny betonu plastycznego ze zniszczeniem. Określono, jakie testy laboratoryjne są niezbędne do identyfikacji parametrów konstytutywnych tego modelu. Przetestowano użyteczność modelu konstytutywnego w wybranych dwóch zadaniach brzegowych (zginanie trójpunktowe oraz czteropunktowe belki betonowej z nacięciem). Porównano otrzymane mechanizmy zniszczenia ze znanymi wynikami eksperymentów laboratoryjnych [2, 9].