Elevated-Temperature Performance, Combustibility and Fire Propagation Index of Fly Ash-Metakaolin Blend Geopolymers with Addition of Monoaluminium Phosphate (MAP) and Aluminum Dihydrogen Triphosphate (ATP)

Thermal performance, combustibility, and fire propagation of fly ash-metakaolin (FA-MK) blended geopolymer with the addition of aluminum triphosphate, ATP (Al(H2PO4)3), and monoaluminium phosphate, MAP (AlPO4) were evaluated in this paper. To prepare the geopolymer mix, fly ash and metakaolin with a ratio of 1:1 were added with ATP and MAP in a range of 0–3% by weight. The fire/heat resistance was evaluated by comparing the residual compressive strengths after the elevated temperature exposure. Besides, combustibility and fire propagation tests were conducted to examine the thermal performance and the applicability of the geopolymers as passive fire protection. Experimental results revealed that the blended geopolymers with 1 wt.% of ATP and MAP exhibited higher compressive strength and denser geopolymer matrix than control geopolymers. The effect of ATP and MAP addition was more obvious in unheated geopolymer and little improvement was observed for geopolymer subjected to elevated temperature. ATP and MAP at 3 wt.% did not help in enhancing the elevated-temperature performance of blended geopolymers. Even so, all blended geopolymers, regardless of the addition of ATP and MAP, were regarded as the noncombustible materials with negligible (0–0.1) fire propagation index.

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Effects of Sustained Elevated Temperature on Concrete Properties in Material Engineering and its Applications

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.578.154 ◽

2012 ◽

Vol 578 ◽

pp. 154-157

Author(s):

Hong Zhu Quan

Keyword(s):

Weight Loss ◽

Tensile Strength ◽

Compressive Strength ◽

Blast Furnace ◽

Elevated Temperature ◽

Fly Ash ◽

Blast Furnace Slag ◽

Concrete Properties ◽

Temperature Exposure ◽

Furnace Slag

This paper presents the results of experiment conducted to evaluate the effects of sustained elevated temperature on concrete. In this experiment, concrete with 4 types of cement, low-heat portland cement, blast-furnace slag cement and fly-ash cement were tested for strength without seal after sustained temperature exposure in the range of 20 to 300°C. Compressive strengths did not decline linearly with temperature and were minimal at around 50°C, showing 20% reduction, which associated with inter-mediate weight loss of 3%. Reductions in tensile strength and modulus of elasticity were greater than compressive strength.

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Effects of Elevated Temperatures on the Compressive Strength of HFCC

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.261-263.416 ◽

2011 ◽

Vol 261-263 ◽

pp. 416-420 ◽

Cited By ~ 1

Author(s):

Fu Ping Jia ◽

Heng Lin Lv ◽

Yi Bing Sun ◽

Bu Yu Cao ◽

Shi Ning Ding

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Fly Ash ◽

Room Temperature ◽

Elevated Temperatures ◽

Relative Strength ◽

Ordinary Concrete ◽

Residual Compressive Strength ◽

Fly Ash Concrete ◽

The Relationship

This paper presents the results of elevated temperatures on the compressive of high fly ash content concrete (HFCC). The specimens were prepared with three different replacements of cement by fly ash 30%, 40% and 50% by mass and the residual compressive strength was tested after exposure to elevated temperature 250, 450, 550 and 650°C and room temperature respectively. The results showed that the compressive strength apparently decreased with the elevated temperature increased. The presence of fly ash was effective for improvement of the relative strength, which was the ratio of residual compressive strength after exposure to elevated temperature and ordinary concrete. The relative compressive strength of fly ash concrete was higher than those of ordinary concrete. Based on the experiments results, the alternating simulation formula to determine the relationship among relative strength, elevated temperature and fly ash replacement is developed by using regression of results, which provides the theoretical basis for the evaluation and repair of HFCC after elevated temperature.

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Thermal Resistance of Fly Ash Geopolymers with Alumina as Additive

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.281.182 ◽

2018 ◽

Vol 281 ◽

pp. 182-188

Author(s):

Yong Sing Ng ◽

Yun Ming Liew ◽

Cheng Yong Heah ◽

Mohd Mustafa Al Bakri Abdullah ◽

Kamarudin Hussin

Keyword(s):

Elevated Temperature ◽

Fly Ash ◽

Thermal Resistance ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Room Temperature ◽

Strength Degradation ◽

Alumina Addition ◽

Higher Temperature ◽

Temperature Exposure

The present work investigates the effect of alumina addition on the thermal resistance of fly ash geopolymers. Fly ash geopolymers were synthesised by mixing fly ash with activator solution (A mixture of 12M sodium hydroxide and sodium silicate) at fly ash/activator ratio of 2.5 and sodium silicate/sodium hydroxide ratio of 2.5. The alumina (0, 2 and 4 wt %) was added as an additive. The geopolymers were cured at room temperature for 24 hours and 60°C for another 24 hours. After 28 days, the geopolymers was heated to elevated temperature (200 - 1000°C). For unexposed geopolymers, the addition of 2 wt % of alumina increased the compressive strength of fly ash geopolymers while the strength decreased when the content increased to 4 wt.%. The temperature-exposed geopolymers showed enhancement of strength at 200°C regardless of the alumina content. The strength reduced at higher temperature exposure (> 200°C). Despite the strength degradation at elevated temperature, the strength attained was relatively high in the range of 13 - 45 MPa up to 1000°C which adequately for application as structural materials.

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Research on Barite Concrete Mixed with Fly Ash

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.2107 ◽

2013 ◽

Vol 275-277 ◽

pp. 2107-2111

Author(s):

Qiu Lin Zou ◽

Jun Li ◽

Zhen Yu Lai

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Compressive Strength ◽

High Temperature ◽

Fly Ash ◽

Apparent Density ◽

Cycle Times ◽

Residual Compressive Strength ◽

Temperature Performance

Barite concrete with density grade of 3 and strength grade of C30 was prepared by mixing with different fineness of fly ash. The workability, mechanical properties and long-term high temperature performance of the prepared barite concrete were researched. Results show that the workability of barite concrete is improved by mixing with fly ash, and no segregation of mixture has been observed. The apparent density and 3d, 28d compressive strength of barite concrete are decreased obviously after mixing with fly ash. But with the increasing of the fineness of fly ash, the apparent density and 3d, 28d compressive strength of barite concrete have a slight increase. High temperature residual compressive strength is decreased with the increasing of temperature. The cycle times of heat treatment at 400°C only has a little effect on residual compressive strength of barite concrete.

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Elevated Temperature Performance of Surface Treated Nanostructured LiMn1.5Ni0.5O4 Spinel

ECS Meeting Abstracts ◽

10.1149/ma2008-02/6/568 ◽

2008 ◽

Keyword(s):

Elevated Temperature ◽

Temperature Performance ◽

Elevated Temperature Performance

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Investigation on Thermal Stability of Geopolymer Based Zeolite in Fire Case Study

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1009.31 ◽

2020 ◽

Vol 1009 ◽

pp. 31-36

Author(s):

Kanokwan Kanyalert ◽

Prinya Chindaprasirt ◽

Duangkanok Tanangteerapong

Keyword(s):

Weight Loss ◽

Compressive Strength ◽

High Temperature ◽

Fly Ash ◽

Alkali Activation ◽

Different Types ◽

Temperature Exposure ◽

In Fire ◽

Thermal Stability Of

This work aims to reveal the effects of zeolite on properties of fly ash based geopolymer under high temperature at 300 °C, 600 °C and 900 °C. The specimens were prepared by alkali activation of fly ash, which was partially replaced by two different types of zeolite at 10%, 20% and 30% by weight. The specimens were analyzed for the maximum compressive strength, weight loss percentage, XRD and SEM. The results highlighted that the percentage of weight loss increased with the ratio of zeolite replacement. The compressive strength of geopolymer with synthetic zeolite and natural zeolite at 7, 28, 60 days were similar. The high-temperature exposure resulted in the reduction in compressive strength in all proportions. At the same temperature, compressive strength of all specimens were not significantly different.

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