Estimation, based on the maturity function, of the strength of early age concrete cured at elevated temperature

• Autorzy: Wawrzeńczyk J. , Lech M.

Warianty tytułu

PL

Szacowanie wczesnej wytrzymałości betonu dojrzewającego w podwyższonej temperaturze na podstawie funkcji dojrzałości

• Języki publikacji: EN PL

Abstrakty

EN

In mass production of concrete precast units, it is important to optimise technology which would ensure high early age compressive strength of concrete, and also follow the principles of sustainable manufacturing and reduce costs. The paper presents the analysis of results obtained for three series of concretes made from CEM I42.5R cement, at the water-cement ratios of 0.34, 0.38, and 0.42, cured at different temperatures, namely 20, 40 and 60°C, where heating was performed in 16-hour cycle. The analysis aimed at determining functional properties which allow the estimation of concrete compressive strength depending on the temperature history. The Carino-Lew function was adopted to determine the relation between the curing time and temperature and the equivalent curing time t_e. The determined values of cement thermal sensitivity factor ranged 0.023÷0.040, which was related to the w/c ratio and the strength level. An exponential function was developed to express concrete compressive strength dependence on the equivalent curing time t_e. In the authors’ opinion, the function can contribute to the optimisation of the production process of concrete precast units by means of designing the temperature profile, depending on the concrete mix formulation and the assumed level of concrete structural strength.

Słowa kluczowe

EN

precast concrete; thermal curing; maturity function; compressive strength

PL

beton prefabrykowany; utwardzanie termiczne; funkcja dojrzałości; wytrzymałość na ściskanie

• Wydawca: Wydawnictwo Politechniki Świętokrzyskiej
• Czasopismo: Structure and Environment
• Rocznik: 2015
• Tom: Vol. 7, no. 3
• Strony: 123--131
• Opis fizyczny: Bibliogr. 9 poz., rys., tab., wykr., wzory

Twórcy

autor

Wawrzeńczyk J.

• Kielce University of Technology

autor

Lech M.

• Kielce University of Technology

Bibliografia

• [1] Włodarczyk M.: Projektowanie energooszczędnych procesów obróbki cieplnej betonu (Design of energy saving processes for thermal treatment of concrete). Proc of XVI Conf. JADWISIN’98, Serock 1998, pp. 125-132 (in polish).
• [2] Goszczyńska B., Świt G., Trąmpczyński W., Krampikowska A.: Application of the acoustic emission (AE) method to bridge testing and diagnostics comparison of procedures. IEEE Xplore - IEEE Proceedings, 2012, pp. 1-10.
• [3] Plowman J.M.: Maturity and the strength of concrete. Magazine of Concrete Research, Vol. 8, (22) (1956), March, pp. 13-22. [4] ASTM C 1074-04, Standard practice for estimating concrete strength by the maturity method. ASTM Standards Vol. 04.02, ASTM, West Conshohocken, PA.
• [5] Knudsen T.: The dispersion model for hydration of Portland cement: I. General concepts. Cement and Concrete Research, Vol. 14 (1984), pp. 622-630.
• [6] Hansen F.P., Pedersen J.: Maturity computer for controlled curing and hardening of concrete. Nordisk Betong, 1 (1977), pp. 19-34.
• [7] CEN-FIB Model Code 1990.
• [8] Wawrzeńczyk J., Kotwa A.: The possibility of estimation of concrete compressive strength based on the maturity function. CWB, 2013, pp. 145-149.
• [9] Tank R.C., Carino N.J.: Rate constant functions for strength development of concrete. ACI Journal, Vol. 88 (1) (1991), Jan-Feb, pp. 74-83.

Uwagi

EN

The results presented in the publication were obtained during research funded within the framework of the project „RIS Perspectives Świętokrzyskie - IV stage of” No: WND - POKL.08.02.02 - 26 - 001/12 - Human Capital Operational Programme, Priority VIII, Measure 8.2 Transfer of knowledge, Sub-measure 8.2.2 Regional Innovation Strategies.

PL

Wyniki przedstawione w publikacji zostały uzyskane w trakcie badań sfinansowanych w ramach Projektu „Perspektywy RSI Świętokrzyskie – IV etap” nr: WND – POKL.08.02.02-26-001/12 – Program Operacyjny Kapitał Ludzki, Priorytet VIII, Działanie 8.2 Transfer wiedzy, Poddziałanie 8.2.2 Regionalne Strategie Innowacji.