Advanced SearchSearch Tips
Identification of Compliance Function for Early-Age Concrete Based on Measured Strain & Thermal Stress Histories
facebook(new window)  Pirnt(new window) E-mail(new window) Excel Download
 Title & Authors
Identification of Compliance Function for Early-Age Concrete Based on Measured Strain & Thermal Stress Histories
Oh, Byung-Hwan; Shin, Joon-Ho; Choi, Seong-Cheol; Cha, Soo-Won;
  PDF(new window)
Recently, the serviceability and durability of concrete structures under thermal load have received great attention. The thermal stress and clacking behavior of concrete at early ages are one of the important factors that affect such serviceability and durability of concrete structures. Nevertheless, most studies on the behavior of early-age concrete have been confined to the temperature and strain development itself in the laboratory. The desirable efforts to explore the material properties of concrete at early-ages have not been made extensively so far. The purpose of the present study is, therefore, to identify some important material properties that affect the stress behavior of concrete at early-ages. To this end, full-scale concrete base-restrained wall members have been fabricated, and many sensors including thermocouples, strain meters and stress meters were installed inside of the wall members. These sensors were to measure the development of temperatures, strains and stresses at several location in concrete walls during the hardening and curing phase of early-age concrete. By using these measured values of strain and stress, the compliance function at early-age was identified. The basic form of compliance function derived in this study follows the double-power law. However, the results of present study indicate that the values of existing compliance functions are much lower than actual values, especially at very early-ages. It can be seen that the prediction of stresses of early-age concrete based on the proposed compliance function agrees very well with test data. The present study allows more realistic evaluation of varying stresses in early-age concrete under thermal load.
compliance function;early-age concrete;temperature history;strain history;thermal stress;
 Cited by
준-순간 하중에 의한 초기재령 콘크리트의 순간 및 크리프 컴플라이언스 함수,오병환;최성철;박호;

한국콘크리트학회논문집, 2005. vol.17. 1, pp.11-18 crossref(new window)
Springenschmid, R.,(eds), 'Prevention of Thernal Cracking in Concrete at Early Ages,' E&FN Spon 1988, 348pp

Emborg, M., 'Thermal Stresses in ConcreteStructures at Early Ages,' Doctoral Thesis, Lulea University of Technology, Lulea, Sweden, 1989.,285pp

ACI 207.2R-95, 'Effect of Restraint, Volume Change, and Reinforcement on Cracking of Mass Concrete, 'ACI Manual of Practice, 1995, 26pp

Westman, G., 'Thermal Stresses and Concrete Creep,' Doctoral Thesis, Lulea University of Technology, Lulea, Sweden, 1999, 301pp

차수원, '초기재령 콘크리트의 수화과정 모델링과 온도 및 습도응력 해석,' 박사학위논문, 서울대학교, 1999, 202pp

CEB-FIP Model Code 1990, 'CEB Btdlletin d'information No. 213/214' 1993. 437pp

ACI 209R-92, 'Prediction of CreeP, Shrinkage and Temperature Effect in Concrete Structures,' ACI Manual of Concrete Practice., 1997, 47pp

Bazant, Z. R., and Panula, L., 'Practical prediction of time-dependent deformations of concrete,' Materials and Structures, V. 11, No. 65, 1978, pp. 307-328, V. 11, No. 66, 1978, pp. 415-434, V. 12, No. 69, 1979, pp.169~183

Bazant, Z. P., 'Mathematical Modeling of Creep and Shrinkage of Concrete,' John Wiley and Sons, 1988, 459pp

Neville, A. M, Dilger, W. H. and Brooks, J. J., 'Creep of plain and structural concrete' Construction Press, 1983, 351pp

Chapra, S. C., and Canale, R. R., 'Numerical Methods for Engineers,' McGraw-Hi11,1990, 812pp