Geopolymer concrete has the potential to replace ordinary Portland cement which can reduce carbon dioxide emission to the environment. The addition of different amounts of steel fibers, as well as different types of end-shape fibers, could alter the performance of geopolymer concrete. The source of aluminosilicate (fly ash) used in the production of geopolymer concrete may lead to a different result. This study focuses on the comparison between Malaysian fly ash geopolymer concrete with the addition of hooked steel fibers and geopolymer concrete with the addition of straight-end steel fibers to the physical and mechanical properties. Malaysian fly ash was first characterized by x-ray fluorescence (XRF) to identify the chemical composition. The sample of steel fiber reinforced geopolymer concrete was produced by mixing fly ash, alkali activators, aggregates, and specific amounts of hook or straight steel fibers. The steel fibers addition for both types of fibers are 0%, 0.5%, 1.0%, 1.5%, and 2.0% by volume percentage. The samples were cured at room temperature. The physical properties (slump, density, and water absorption) of reinforced geopolymer concrete were studied. Meanwhile, a mechanical performance which is compressive, as well as the flexural strength was studied. The results show that the pattern in physical properties of geopolymer concrete for both types of fibers addition is almost similar where the slump is decreased with density and water absorption is increased with the increasing amount of fibers addition. However, the addition of hook steel fiber to the geopolymer concrete produced a lower slump than the addition of straight steel fibers. Meanwhile, the addition of hook steel fiber to the geopolymer concrete shows a higher density and water absorption compared to the sample with the addition of straight steel fibers. However, the difference is not significant. Besides, samples with the addition of hook steel fibers give better performance for compressive and flexural strength compared to the samples with the addition of straight steel fibers where the highest is at 1.0% of fibers addition.

In this paper, the development of fire-resistant geopolymers for the passive fire protection of buildings is investigated. The fire-resistant geopolymeric materials were based on the alkali activation of a metallurgical slag produced in primary copper industry with a highly alkaline solution of potassium hydroxide. In order to decrease the density of the developed geopolymers, their foaming or the addition of lightweight aggregates was also studied. The physical, mechanical and thermal properties of the developed materials were determined and their performance upon exposure to fire was tested according to the ISO-834 standard time-temperature curve, which is considered as appropriate for testing fire protection systems employed in buildings. During the whole test of the materials performance against fire, the temperature at the interface between concrete and geopolymer was recorded below 180 °C, as required by the ISO test followed, proving effectiveness for the developed materials to be used as a thermal barrier in buildings and constructions. After testing, the geopolymers kept their structural integrity, without presenting any significant macroscopic damage.

A filament winding system was developed for manufacturing various types of fiber/cement composite materials. In general, filament winding is a very popular method to produce composite parts which are axisymmetric such as composite pipes, tubes, tanks, cylinders, spheres that are fabricated using filament winding technique. In this study, raw material based geopolymer resin composites reinforced by continuous glass fiber were used for fabrication and synthesized by different types of raw materials which is fly ash, silica sand, white clay, kaolin and pozzolonic. The effects of different types of raw materials on the product were investigated. The compressive properties of the resulting composite were determined on an Instron Universal Testing under compression mode and the results shows white clay for vertical position gives the highest strength.

The preparation and characterization of glass reinforced epoxy filled with different weight percentage of geopolymers filler attained from fly ashand epoxy resins are reported limited of study. Recent glass reinforced epoxy pipe are reported exhibits relatively low mechanical properties, which limit their usage in structural applications and in oil and gas industrial. Thus, this restriction could be overcome through the formation of the addition of geopolymer fillers to improve their strength and toughness. The glass fiber was impregnated with different weight percentage and different molarity of fly ash-based geopolymer and epoxy hardener resin. Composite samples were made manually by filament winding technique and cured under room temperature. The sections perpendicular to the fibers and surfaces of the composites were analyzed by means of scanning electron microscope to estimate the adhesion between geopolymer matrices and fiber reinforcement. Relatively, wide range of geopolymer weight percentage from 10 % to 30 % at which can obtain high compressive properties, maximal values of compressive strength is 94.64 MPa and compressive modulus 2373.58 MPa for the sample with 30 % weight percentage of filler loading. These new composites materials show expressively enhanced mechanical properties if matched to straight glass reinforced epoxy pipe without any geopolymer filler. The positive mixture of synthetic method with the use of industrial by-products has acceptable fabricating novel low cost aluminosilicate binders, thanks to their suitable bondin contradiction of materials frequently used in structural application, could be used within the field of oil and gas industry.

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Foamcrete is fabricated by combining mortar slurry and constant foam. Owing to the existence of air entrained in its cementitious matrix, foamcrete is tremendously brittle compared to normal-strength concrete. The addition of synthetic and natural plant fibers demonstrates an enhancement to foamcrete’s mechanical performance yet exerts a harmful effect on long-term performance. Depreciation of natural plant fibers and corrosion of synthetic fibers impact the lifespan and durability properties of foamcrete. Hence, this study aims to investigate the mechanical properties and mode of failures of foamcrete reinforced with fiberglass mesh (FM). The parameters assessed were the compression, flexural, and splitting tensile strengths of 1100 kg/m3 density foamcrete confined with various layers of 145 g/m2 of FM. The optimal foamcrete mechanical properties enhancement was attained with three-layer jacketing. Notable augmentations of 108% in the compressive strength, 254% in flexural strength, and 349% in splitting tensile strength were achieved in comparison to the control specimens at day 28. The control foamcrete samples under compressive, flexural, and tensile loads encountered brittle failure in comparison to the confined foamcrete. The mode of failure under the tensile load indicates that only a slight crack occurred at the upper side and a perpendicular mark at the lateral section of the foamcrete with one to three layers of FM jacketing. Thus, the jacketing system of foamcrete with FM enhances the behavior and load carrying capacity of foamcrete to the extent of preventing the propagation of cracks.

In this study, the effect of geopolymer materials in epoxy hardener was studied under mechanical testing which is using flexural test. A series of epoxy filled with 10%-30% weight percentage geopolymer materials which are white clay, fly ash and silica sand was prepared. Flexural strength of the epoxy filled geopolymer materials is determined using Instron Universal Testing under flexural mode. It was found that the addition of these geopolymer materials into epoxy at the beginning with 10% weight percentage showing lower flexural strength than epoxy without geopolymer materials filled. However, flexural properties suddenly increased at 20% weight percentage of white clay and fly ash based geopolymer but tend to decrease at 30% weight percentage compared to silica sand based geopolymer which the strength is continue to decline with the increasing of weight percentage of silica sand. The results indicated that the blending of geopolymer materials in epoxy system can be obtained in this study.

This paper aims to find out the effect of different weight percentages of geopolymer filler in glass-reinforced epoxy pipe, and which can achieve the best mechanical properties and adhesion between high calcium pozzolanic-based geopolymer matrices. Different weight percentages and molarities of epoxy hardener resin and high calcium pozzolanic-based geopolymer were injected into the glass fiber. By manually winding filaments, composite samples were produced, and they were then allowed to cure at room temperature. To determine how well the geopolymer matrices adhere to the fiber reinforcement, the microstructure of the composites’ surfaces and perpendicular sections were examined. Maximum values of compressive strength and compressive modulus were 94.64 MPa and 2373.58 MPa, respectively, for the sample with a weight percentage of filler loading of 30 wt% for an alkali concentration of 12 M. This is a relatively wide range of geopolymer weight percentage of filler loading from 10 wt% to 40 wt%, at which we can obtain high compressive properties. By referring to microstructural analysis, adhesion, and interaction of the geopolymer matrix to glass fiber, it shows that the filler is well-dispersed and embedded at the fiber glass, and it was difficult to determine the differences within the range of optimal geopolymer filler content. By determining the optimum weight percent of 30 wt% of geopolymer filler and microstructural analysis, the maximum parameter has been achieved via analysis of high calcium pozzolanic-based geopolymer filler. Fire or elevated temperature represents one of the extreme ambient conditions that any structure may be exposed to during its service life. The heat resistance or thermal analysis between glass-reinforced epoxy (GRE) pipe and glass-reinforced epoxy pipe filled with high calcium pozzolanic-based geopolymer filler was studied by investigating burning tests on the samples, which shows that the addition of high calcium pozzolanic-based geopolymer filler results in a significant reduction of the melted epoxy.