Comprehensive study of concrete creep, shrinkage, and water content evolution under sealed and drying conditions

Abstract

A comprehensive study of the time-dependent behaviour of concrete, enhanced by measuring the evolution of the respective mass water content, is presented. Compressive creep as well as shrinkage are investigated on sealed and unsealed specimens in terms of the concrete age at loading of 2, 7, and 28 days, respectively, at a loading level of 30% of the compressive strength at loading. In addition, on the basis of the collected measurement data, the impact of load application on the moisture content is studied and the Pickett effect is re-examined. The obtained set of material data consists of basic and drying creep strains for different concrete ages at loading, autogenous shrinkage strains as well as combined autogenous and drying shrinkage strains, the evolution of the mass water content, the water desorption isotherm, and the time-dependent evolution of Young's modulus and the compressive strength. It provides a consistent set of material data for a particular concrete grade and will be available for calibrating and validating concrete models. KEYWORDS basic and drying creep, concrete, mass water content, Pickett effect, shrinkage

Bonded Concrete Overlays: A Brief Discussion on Restrained Shrinkage Deformations and Their Prediction Models

“…At that point, however, the local moisture conditions would have to change. This peculiarity has been discussed by Theiner [72], Wyrzykowski [73], and Tamtsia [68] just to mention a few. On one hand Wyrzykowski recorded change in internal humidity, yet creep is known to occur in immersed conditions as well, as was given by Young [74], as it was pointed out by Theiner [72].…”

“…This peculiarity has been discussed by Theiner [72], Wyrzykowski [73], and Tamtsia [68] just to mention a few. On one hand Wyrzykowski recorded change in internal humidity, yet creep is known to occur in immersed conditions as well, as was given by Young [74], as it was pointed out by Theiner [72]. It has to be noticed, that in sealed conditions, due to occurring hydration, pore system is desiccated as well, therefore concrete specimen should be water cured in controlled way, for at least several months in order get rid of any moisture gradients inside the specimen and to obtain perfect imbibition of the specimen.…”

Investigation of Tensile Creep of a Normal Strength Overlay Concrete

“…Immediately after determining the properties of fresh concrete and a further short mixing, the following specimens were cast: Cubes with an edge length of 150 mm for determining the average cube compressive strength, Prisms with dimensions of product-units = single mm for determining the average Young’s modulus, Prisms with dimensions of product-units = single mm for determining the water desorption isotherm, recently published in [ 45 ], Cylinders with 150 mm diameter and 300 mm height for determining the average splitting tensile strength, Cylinders with 150 mm diameter and 450 mm height for determining both the average uniaxial tensile strength and compressive strength, Cylinders with 150 mm diameter and 450 mm height for the compressive creep tests, recently published in [ 45 ], the tensile creep tests, and the companion shrinkage tests. …”

“…The present study is connected to a recent study [ 45 ], in which the compressive creep behavior and the respective evolution of the moisture content have been investigated for the same concrete mixture. These results are available in the database assembled at Northwestern University [ 12 ].…”

Benefits of porosity‐dependent moisture retention modelling for predicting autogenous shrinkage of concrete

“…For D = 0, the moisture retention function for soils [5] is recovered. The parameters in (1) and the other parts of the multiphase model have been thoroughly calibrated in [3] for a specific concrete mixture investigated experimentally in [7,8], for instance. The parameters in (1) and the other parts of the multiphase model have been thoroughly calibrated in [3] for a specific concrete mixture investigated experimentally in [7,8], for instance.…”