The influence of aggregate type on the physical and mechanical properties of high‐performance concrete subjected to high temperature

Abstract

Summary This paper presents the results of an experimental study on the behaviour of high‐performance concretes after high temperature exposure. The high temperature exposure is related to the potential risk of fire, and mechanical properties analysis is needed afterwards to assess the residual strength of the material. The results presented in the paper show the properties evolution of four concretes made with four different aggregate types: basalt, granite, dolomite and riverbed gravel. The mix compositions allow comparisons, because the cement paste and mortar compositions and their volumes remain the same for all the four concretes. Moreover, the aggregate particle size distribution was chosen to be quasi identical so that this factor does not affect the concrete behaviour. The decrease of tensile strength value with the increase of temperature is more pronounced than compressive strength reduction thus, the exponential and power function equations were proposed to describe ftT–fcT relationship. The change of modulus of elasticity in relative values is similar, although the initial values of modulus are different and correspond to the aggregate type. Copyright © 2015 John Wiley & Sons, Ltd.

Residual cube strength of coarse RCA concrete after exposure to elevated temperatures

“…An electrical furnace (internal dimensions of 45 cm long × 45 cm wide × 96 cm high) with the maximum temperature of 1200°C was employed in this study. Until now, the heating rates employed by different researches are rather different, which vary between 0.5°C/min and the ISO‐834 standard fire curve (greater than 100°C/min) . Related research shows that the heating rate ranging from about 1 to 10°C/min has marginally effect on the residual strength of concrete .…”

“…Until now, the heating rates employed by different researches are rather different, which vary between 0.5°C/min and the ISO-834 standard fire curve (greater than 100°C/ min). 20,21,[29][30][31][32][33][34] Related research shows that the heating rate ranging from about 1 to 10°C/min has marginally effect on the residual strength of concrete. 35 The heating rate of about 10°C/min was adopted in this study (see Figure 2), which was chosen based on prior studies 21,32 and the power of the electrical furnace.…”

Tối ưu hóa thành phần hạt tro xỉ nhiệt điện sử dụng làm cốt liệu cho bê tông chịu nhiệt

“…Các loại cốt liệu sử dụng cho BTCN cần phải thỏa mãn yêu cầu về độ bền nhiệt và tính ổn định thể tích cao, không bị phân hủy ở nhiệt độ cao, bảo tồn được cấu trúc của bê tông dưới tác dụng của nhiệt độ. Một số các nghiên cứu chỉ ra, để làm cốt liệu cho BTCN, người ta có thể sử dụng các vật liệu bền ở nhiệt độ cao (tùy theo nhiệt độ sử dụng) gồm các khoáng tự nhiên như đá bazan, điaba, điorít, quặng crômmít và các khoáng nhân tạo như keramzít, aglôporít, phế liệu gạch sa mốt, gạch đỏ; tro đáy, xỉ luyện kim [3][4][5][6][7].…”

Mechanical Properties

“…Felicetti and Gambarova (1998) presented tests based on the bending of HPC concrete prisms (beams), with and without notches, both hot and after cooling specimens down. The tensile strength was also investigated using a splitting test method by Noumowé et al (1996), Zhang et al (2000) and Hager et al (2014).…”