Active and non-active porosity in concrete Part II: Evaluation of existing models

Abstract

A B S T R A C T R I~ S U M !~Mechanical, semi-empirical, and theoretical models suitable for describing concrete mechanical properties (modulus of elasticity, bulk modulus, and ultrasonic pulse velocity) are evaluated. Extensive experimental data is generated from saturated and dry concrete specimens with varying volume of active and non-active pores. Experimental data established that active and non-active pores appear at different aspect ratios furthermore, active pores change shape with moisture content. The experimental data is compared to those obtained from these three model categories. Models are evaluated based on their capability in evaluating the effect of pores during dry and saturated states. One model, capable of representing pores at various aspect ratios, was successful in describing mechanical properties in dry and saturated states. ii !! Les r(sultats d' une ~tude visant h ~valuer la fiabilit( de diff(rents modbles permettant de prMire les propri~t~s mdcaniques (module dlastique, vitesse de propagation d'une onde ultrasonique) sont pr(-sent~s. Trois diffdrents types de modkles ont ~td consid~r~s : des modkles m~caniques, semi-empiriques et th~oriques. De nombreuses donne'es exp~rimentales ont ~t( g~n~r~es dans le cadre de cette ~tude. Le programme experimental visait h ~tudier le comportement d'~prouvettes de b~ton sec et humide p@ar~ ~ difl~rentes teneurs en pores actifs (pores capillaires) et non-actifs (vides d' air). Les r~sultats des essais indiquent que les pores actifs et non-actifs ont diff~rents coefficients de forme et que la gkom~trie des pores actifs varie en fonction de la teneur en eau du b(ton. Les prMictions obtenues avec les

Ionic Liquids in Refinery Desulfurization: Comparison between Biphasic and Supported Ionic Liquid Phase Suspension Processes

“…Finally, we confront these results with the experimental data of 59 obtained on dried and saturated concrete. These experimental results exhibit important discrepancies between dry and wet states of the material, which according to 56 and 58 are caused at least partly by the fact that pores are not spherical but more surely oblate‐shaped. It is indeed asserted in 56 that the pore shape varies from nearly spherical for wet material to oblate for dry material.…”

“…The knowledge of the mechanical parameters as a function of the saturation degree is motivated by experimental results revealing a significant difference between fully saturated and desaturated concrete (e.g. 56). In this case the testing procedure is usually very rapid so that we may expect that the material is loaded under quasi‐undrained conditions, i.e.…”

Review of the study on macro-mechanical characteristics of wet concrete and their analysis methods

“…Yaman (2002) predicted the elastic modulus of saturated concrete using the equivalent composite material method established based on the Mori-Tanaka method and Kuster-Toksoz theory [2]. Mori-Tanaka method is a method to calculate the elastic modulus of non-homogeneous material, which was established by Mori and Tanaka in 1973 based on Eshelby equivalent inclusion principles [21].…”

“…In the past few years, the saturated concrete is always selected as the study object for scholars in the research of concrete mechanical performance in harbor engineering. At present, the macro-mechanical property study of saturated concrete has gotten studied in depth, and many achievements have been made in the macro-mechanical properties test of saturated concrete and meso-mechanical theory [1][2][3][4][5][6]. Based on the experiments, Powers (1946) and Yaman (2002) pointed out that the static strength of saturated concrete decreased and the elastic modulus and Poisson's ratio increased comparing with the dry concrete [1,2,7].…”

“…At present, the macro-mechanical property study of saturated concrete has gotten studied in depth, and many achievements have been made in the macro-mechanical properties test of saturated concrete and meso-mechanical theory [1][2][3][4][5][6]. Based on the experiments, Powers (1946) and Yaman (2002) pointed out that the static strength of saturated concrete decreased and the elastic modulus and Poisson's ratio increased comparing with the dry concrete [1,2,7]. carried out the study on varying rules of compressive performance of saturated concrete and splitting tensile performance under different loading rate through the material mechanics experiment of concrete, and the test results show 5th International Conference on Advanced Design and Manufacturing Engineering (ICADME 2015) that the compressive strength and splitting strength of saturated concrete decreased under quasi-static loading compared with the dry concrete.…”