Effect of Geopolymer Concrete Encased I-Section and Geopolymer CFST Column Under Fire

Geopolymer concrete can resist fire quite well when compared with conventional concrete. Recent studies to observe the behaviour of geopolymer composite column under the effect of fire are very few. In this paper results in terms of stress, strain and deformation of geopolymer composite column expressed to elevated temperature are presented. It was observed that geopolymer composite column performs better at elevated temperatures than the conventional composite column. This tests are performed with four composite column with geopolymer concrete and conventional concrete which is tested at four elevated temperatures i.e., 400 oC, 500 oC, 600 oC, 700 oC and 800 oC to evaluate the strength parameters. It results geopolymer concrete column can be used where fire disaster chances are high.

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Effect of Elevated Temperature on Mechanical Properties of High-Volume Fly Ash-Based Geopolymer Concrete, Mortar and Paste Cured at Room Temperature

Polymers ◽

10.3390/polym13091473 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1473

Author(s):

Jun Zhao ◽

Kang Wang ◽

Shuaibin Wang ◽

Zike Wang ◽

Zhaohui Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

Fly Ash ◽

Residual Strength ◽

Elevated Temperatures ◽

High Volume ◽

Sem Analysis ◽

Geopolymer Concrete ◽

Ordinary Concrete ◽

Exposure Temperature

This paper presents results from experimental work on mechanical properties of geopolymer concrete, mortar and paste prepared using fly ash and blended slag. Compressive strength, splitting tensile strength and flexural strength tests were conducted on large sets of geopolymer and ordinary concrete, mortar and paste after exposure to elevated temperatures. From Thermogravimetric analyzer (TGA), X-ray diffraction (XRD), Scanning electron microscope (SEM) test results, the geopolymer exhibits excellent resistance to elevated temperature. Compressive strengths of C30, C40 and C50 geopolymer concrete, mortar and paste show incremental improvement then followed by a gradual reduction, and finally reach a relatively consistent value with an increase in exposure temperature. The higher slag content in the geopolymer reduces residual strength and the lower exposure temperature corresponding to peak residual strength. Resistance to elevated temperature of C40 geopolymer concrete, mortar and paste is better than that of ordinary concrete, mortar and paste at the same grade. XRD, TGA and SEM analysis suggests that the heat resistance of C–S–H produced using slag is lower than that of sulphoaluminate gel (quartz and mullite, etc.) produced using fly ash. This facilitates degradation of C30, C40 and C50 geopolymer after exposure to elevated temperatures.

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Effect of Durability properties on Geopolymer concrete – A Review

E3S Web of Conferences ◽

10.1051/e3sconf/202018401092 ◽

2020 ◽

Vol 184 ◽

pp. 01092

Author(s):

M Niveditha ◽

Srikanth Koniki

Keyword(s):

Environmental Sustainability ◽

Elevated Temperatures ◽

Mineral Admixtures ◽

Geopolymer Concrete ◽

Conventional Concrete ◽

Curing Conditions ◽

Durability Properties ◽

Chemical Attack ◽

Strength And Durability ◽

Micro Structures

Geopolymer concrete is prepared by reacting silicate as well as aluminate consisting materials with a caustic activator. More often, waste materials such as GGBS, fly ash, slag from metal and iron production are used. Recent investigations adding new materials like Alccofine, which improves the properties of geopolymer concrete even at ambient temperature condition. This research paper presents a details literature survey on the durability properties of geopolymer concrete. Various research literatures are previewed on durability of geopolymer concrete with the addition of different supplementary cementious materials as their necessity is increasing due to insistent constituents. Past studies from the literature reviews suggested that replacement of cement with chemical and mineral admixtures enhanced the properties of strength and durability of concrete. The micro structures, Morphological structures by SEM, lower shrinkage, higher mechanical strengths, superior durability with environmental sustainability are observed. XRD studies shown enhanced polymerisation reaction which is responsible for development of strength. Elevated temperatures and Surface deterioration are controlled in GPC than OPC. Geopolymer concrete provides better resistance for specimens to chemical attack and also water absorption, sorptivity, porosity have good influence to the durability properties in ambient curing conditions compared to conventional concrete.

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Effect of Review elevated temperature on geo-polymer concrete – A Review

E3S Web of Conferences ◽

10.1051/e3sconf/202018401090 ◽

2020 ◽

Vol 184 ◽

pp. 01090

Author(s):

V Chandrakanth ◽

Srikanth Koniki

Keyword(s):

Elevated Temperature ◽

Elevated Temperatures ◽

Raw Materials ◽

Mineral Admixtures ◽

Polymer Concrete ◽

Alkaline Solutions ◽

High Temperature Strength ◽

Conventional Concrete ◽

Binder Type ◽

Fire Properties

The study on the effect of elevated temperature on Geo-polymer concrete (GPC) got its significance because conventional concrete start to deteriorate around 4000C. GPC gains attention as it is eco-friendly and economical, by utilizing industrial by-products. GPC also an alternate solution as the raw materials to produce cement are depleting day by day. GPC gains strength by geo-polymerization with the reactions between mineral admixtures and alkaline solutions. This paper presents the studies on general properties and advantages of GPC over conventional concrete which depend on properties of binder, type of curing etc. Current study mainly concentrates on effect of elevated temperatures and post fire properties of GPC depending upon rate of heating, duration of fire and maximum high temperature. Strength and durability recovery of fire damaged concrete is discussed.

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Properties of Fly Ash Based Geopolymer Concrete Exposed to Sustained Elevated Temperatures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.962 ◽

2011 ◽

Vol 250-253 ◽

pp. 962-968 ◽

Cited By ~ 3

Author(s):

M.S. Sudarshan ◽

R.V. Ranganath

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Elevated Temperature ◽

Fly Ash ◽

Elevated Temperatures ◽

Research Work ◽

Acid Resistance ◽

Geopolymer Concrete ◽

Cement Concrete ◽

Beneficial Effects

Fly ash based geopolymer concrete is gaining importance in the context of developing alternatives to cement concrete. The research work available in the literature shows many beneficial effects of the material in terms of its high early compressive strength, tensile strength, reduced shrinkage, good acid resistance etc., However, there are very few studies carried out on the influence of sustained elevated temperature on the properties of geopolymer concrete. This paper presents the results of some of the properties of fly ash based geopolymer concrete activated using sodium silicate and sodium hydroxide and subjected to elevated temperature at 150°C, 200°C, 300°C, 400ºc under sustained durations of 1 hour, 2 hours and 4 hours. The results show that residual compressive strength is about 20% less than the normal at about 200°C itself possibly due to the development of vapour pressure formed by the non-reactive water present in the system. Beyond 2 hours of sustenance, there is not much of a difference in the properties of concrete.

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Performance of metakaolin based geopolymer concrete at elevated temperature

Nigerian Journal of Technology ◽

10.4314/njt.v39i3.11 ◽

2020 ◽

Vol 39 (3) ◽

pp. 732-737

Author(s):

S. Gambo ◽

K. Ibrahim ◽

A. Aliyu ◽

A.G. Ibrahim ◽

H. Abdulsalam

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Water Absorption ◽

Abrasion Resistance ◽

Elevated Temperatures ◽

Carbon Dioxide Emission ◽

Geopolymer Concrete ◽

Aggressive Environment ◽

Electric Oven ◽

Metakaolin Geopolymer

Due to the carbon dioxide emission arising from the production of cement, alternative concrete that is environmentally friendly such as metakaolin geopolymer concrete have been developed. However, the performance of metakaolin based geopolymer concrete (MKGC) when exposed to aggressive environment particularly elevated temperature has not been investigated. Therefore, this paper assessed the performance of MKGC exposed to elevated temperatures. MKGC cube specimens of grade 25 were produced using a mix ratio of 1:1.58:3.71.After preparing the specimens, they were placed in an electric oven at a temperature of 60oC for 24 hours. Thereafter, the specimens were stored in the laboratory at ambient temperature for 28 days. The specimens were then exposed to elevated temperatures of 200, 400, 600 and 800oC. After exposure to elevated temperatures, the MKGC specimens were subjected to compressive strength, water absorption and abrasion resistance tests. Results show that at 600 and 800oC, the MKGC lost a compressive strength of 59.69% and 71.71% respectively. Higher water absorption and lower abrasion resistance were also observed. Keywords: Cement, Compressive Strength, Metakaolin Concrete, Elevated Temperature.

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Development of Test Equipment for Measuring Compression Characteristics of Sheet Gaskets at Elevated Temperature

Volume 2: Computer Applications/Technology and Bolted Joints ◽

10.1115/pvp2007-26382 ◽

2007 ◽

Cited By ~ 1

Author(s):

Toshimichi Fukuoka ◽

Masataka Nomura ◽

Yoshihiko Hata ◽

Takashi Nishikawa

Keyword(s):

Elevated Temperature ◽

Compression Test ◽

Elevated Temperatures ◽

Testing Procedure ◽

Great Difficulty ◽

Test Equipment ◽

Experimental Point ◽

Stress Strain ◽

Sealing Performance ◽

Compression Characteristics

Evaluation of the sealing performance of pipe flange connection is significantly important for the safety of pipe line structures. The compression characteristics of sheet gaskets primarily affect the mechanical behavior of flanged connections. It is known that the stiffness of sheet gaskets decreases with an increase in temperature. Therefore, the compression test must be conducted at various levels of elevated temperatures. From the experimental point of view, however, a great difficulty is involved in measuring the compression characteristics of gaskets at elevated temperature. For this reason, a definite testing procedure has not yet been established. In this paper, a prototype of compression test equipment has been developed for measuring the stress-strain curves of sheet gaskets at elevated temperature. The test equipment is compact and the experiments can be conducted with a fairly easy operation. It can control the gasket stress from zero to 30MPa while keeping the temperature of test specimen at different levels from room temperature to 300° C and higher. Aramid sheet gaskets are selected as test specimens. Experimental results show that the gasket stiffness drops with an increase in temperature. The shapes of the compression curves at different temperatures are similar, and those curves move in the direction of lower stiffness as the temperature is increased. It is concluded that the test equipment proposed here has a high promise to measure the stress-strain curves of sheet gaskets and estimate the sealing performance of pipe flange connections at elevated temperature.

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Experimental investigations on compressive, impact and prediction of stress-strain of fly ash-geopolymer and portland cement concrete

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0036 ◽

2020 ◽

Vol 40 (7) ◽

pp. 583-590

Author(s):

Nagajothi S ◽

Elavenil S

Keyword(s):

Portland Cement ◽

Ordinary Portland Cement ◽

Impact Resistance ◽

Geopolymer Concrete ◽

Portland Cement Concrete ◽

Cement Concrete ◽

Stress Strain ◽

River Sand ◽

Conventional Concrete ◽

Strain Behaviour

AbstractThe recent technology of geopolymer concrete is a substitute material for ordinary portland cement concrete which is produced from the polycondensation reaction of aluminosilicate materials with alkaline activator solutions. The cost of river sand is high since the demand for the same is also high. Manufactured sand is used as a replacement material for river sand in geopolymer concrete. This paper mainly focuses to find the properties of fly ash (FA) – based geopolymer concrete under ambient cured temperature like compressive strength, stress strain behaviour, modulus of elasticity, Poission’s ratio and impact resistance. The result of geopolymer concrete is compared with ordinary portland cement concrete. The elasticity modulus and Poission’s ratio of geopolymer concrete are lower than conventional concrete. The Stress-strain behaviour of geopolymer concrete is similar to conventional concrete. The impact resistance of geopolymer concrete is very good when compared with conventional concrete.

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Temperature Dependent Plastic Deformation Behavior of AZ31 Magnesium Alloy in Uniaxial and Biaxial Compressions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.725.421 ◽

2016 ◽

Vol 725 ◽

pp. 421-426 ◽

Cited By ~ 1

Author(s):

Ichiro Shimizu

Keyword(s):

Elevated Temperature ◽

Flow Stress ◽

Magnesium Alloy ◽

Magnesium Alloys ◽

Deformation Behavior ◽

Room Temperature ◽

Elevated Temperatures ◽

Temperature Dependency ◽

Stress Strain ◽

Stress Strain Relation

Metal forming of magnesium alloys often performed at elevated temperature, because magnesium alloys exhibit peculiar stress-strain relation and inferior ductility compared to conventional metals at room temperature. In the present study, deformation behavior and formability of cast and extruded AZ31 magnesium alloys under uniaxial and biaxial compressions at room temperature and at elevated temperatures were investigated. The results revealed that the compressive stress-strain relation of AZ31 magnesium alloy changed not only with the initial texture but also with the deformation temperature. The temperature dependency of flow stress of the cast alloy was smaller than that of the extruded alloy probably because of less influence of pre-deformation. In addition, the influence of compressive deformation pattern upon flow stress of the extruded alloy remained even at elevated temperature to 523 K. The temperature dependency of compressive fracture was also discussed and it was found that the equi-biaxial condition improved the compressive formability at elevated temperatures.

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Durability and Damage Development in Woven Ceramic Matrix Composites Under Tensile and Fatigue Loading at Room and Elevated Temperatures

10.1115/imece1999-0508 ◽

1999 ◽

Author(s):

Anwarul Haque ◽

Md. M. Rahman ◽

Hisham T. Mohamed ◽

Hassan Mahfuz ◽

Uday K. Vaidya ◽

...

Keyword(s):

Elevated Temperature ◽

Cyclic Loading ◽

Elevated Temperatures ◽

Failure Strain ◽

Ceramic Matrix Composites ◽

Matrix Cracking ◽

Woven Composites ◽

Damage Development ◽

Stress Strain ◽

Damage Initiation

Abstract This paper investigates the damage development in SiC/SiNC woven composites under tensile and cyclic loading both at room and elevated temperatures. The ultimate strength, failure strain, proportional limit and modulus data at a temperature range of 23°C–1380°C are generated. The tensile strength and the modulus of SiC/SiNC woven composites have been observed to decrease insignificantly with increased temperatures beyond the linear portion of the stress/strain plot. The stress/strain plot shows a pseudo-yield point at 25% of the failure strain (εf) which indicates damage initiation in the form of matrix cracking. The evolution of damage beyond 0.25 εf both at room and elevated temperature comprises of multiple matrix cracking, interfacial debonding and fiber pullout. Although the nature of the stress/strain plot shows damage-tolerant behavior under static loading both at room and elevated temperature, the life expectancy of SiC/SiNC composites degrades significantly under cyclic loading at elevated temperature. This is mostly due to the interactions of fatigue damage caused by the mechanically induced plastic strain and the damage developed by the creep strain. The in situ damage evolutions are monitored by acoustic event parameters, ultrasonic C-scan and stiffness degradation.

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Study on Effect of Superplasticizer on GGBS Blended Geopolymer Concrete

Energy and Earth Science ◽

10.22158/ees.v2n2p45 ◽

2019 ◽

Vol 2 (2) ◽

pp. p45

Author(s):

Vahini M. ◽

K. Manjunatha ◽

Venkatesh ◽

Basappa Meti

Keyword(s):

Fly Ash ◽

Waste Product ◽

Embodied Energy ◽

Geopolymer Concrete ◽

Strength Parameters ◽

Conventional Concrete ◽

Binding Material ◽

Alumino Silicate ◽

Alkaline Activator ◽

Source Materials

Geopolymer concrete is an alternate to conventional concrete with reduced carbon emission, embodied energy and global warming potential and transforming waste product into an useful material. Geopolymer concrete is produced by mixing highly alkaline activator solution with alumino silicate source materials. Geopolymer concrete is highly viscous or sticky in nature, to overcome this drawback, an attempt has been made to study the effect of naphthalene based superplasticizer on geopolymer concrete blended with GGBS. Fly ash was replaced by GGBS at 20% increment levels, keeping a constant superplasticizer dosage at 3% by weight of binding material. Workability and strength characteristics were compared with those of geopolymer concrete blended with GGBS without superplasticizer. Up to certain replacement level of fly ash with GGBS, results in decrease of strength parameters with increase in workability, further replacement results in increase of strength with reduced workability with the addition of superplasticizer.

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