Effects of temperature and temperature gradient on concrete performance at elevated temperatures

Le, Quang Minh; Dao, Vinh; Torero, José L.; Maluk, Cristián; Bisby, Luke

doi:10.1177/1369433217746347

Cited by 37 publications

(20 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be inferred from the above review that measurement of structural displacements and strains has been mostly performed outside the heated zone in previous fire tests of concrete. [38]. The thermal boundary condition is delivered by means of radiant panels in a manner consistent with the objectives described by Maluk, Bisby [39].…”

Section: Discussionmentioning

confidence: 99%

“…This experimental program employs a system of four radiant panels symmetrically positioned around concrete cylinders of 100mm in diameter and 200mm in height for thermal loading. This heating facility is capable of generating an essentially uniform heat flux level around the test specimens and thereby effectively overcoming the limitation of inconsistent thermal boundary conditions in conventional fire tests [38,39].…”

Section: Test Apparatus and Instrumentationmentioning

confidence: 99%

See 1 more Smart Citation

Application of digital image correlation system for reliable deformation measurement of concrete structures at high temperatures

Tran

Torero

et al. 2019

Engineering Structures

View full text Add to dashboard Cite

Reliable deformation measurement is required for proper quantification of fire performance of concrete structures. Predictive capability of models for many critical properties, including Young's moduli, stress-strain relationships and load-induced thermal strains, is first and foremost dependent on such reliable deformation capturing. This paper first presents a state-of-the-art review of existing methods for capturing deformation of concrete structures at elevated temperatures. Key merits, limitations and challenges associated with each measuring technique are discussed. It is shown that existing testing facilities and measuring instruments generally do not allow reliable direct measurement of displacement and strain of high-temperature concrete. As a result, the deformation has typically been captured either indirectly or outside the heated zones, inevitably introducing additional uncertainties and errors that are difficult to be adequately quantified. On the basis of that review, the paper details a new test setup for reliable, non-contact fullfield deformation capturing of concrete structures at high temperatures using 3D Digital Image Correlation technique. Key features of the new setup that enable to successfully address major challenges of thermal boundary condition, thermal stability of speckle pattern, contrast of image and hot air movement are highlighted. Evidence giving confidence to the reliability of the new setup are then presented, together with likely applications of such setup and their potential positive impact on the ongoing transitioning towards performance-based structural fire engineering.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Test Apparatus and Instrumentationmentioning

confidence: 99%

Application of digital image correlation system for reliable deformation measurement of concrete structures at high temperatures

Tran

Torero

et al. 2019

Engineering Structures

View full text Add to dashboard Cite

show abstract

“…Therefore, a non-contact method was required to record the deformation in the fibres while they were exposed. The challenges presented when DIC was used in similar test conditions (Ba Le et al, 2017), particularly in charring materials like timber and bamboo, added an extra difficulty to the use this sort of instrumentation.…”

Section: Analysis and Discussionmentioning

confidence: 99%

“…Due to the good agreement in the experimental observations, it was possible to establish a quadratic correlation between the distance from the panel and the sample and the incident heat flux, both with an R 2 of 1.00. This equation allows obtaining the incident heat flux on the beams if the distance between the panel and the beam is known, as was already presented by other authors (Le, Dao, Torero, Maluk, & Bisby, 2017). .21 shows the variation of the incident heat flux across the exposed area, for the different distances measured during the calibration.…”

Section: Thermal Boundary Conditionsmentioning

confidence: 92%

Fire analysis of load-bearing bamboo structures

González¹

View full text Add to dashboard Cite

The remarkable high strength-to-weight ratio of bamboo and the recent innovations and development of laminated bamboo products has enabled the potential for new larger and taller structural bamboo applications. However, there is little understanding of the behaviour and performance of bamboo structures during and after a fire. To date, bamboo has been used widely in low-rise constructions I am infinitely grateful with my amazing friends from the coffee, and beer club, Angela, Aaron, Juan Patricio, Ian, Luis, Sergio, Jaime, Andrea, Abed. I would not have completed this journey without your support and positive energy. They became like my family in Brisbane, and when I had to push uphill, they were always there to struggle with me, to motivate me, to make me grow, and make me laugh in the happiest and most difficult moments. My love and respect go to the UQ Fire family for their support, enlightening conversations, and diligent work.

show abstract

“…The above approach may require re-assessment [6]. It is questionable whether the materials' constitutive models developed based on test under minimised temperature gradients are representative of concrete in structures with substantial temperature gradients.…”

Section: Introductionmentioning

confidence: 99%

A study of temperature gradient effects on mechanical properties of concrete at elevated temperatures

Le¹

View full text Add to dashboard Cite

The outbreak of fire in a concrete structure can have serious consequences, including structural damage, loss of property, business interruption, and possibly loss of life. To ensure adequate fire performance of concrete structures, detailed knowledge of fundamental mechanical properties of concrete at elevated temperatures is crucial. In addition, realistic performance-based structural fire design, which has been developed in many countries (e.g. Australia, UK, New Zealand), requires detailed knowledge of fundamental properties of concrete at elevated temperatures to be re-examined in a holistic and scientific manner.Despite extensive research over the past decades, current knowledge of the fundamental properties of concrete at elevated temperatures remains primarily based on data collected from conventional tests in which inconsistent thermal boundary conditions are highlighted as limitations of the current testing method. In addition, the effect of temperature gradients has been intentionally minimised when determining the mechanical properties of concrete at elevated temperatures.Consequently, the influence of processes linked with temperature gradients, including thermal stress, moisture transport, and pore pressures, has not been directly addressed. This gap in knowledge is potentially important considering the steep temperature gradients formed within concrete structural members subjected to real fires.This thesis reports the outcomes of a research programme aimed at re-examining the performance of concrete in fire accounting for temperature gradients using a newly-developed testing method. This research has taken an integrated approach combining analytical, experimental, and numerical studies to investigate the effect of temperature gradients on mechanical properties of high strength concrete at the material level, focusing on a standard cylindrical concrete specimen (Ф100mm × 200mm).The outcomes of the thesis can be summarised as follow: -Analytical solution for evolution over time of in-depth temperature in a cylinder specimen subjected to a constant uniform heat flux boundary condition was obtained by solving the fundamental heat transfer equation. The analytical solution was demonstrated to agree well with numerical solutions using finite difference and finite element methods. This agreement gives confidence to the validity and reliability of the three approaches. Such validity of the models' predictions is then confirmed through their good agreement with the corresponding measured temperatures during testing of concrete cylinder specimens.ii -By heating using radiant panels, well-defined and consistently controlled heat flux boundary conditions on concrete cylinders (Ф100mm×200mm) were achieved. The repeatability, consistency, and uniformity of thermal boundary conditions were demonstrated using measurements of heat flux, temperature profile, and compressive strength. The newly-developed test setup enabled a more reliable study of the mechanical properties of concrete at elevated temperature...

show abstract

Effects of temperature and temperature gradient on concrete performance at elevated temperatures

Cited by 37 publications

References 12 publications

Application of digital image correlation system for reliable deformation measurement of concrete structures at high temperatures

Application of digital image correlation system for reliable deformation measurement of concrete structures at high temperatures

Fire analysis of load-bearing bamboo structures

A study of temperature gradient effects on mechanical properties of concrete at elevated temperatures

Contact Info

Product

Resources

About