Le fluage du béton en fonction de la température

Maréchal, Justine

doi:10.1007/bf02475098

Cited by 11 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, calculation of the energy stored by thermal stresses necessitates a good model for creep and thermal shrinkage of concrete at high temperature. Many studies have been devoted to this effect; see e.g., [15,16,17,18,20,27,28]. Further relevant information on the calculation of pore pressure and other aspects can be found in [21,22,23,29,24,25,26].…”

mentioning

confidence: 99%

International Workshop on Fire Performance of High-Strength Concrete, NIST, Gaithersburg, MD, February 13-14, 1997

Phan¹

1997

View full text Add to dashboard Cite

Thermal stress analysis with inclusion of fracture mechanics. Analysis of internal stresses in HSC elements, caused either by thermal stresses or pore pressure buildup, with consideration of other factors such as creep and shrinkage, must be made in order to determine the relative importance of thermal stresses and pore pressure on the tendency for spalling. A fracture mechanic approach may be needed. (4) Coupling of pore pressure andfi-acture process. Accurately measuring and predicting pore pressure buildup during a fire situation is not enough. Experimental data showing that pore pressure does not drop to zero when a crack forms led to a new approach in analyzing the initiation of spalling. Thus modeling to predict spalling should include the effect of cracking and interaction between the pore pressure and the crack. Codes and Standards (1) Standard Test Protocols for Engineering Properties of Fire-Exposed HSC. Internationally accepted protocols for fire testing of HSC, which include guidelines for data collection and reporting, need to be developed to ensure compatibility of results from different test programs. (2) Mechanical Properties-Temperature Design Curves for HSC. Existing design curves for estimating mechanical properties of fire-exposed concrete have been developed based on experimental data of NSC. These design curves have been shown to be unconservative when applied to HSC. Thus, mechanical properties-temperature design curves for HSC at high temperature need to be developed and incorporated into building codes to ensure safety in HSC structures in the event of a fire. Such design curves would also be helpful for assessing the residual strength of HSC structures after a fire. (3) Guidelines for Interpretation of HSC Material Tests and Standard Fire Tests. Engineering properties of HSC at elevated temperature are obtained by testing HSC cylinders or prisms. The measured properties are typically related to the temperature measured at the center of the specimens and are dependent on, among other things, heating rate. Whereas the current standard fire tests, such as ASTM E 119 and ASTM E 1529, prescribe procedures for testing structural assemblies by subjecting them to standard ambient temperature-time histories. These standards characterize the temperature history and duration of exposure inside the test chamber, but not necessarily the temperature and the rate of temperature development within the assemblies. Thus the results of material and standard tests are not directly compatible. Guidelines should be developed to relate the results of these tests. (4) Guidelines for Selecting Realistic Design Fire Exposures. Current standard fire exposures, prescribed by ASTM E 119 and E 1529, ISO 834, and JIS A 1304, do not represent likely temperature histories of real fires. As a result, the exposure conditions specified in these standard fire test methods are not necessarily representative of the conditions that may exist in real fire scenarios. With the current tendency of moving towards performance-based ...

show abstract

mentioning

confidence: 99%

International Workshop on Fire Performance of High-Strength Concrete, NIST, Gaithersburg, MD, February 13-14, 1997

Phan¹

1997

View full text Add to dashboard Cite

show abstract

“…The effect of temperature on acceleration of creep (Maréchal, 1969;Bengougam, 2002) is represented in the model with an Arrhenius law:…”

Section: Hardened Cement Pastementioning

confidence: 99%

“…However, it should be recognized that the interpretation of data obtained in test reactor remains problematic in terms of direct application to light water reactors (LWRs) conditions, because: (1) The temperature and irradi-ation exposure can be significantly higher in test reactors. 2 (Baggio et al, 1995;Bary et al, 2008;de Morais et al, 2009), the amplitude of thermal expansions (Vodák et al, 2004), and the kinetics of shrinkage and creep in the cement paste (Maréchal, 1969). Also, the radiation-induced amorphization of ceramics is controlled by a critical temperature above which full amorphization cannot be reached (Zinkle, 2012).…”

Section: Introductionmentioning

confidence: 99%

Meso-scale modeling of irradiated concrete in test reactor

Giorla

Vaitová

Pape

et al. 2015

Nuclear Engineering and Design

View full text Add to dashboard Cite

A numerical model accounting for the effects of neutron irradiation on concrete at the mesoscale is detailed in this paper. Irradiation experiments in test reactor (Elleuch et al., 1972), i.e., in accelerated conditions, are simulated. Concrete is considered as a two-phase material made of elastic inclusions (aggregate) subjected to thermal and irradiation-induced swelling and embedded in a cementitious matrix subjected to shrinkage and thermal expansion. The role of the hardened cement paste in the post-peak regime (brittle-ductile transition with decreasing loading rate), and creep effects are investigated. Radiation-induced volumetric expansion (RIVE) of the aggregate cause the development and propagation of damage around the aggregate which further develops in bridging cracks across the hardened cement paste between the individual aggregate particles. The development of damage is aggravated when shrinkage occurs simultaneously with RIVE during the irradiation experiment. The post-irradiation expansion derived from the simulation is well correlated with the experimental data and, the obtained damage levels are

show abstract

“…The influence of temperature on the fracture energy of concrete has been widely studied [2,3,4]. Very few studies have looked at both moisture and temperature conditions.…”

Section: Introductionmentioning

confidence: 99%

Effects of the Hygrothermal Conditions on the Fracture Energy of the Concrete

Kallel

Carré

Borderie

et al. 2016

KEM

View full text Add to dashboard Cite

The scenario of a severe accident in the containment building of a nuclear plant results in an increase in pressure, temperature and relative humidity that can reach respectively 5 bars, 140 °C and the saturation of water vapour. As well as the regulatory calculations, accurate knowledge of the thermal and mechanical behaviour of materials and more specifically of concrete is required to carry out more precise numerical simulations. Our study aims to investigate the mechanical behaviour of concrete under homogeneous conditions of moisture and temperature. An experimental apparatus was designed in order to assess the evolutions of the fracture energy of concrete. Different temperature levels up to a maximum of 110 °C and at different values of the controlled moisture content were investigated. The equipment was used to perform DCT (Disk-shape Compact Tension) tests at 30, 90 and 110 °C. Five levels of degree of liquid water saturation (Sw) were investigated for each temperature level.

show abstract

Le fluage du béton en fonction de la température

Cited by 11 publications

References 0 publications

International Workshop on Fire Performance of High-Strength Concrete, NIST, Gaithersburg, MD, February 13-14, 1997

International Workshop on Fire Performance of High-Strength Concrete, NIST, Gaithersburg, MD, February 13-14, 1997

Meso-scale modeling of irradiated concrete in test reactor

Effects of the Hygrothermal Conditions on the Fracture Energy of the Concrete

Contact Info

Product

Resources

About