Numerical Analysis for the Mechanism of Deterioration of Mortar by Chemical Attacks D2 Yuji OIWA

Today’s Topics Background & purpose Last presentation Research results

Background of my research Recently, it seems that… ・ Decrease of natural aggregate resource ・ Increase of waste concrete in the future New disposal system are developing. Aggregate resumption Neutralize waste water Functionality material Waste concrete

Purpose of my research Aggregate resumption Neutralize waste water Functionality material Waste concrete 1.Clarify the mechanism of deterioration of mortar by chemical attacks 2.Simulation of deterioration of mortar numerical analysis My research associate red zone. In concrete teams,

Purpose of my research 10 2 [m] 10 1 [m] 10 0 [m] [m] Structure Member Element (meso-scale) (Member=homogeneous) (Element=homogeneous) Verification Constitutive model [m] Microscopic phenomena e.g. cracking and stress concentration can be simulated. Because of the heterogeneity, environmental effects are easy to be introduced and combined with the mechanical action. Chloride ion Referenced Matsumoto paper

Stress(MPa) width(mm) Last presentation Our RBSM can not simulate all of 3 kind experiment (bending, compression, tension) quantitatively. Only Compression. But other 2 experiment cannot be. Modification of constitutive law is necessary. Constitutive law is re-evaluated. Laod(kg) Displacement(mm) Bending Tension

Last presentation Parametric analysis First, Tensile constitutive law is modified Constitutive law is re-evaluated. Kind of analysis Affection of constitutive law tensionCompressionShearVariation Tension ◎△△△ Compression○○ ◎◎ Flexure ◎△△△ Tension Stress(MPa) width(mm) Bending Laod(kg) Displacement(mm)

Last presentation Other constitutive law is not determined. Because, there are multi-pairing of shear and variation. Parametric analysis Kind of analysis Affection of constitutive law tensionCompressionShearVariation Tension ◎△△△ Compression○○ ◎◎ Flexure ◎△△△ Shear model changed Variation put Almost same ≒ Constitutive law is re-evaluated. Stress(MPa) Displacement(mm) Stress(MPa) Displacement(mm)

Research results Some problems are not solved yet. 1.Variation and shear spring model is not determined. There are multi-pairing of shear and variation. 2.My constitutive law are determined from other researchers. And three experiment data is not same mortar. ・ Experiment is necessary using same mortar in our laboratory.

Research results Current bending test system have some gaps of Displacement. ExperimentAnalysis gap Steel plate

Research results Comparison of analysis data with good experimental data (Miura kun’s data)

Research results Comparison of analysis data with good experimental data (Miura kun’s data)

Environmental control room Research results Grade up universal testing machine in Q laboratory BeforeAfter

Research results Following box are made for setting displacement measurer. Displacement Measurer

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