Poly-Linear Approximation Analysis of Tension Softening Diagram for Concrete

Abstract

Thc tension softeni19 diagram provides valuab 且 e inforlnations to discuss the ・ fra (； tUre behavioT of concrete ． ln this paper ， the numcrical analysis method to calculate the poly −・ 1ilear tens ． ion sefteing Cliagram is investigated ． Thc prediction method for the Ioad − disp 且 acement relationship ミ of concrcte ． with cracks is developed by using the fictitious crack modeL conbept with the K − supe 【 position inethod and the constitutive law by the poly − linear tension sofiening dlagram ． In this m6thod ， 皿 onlinear crack equations are solved by the iteration plogram of evaluating the softening inclinations ． Poly ． 一 ！ inear appToximation mcthod for galculatiI1 琴 the sof し ening diagram from the actual load − displqcerpent culvc is proposed based on the ． crack equation anatysis method ． 1［ he softening diagrams of concTetes 蛸 tb various aggregates and matrix strengths are measured and their characte τistics are ' discusse ' d． Kcy，，ηnlS ： 脚 ∫ε 0 π 3 (-舜επ' π g 伽 8厂am ， poly − ' ∫ ηeσ7 卿 ro曜脚 ∫ 10 馬 CノαC舵 卯 α∫ 1 ρπ，

Back Analysis of Tension-Softening Relationship of Concrete

“…Therefore, there is no iteration required for each incremental step. In contrast to the propose method, the method proposed by Kitsutaka et al 15 requires iterations in each step.…”

The Effect of Volume Fraction of Steel Fiber on the Tensile Softening Behavior in Ultra High Performance Concrete

“…The inverse analysis method suggested by Uchida et al [5] has also been applied in this study for the determination of the tension softening curves of ultra high performance concrete. This method exploits the load-deflection curves obtained from flexural tensile test to perform inverse analysis using FEM model and the poly-linear approximation method proposed by Kitsutaka et al [6,7] was applied to derive the tensile stress-crack mouth opening displacement (CMOD) relationship. The poly-linear approximation method is an established technique of which accuracy has been sufficiently verified for ordinary concrete, its accuracy regard to ultra high performance concrete similar to the material of concern in this study has also been verified by several researchers.…”

Numerical Modelling of UHPFRC: from the Material to the Structural Element

“…This method uses the load (P)-displacement () (deflection) curves obtained from the 3PBT to perform an inverse analysis using a finite element model (FEM) and a poly-linear approximation method. The poly-linear approximation method used, first developed by (Kitsutaka 1993), consists in the determination step by step of a softening stress ()-crack opening (w) concrete response using the fictitious crack model (Hillerborg et al 1976) to obtain the numerical P- curve from the FE application and comparing to the experimental 3PBT curves in an inverse analysis. As a result, the so called "primitive cohesive tensile stress-crack width softening curve" is obtained for UHPFRC.…”