Study on water absorption model of air-entraining concrete under natural conditions

被引：0

作者：

Yang Q. ^{[1
]}

Li K.-F. ^{[1
]}

机构：

[1] Department of Civil Engineering, Tsinghua University, Beijing

来源：

Gongcheng Lixue/Engineering Mechanics | 2022年 / 39卷 / 05期

关键词：

Absorption modelling; Air-entrained concrete; Pore saturation; Railway works; Service life model;

D O I：

10.6052/j.issn.1000-4750.2021.03.0165

中图分类号：

学科分类号：

摘要：

The freeze-thaw damage of air-entraining concrete in natural environment is caused by the intrusion of external water and the saturation process in the capillary pores and air-entraining voids. By discussing the process of air dissolution and diffusion, a revised absorption model is built based on Fagerlund's classic long-time absorption theory. The air-entraining mortar absorption test is performed to validate the improved model. Considering the drying-wetting actions, the absorption model of air-entraining concrete in natural environment is proposed. This model consists of two phases: the water intake in natural environment affected by drying and wetting; the saturation of pore-voids system by external water intake. The water intake under natural drying-wetting cycles is evaluated through the concepts of moisture influential depths and equilibrium drying-wetting time ratio. The pore-void saturation process employs the revised absorption model to predict the change of the saturation degree. Afterwards, the two-stage freeze-thaw service life model is applied to a major railway construction project. On the basis of the local meteorological data and of the predetermined characteristics of structural concrete, the key design parameters are obtained with respect to the frost actions and the expected service lives. Copyright ©2022 Engineering Mechanics. All rights reserved.

引用

页码：159 / 166and176

共 25 条

[1] Shi Xudong, Wang Wenqiang, Tian Jialun, Experimental study on the compressive strength of concrete of different strength grades experiencing ultralow temperature freeze-thaw cycle action, Engineering Mechanics, 37, 2, pp. 211-220, (2020)
[2] Luo Daming, Niu Ditao, Su Li, Research progress on durability of stressed concrete under environmental actions, Engineering Mechanics, 36, 1, pp. 1-14, (2019)
[3] Wei Qiang, Xie Jian, Wu Honghai, Experimental analysis on properties of concrete after freeze-thaw cycles under extra-low temperatures, Engineering mechanics, 30, 1, pp. 125-131, (2013)
[4] Fagerlund G., Mechanical damage and fatigue effects associated with freeze-thaw of materials, Materials & Structures, pp. 117-132, (2002)
[5] Ehlen M A, Bentz D P., Service Life Prediction for Concrete Pavements and Bridge Decks Exposed to Sulfate Attack and Freeze-Thaw Deterioration, Volume I: CONCLIFE User's, (2001)
[6] Moradllo M K, Qiao C, Ghantous R M, Et al., Quantifying the freeze-thaw performance of air-entrained concrete using the time to reach critical saturation modelling approach, Cement and Concrete Composites, 106, (2019)
[7] fib Bulletin 34: Model Code for Service Life Design, (2006)
[8] Zeng Qiang, Poromechanics of freezing behavior of cement-based porous materials saturated with salt solution, (2012)
[9] C1585-20, Standard test method for measurement of rate of absorption of water by hydraulic-cement concrete, (2020)
[10] Eriksson D, Gasch T, Ansell A., A hygro-thermo-mechanical multiphase model for long-term water absorption into air-entrained concrete, Transport in Porous Media, 127, 1, pp. 113-141, (2019)

← 1 2 3 →