Glass Fibre Reinforced Cement Research Articles

Flexural behavior of glass fiber reinforced cement incorporating foam

Glass fiber reinforced cement (GRC) incorporating foam has good thermal insulation. Micro pores not only lowered the strength of the cement matrix but also changed the friction between the fiber and the matrix. It has an influence on modulus of rupture (MOR) and fracture energy of GRC. In this work, the effect of the glass fiber and foam contents of GRC on the MOR and fracture energy were evaluated using four-point flexural tests. The results show that glass fiber content has little influence on MOR of GRC. However, the MOR decreased significantly with increasing foam content. The empirical formula summarized by experiments can well characterize the relationship between the MOR and density of foamed GRC. The content of glass fiber and foam has a significant influence on the fracture energy of GRC. The fracture energy of foamed GRC decreased with the decrease of dry bulk density, and the decrease was fast and then slow.

Community assistance in the utilization of palm coir fiber

The community assistance program in utilizing oil palm coir in Kolaka Regency, Southeast Sulawesi for supporting materials from the GRC mixture is a new breakthrough in the use of palm coir waste. This activity is expected to overcome the problem of oil palm coir waste and make it a new economic source for the surrounding community. The purpose of this program is to increase public knowledge in utilizing palm oil coir waste so that it can be of economic value and to increase public understanding in the process of making GRC by utilizing palm coir waste. The method used is assistance in the utilization of palm coir fiber as an added material in the manufacture of GRC plates. The results of the monitoring and evaluation activities resulted in the response that the surrounding community could process palm oil coir waste into a commodity that has economic value and additional knowledge to utilize palm oil coir waste in the manufacture of Glassfiber Reinforced Cement (GRC) as part of innovation in the construction sector.

An Assessment of External Wall Retrofitting Strategies Using GRC Materials in Hot Desert Regions

Due to urbanization, population growth, and the consequences of climate change, the usage of energy for cooling has increased considerably in recent years. Passive climate measures, on the other hand, could alleviate the situation by reducing energy use in buildings. This study examined the environmental and financial benefits of utilizing glass fiber-reinforced cement in the external walls of a communal social hub building in New Aswan city, taken an example of the hot desert region. Utilizing Design Builder software, the effect of various outside wall alternatives on cooling energy consumption was explored and analyzed. In addition, a cost–benefit analysis utilizing the simple payback period was conducted to aid decision-makers in selecting the most suitable exterior wall materials for public buildings in hot desert regions. Using cement plaster, cement brick, glass wool, and glass fiber-reinforced cement as an outside wall resulted in a significant improvement rate, according to the data. Compared to a typical wall (cement plaster, cement brick, and cement plaster), it can save up to 41% of energy. In addition, it has the lowest simple payback period value when compared to other examined solutions (10.86 years). In general, the results indicate that glass fiber-reinforced cement walls embedded in thermal insulation materials and incorporated into cement brick walls are more energy-efficient in terms of necessary cooling energy and economic viability.

Thermal Behaviour and Micro Climate Studies of Several Wall Insulation on Houses in a Tropical Climate (Aw) Area

Standard brick walls have caused a gradual increase in the area’s temperature due to the bricks’ emissivity. Therefore, several effective technologies to overcome this problem have been proposed, one of which is thermal insulation by covering the outer walls of bricks from exposure to sunlight. This study compares thermal insulation effectiveness with Glass Fiber Reinforced Cement (GRC) and Expanded Polystyrene (EPS) material to obtain better insulations. This study is performed by modeling the area of 4 housing units using ENVI-met V4 in a humid tropical climate, focused in an east-west direction in a clear sky. Each building measures eight times 6 m2, with 4 meters in height, with a distance between buildings of 3 meters. GRC and EPS are affixed to the entire surface of the outer wall of the building, both on the east side and west sidewalls. The parameter observed is the wall surface temperature. The results showed that walls with GRC and EPS gave more effective results in lowering the surface temperature of brick walls, with values ranging from 8-23%. The use of insulation intervention on the east wall at 06.00-12.00 and the west wall at 13.00-18.00 shows higher accumulated surface temperature than the standard brick wall at peak hours, which means that the insulation material controls solar radiation. However, the phenomenon on the east wall at 12.00-07.00 and the west wall at 18.00-13.00 shows a controlled temperature above the surface temperature when using a standard brick wall.

Durability of Glass Fiber Reinforced Cement (GRC) Containing a High Proportion of Pozzolans

Glass fiber reinforced cement (GRC) is an excellent composite for architects and engineers because it can be molded to produce laminar panels or to create complicated designs. GRC is a fine concrete reinforced with alkali-resistant glass fibers at 3–5% per mass. However, fiber durability is limited because of the aggressiveness of the alkaline medium produced during Portland cement hydration (effect of portlandite). The objective of this study is to assess GRC with high Portland cement replacement with pozzolans (ground fly ash or a mixture of ground fly ash and sonicated silica fume) in order to reduce the corrosion of the fibers. The selected high-content pozzolan (60% replacement) composites were tested under different conditions: aging, drying–wetting, freezing–thawing, and chemical attack (ammonium chloride and sulfuric acid). The modulus of rupture and toughness were determined. Composite behavior showed that the samples with pozzolans not only better resisted aging, but also physical and chemical attacks, and specimens presented a better modulus of rupture and toughness than the samples prepared with 100% Portland cement (control specimens). Due to the good behavior in durability terms, the high pozzolan content GRC products are suitable in potential corrosive environments for sunscreens, drainage channels, cable trays, sound barriers, or pavements.

Effect of fiber content on bending performance of glass fiber reinforced cement slab

To investigate the effect of fiber content on the bending properties of oriented glass fiber reinforced cement (GRC), the four-point flexural test was used to get the fracture performance of oriented GRC slab, and a 3D numerical model is created by RFPA^3D simulation software.The failure modes of the GRC slab with different glass fiber content are compared.The load-displacement curve of the specimen is analyzed, and the strengthening and toughening effect of the fiber is investigated by fracture energy. The results show that the peak load of the specimens enhances with the increase of the oriented fiber within volume fraction of 0.5% and 2.0%. The specimen with added fibers still has a certain bearing capacity when cracks appear at the bottom, and the fibers are damaged but not broken. With the increase of fiber content, the crack propagation path becomes more tortuous, the more work is done when failure occurs, and the better the toughness is. The study can provide a reference for reinforcement of directional GRC.

Influence of Natural Weather Conditions in the Long-Term Fracture Energy of Glass Fibre Reinforced Cement (GRC) Modified with Chemical Additions.

The use of glass fibre-reinforced cement (GRC) in structural elements has been limited due to the reduction in the mechanical properties of the material with aging. Chemical additions have been used to modify the cement mortar formulation in order to minimise such loss, but no conclusive results have been obtained yet. Moreover, the application of accelerated aging methods in such modified GRC formulations still poses several uncertainties. An experimental campaign seeking to assess the reduction in the fracture energy of two GRCs manufactured with modified matrixes after five years of exposure to natural environment was performed. Furthermore, a comparison with results from the literature that used accelerated aging methods was performed. The results show that the use of the chemical additives might be capable of maintaining to a notable extent the mechanical properties of GRC after five years of natural aging. Regarding the accelerated aging method by means of immersion in hot water tanks, it seemed that the equivalences applied in previous research accurately match the degradation of the material after natural exposure to weather. Additionally, a digital image correlation analysis showed that aged GRCs seemed to distribute damage in a smaller area than young GRCs.

The Comparison of Energy Usage of Modular Housing using Sefaira®

As the fourth largest population in the world with 52% urban inhabitant, housing as the most primer need, Indonesia has a significant impact on urban energy consumption. The backlog of housing in the urban area is known as much as 8%. The government tries to fulfill those needs by supplying an affordable house that requires not more than 36m2 and less than IDR 121 million The need for affordable housing occupies the largest ratio in urban areas. This is related to the middle-class family’s income structure that 21% of the total population of Indonesia. The complexity in modular affordable house design that derives from the building material, construction cost, as well as the energy consumption, later becomes the urgency of this study. This paper aims to compare simulating several modular houses with 36m2 total ground floor area, namely: 6m x 6m, 4m x 9m, and 3m x 12m module houses using metal wall cladding and Glassfibre Reinforced Cement (GRC). From these comparisons will be found modular house designs and material that have optimal energy efficiency. This paper presents modular house design. The modular house design will recommend which modules and materials will best optimize the building’s performance, thus optimizing energy efficiency based on the simulation results. Based on each material’s U-Value, a house with a GRC wall has lower energy consumption than a house with metal wall cladding because GRC has a lower U-Value.

Sefaira Simulation in Residential Houses to Determine the Energy Use of Wall Materials

Wall material popularly used in Indonesia is a masonry wall, where the process takes longer than prefabrication wall materials or houses built-in components such as panels or modules. In this study, four types of prefabrication wall materials will be analyzed based on the annual energy use of each material. The wall materials chosen are Hebel, Alderon, Glassfibre Reinforced Cement Board (GRC), and metal deck. The calculation of energy consumption uses a simulation of a 27 m2 one-floor residential building located in Bandung City, West Java, Indonesia. Furthermore, the simulation is analyzed with Sefaira software based on ASHRAE 90.1 - 2013. From the results of this Sefaira analysis, it is obtained that the Energy Use Intensity (EUI) value for Hebel wall material is 58 kWh/m2/yr, Alderon wall 90 kWh/m2/yr, Glassfiber Reinforced Cement Board (GRC) 83 kWh/m2/yr, and metal deck 89 kWh/m2/yr. Among the four recommended prefabricated wall materials, Hebel materials are considered to have the least energy use. Meanwhile, the EUI target of the 2030 Challenge for residential houses is 38 kWh/m2/yr, so it must reduce as much as 45 kWh/m2/yr for Hebel material.

Effect of Low Temperatures on the Mechanical Performance of GFRC Modified by Low Carbon Cement

Glass fibre reinforced cement (GFRC) is a composite material with great ductility but it undergoes severe strength and ductility degradation with ageing. Calcium sulfoaluminate (CSA) cement is low carbon cement, and more importantly, it exhibits great potential to produce more ductile and durable GFRC. This study focuses on mechanical performance, e.g., compressive strength, stress‐strain curve, and freeze‐thaw resistance of CSA/GFRC as well as its microstructural characteristics under low temperatures. XRD was applied to investigate the hydration mechanism of CSA cement under −5°C, 0°C, and 5°C. It was found out that low‐temperature environments have very little effect on the type of hydration products, and the main hydration product of hydrated CSA cement cured under low temperatures is ettringite. Moreover, low‐curing temperatures have an adverse effect on the compressive strength developments of CSA/GFRC but the strength difference compared with that under 20°C reduces gradually with increasing curing ages. In terms of bending performance, both ultimate tensile strength and ultimate strain value indicate considerable degradation with ageing under low temperatures after 14 d. The ultimate strain value reduces to 0.34% at −5°C, 0.39% at 0°C, and 0.44% at 5°C compared with 0.51% for that cured at 20°C for 28 d. The tensile strength of samples cured at −5°C for 28 d is only 15.2 MPa, taking up only 40% of that under 20°C. CSA/GFRC also demonstrated great capability in the antifreeze‐thaw performance, and the corresponding strength remains 95.9%, 94.7%, 94.2%, and 94.3%, respectively, for that cured under 20°C, 5°C, 0°C, and −5°C after 50 freeze‐thaw cycles. Microstructural studies reveal that densification of the interfilamentary space with intermixtures of C‐A‐S‐H and ettringite is the main reason that causes the degradation of CSA/GFRC, which may result in loss on flexibility when forces are applied, therefore reducing the post‐peak toughness to some extent.

New Anticracking Glass‐Fiber‐Reinforced Cement Material and Integrated Composite Technology with Lightweight Concrete Panels

Glass‐fiber‐reinforced cement (GRC) is a widely used decorative material for wall facades. Conventional GRC products have poor crack resistance, low construction efficiency, poor integration, and few environmental benefits, hence failing to meet the requirements of building industrialization. To realize an integrated composite wall made from GRC and precast lightweight concrete (PLC) with a lasting anticrack effect, the anticracking properties of GRC material as well as the connection mode of GRC and PLC layers were studied. Through long‐term shrinkage test, the influence of fiber content, rubber powder content, and expansion agent content on the crack resistance of GRC material was systematically analyzed. At the same time, the influence of connection mode on the crack resistance of the GRC layer after compositing with precast lightweight concrete (PLC) was analyzed. The results showed that adding fiber can effectively improve the flexural strength of the GRC and reduce drying shrinkage, whereas adding rubber powder can effectively improve its toughness and crack resistance. The addition of U‐type expansion agent (UEA) can impart the cement mortar with a certain degree of microexpansion performance and help improve the drying shrinkage of the GRC. Compared with other compounding methods, the smooth connection of the GRC and PLC can effectively reduce the shrinkage of the GRC surface layer and improve its crack resistance. So, the new GRC material has good crack resistance performance and facade effect. These research studies provide an experimental basis for the large‐scale application of the panel, and it has great advantages in improving the efficiency of prefabricated building construction.

Application of Glass Fiber Reinforced Composite Materials in Construction Engineering

Glass fiber reinforced cement (GRC) is a new type of composite material formed by using alkali-resistant glass fiber as a reinforcing material and cement paste or cement mortar as a matrix. GRC is widely used in construction engineering. However, the durability of GRC is still a major problem in engineering applications, especially GRC materials have been in the hot and humid building engineering environment for a long time. The alkaline environment of the cement matrix will cause serious erosion of the glass fiber, and Will significantly reduce the mechanical properties such as flexural strength and toughness of GRC. In this paper, ordinary Portland cement is mixed with active mineral admixtures such as fly ash and silica fume to reduce the alkaline environment of GRC matrix, and to delay the erosion rate of glass fiber and increase the flexural strength and compressive strength of GRC; At the same time, the effects of different hot and humid building engineering environments on the mechanical properties of GRC were studied.

Study on in-situ modification of poly-dopamine on glass fibers and its effect on shrinkage performance of cement materials

Cement-based materials are one of the essential construction materials that had been widely used in infrastructure and facilities. However, it experienced shrinkage problems, which led to the cracking of concrete buildings and deterioration of the durability. The incorporation of glass fibers can improve the shrinkage resistance of cement materials by enhancing the interface between cement and fiber. Aiming at improving the shrinkage resistance of cement, in this study, glass fibers were in-situ modified with poly-dopamine in aqueous solution. The effect of dopamine hydrochloride concentration and the pH of the solution were investigated with the optimal condition attained to be 2×10−3 g/ml and 8.5, respectively. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy analysis (XPS) were utilized for the characterization of as-prepared poly-dopamine modified glass fibers. Subsequently, as-prepared and untreated glass fibers were mixed with cement at varied volume fraction and water-cement ratio for the study of shrinkage performance. The glass fiber-reinforced cement had a lower shrinkage than cement without glass fibers. Compared with the cement without glass fibers, when the water-cement ratio was 0.4 and the volume content of in-situ modified glass fibers of poly-dopamine was 7%, the reduction in 28-day shrinkage of poly-dopamine in-situ modified glass fiber-reinforced cement was large extent, reducing by 42%. The shrinkage resistance performance of in-situ modified glass fibers reinforced cement with poly-dopamine was better than that of untreated glass fibers. In short, this work developed novel approach for in-situ modification of glass fibers and found a new path to improve the shrinkage resistance of cement material.

The Innovation of Glassfiber Reinforced Cement (GRC) Application in Buildings

One example of the innovation in building construction that is expansively used at present is Glassfiber Reinforced Cement (GRC). GRC is a cement product based on material mixed with fiberglass. GRC is one of the developments of concrete. This product easily and efficiently provides solutions to a variety of building designs. Additionally, its various forms can be applied to numerous types and functions of buildings. This research aimed to identify the suitability of GRC for several functions. The methods in this study employed a type of qualitative research, with data collection techniques in the form of observation and documentation in several examples of buildings that applied the GRC material innovation. Data analysis was obtained from observation related to GRC types, sizes, installation techniques, and functions in the building. Results showed that the GRC had various types, shapes, and sizes. It could be applied to the building exterior or interior. Each building used different GRC specifications tailored to meet needs and design of the building. GRC installation techniques could use the frame or without frames, adapted to the needs and types of GRC used

Study on the time-dependent mechanical properties of glass fiber reinforced cement (GRC) with fly ash or slag

The mechanical properties change law of glass fiber reinforced cement (GRC) with fly ash or slag after natural curing for 28, 180, 360 days and accelerated aging at 80 °C for 8 days were studied respectively. Besides the degradation mechanism were discussed. It was found that GRC naturally cured for 28 days exhibited good flexural toughness regardless of mineral admixtures. After natural curing for 180 days, there was no chemical corrosion of glass fiber in GRC, and modulus of rupture (MOR) of GRC increased at the same time, but the loss of fracture energy was more than 50%, and GRC became brittle under the flexural condition. At the age of 360 days, slight chemical corrosion occurred in glass fibers in GRC; and after 8 days of accelerated aging, severe chemical corrosion was observed. However, in these two cases the fracture energy of GRC was similar to that of GRC with the same mix proportion of natural curing to 180 days. The time-dependent deviation of fracture energy can reflect the degradation of GRC performance more precisely than that of MOR. Fly ash and slag may possess the ability of inhibiting the chemical corrosion of glass fibers in GRC according to test results, but the chemical corrosion of glass fibers is not the main reason for the decrease of GRC fracture energy. The key deterioration factor of GRC performance is the strong bonding of glass fibers with hydrates of cementitious materials which lead to fiber breakage rather than fiber pull-out.

The Bond Response of Concrete Brick with Recycled Tire Chip as Partial Replacement of Aggregate Applied in the Non-Structural Masonry Wall

The walls of buildings are made from several types of materials, including red and concrete bricks, glass fiber-reinforced cement, wood and glass. Concrete brick has many advantages. It is relatively cheap, with more economical mortar usage and it has an easier and faster installation. Unfortunately, the main disadvantage of concrete brick is that it is heavier than many other wall building materials. In order to reduce the weight of concrete brick as well as to dispose waste tire safely, the objective of this study is to investigate the mechanical effect of the application of recycled tire as a partial replacement of aggregates in the concrete brick. The application of recycled tire in concrete brick with high volume protects the environment from pollution due to the waste tire. The dimension of concrete brick is 345 mm of length, 90 mm of width and 100 mm of thickness. The recycled tire utilized in the study is in the form of chips with dimensions of 4 mm × 4 mm × 20 mm. The chips are mixed with mortar in order to form the concrete brick. The content of recycled tire chips in concrete brick without superplasticizer is 0, 15, 30, 45 and 60% and with superplasticizer it is 0%, 50%, 55%, 60%, 65%, 70% and 75% by volume. Several types of testing for concrete brick with recycled tire are carried out, focusing on the unit weight, the compressive strength, the flexural strength and the shear strength. It has been found out that concrete brick containing 75% of recycled tire chips reduces the unit weight of concrete brick by ~63% compared to concrete brick without recycled tire chips. Moreover, the highest compressive, flexural and shear strengths are 1.32 N/mm2 for concrete brick with 50% of recycled tire, 0.063 MPa for concrete brick with 55% of recycled tire and 0.064 MPa for concrete brick with recycled tire content of 65%.

Research on the Application of GRC Material in Exhibition Decoration Engineering

Glass fiber reinforced cement (GRC) is a kind of new building material which is based on cement and take the alkali resistant glass fiber as reinforcing material. It is mainly used in building decoration project and it has many advantages like environmental protection, economical, practical modeling and others. This paper mainly studies the concrete application of GRC material in exhibition building decoration project.

Enhancement of durability of glass fiber-reinforced cement with PVA

The main thrust of this research was to determine the effectiveness of polyvinyl alcohol (PVA) powder in enhancing the durability of short GFRC materials. Accelerated aging of the materials was achieved through low-pressure steam curing in a moist chamber. The strength and ductility of GFRC were measured by the direct tension test, which showed that incorporation of PVA powder into GFRC could improve its mechanical behaviour and turn it from brittle to ductile. To investigate the mechanism of the tensile strength enhancement, the fiber-matrix interface was examined by polarizing optical microscopy and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDAX). It was found that PVA powder tended to migrate to the fiber-matrix interfacial zone and thus prevented the accumulation of calcium hydroxide in this area. PVA film around the fiber resulted in a more ductile interfacial microstructure and better bonding between fiber and matrix, which should be responsible for enhancing the tensile property and preventing the aging of GFRC. Furthermore, PVA powder reduced the microhardness and brittleness at the interface.

Ultrasonic broadband signals monitoring of glass-fiber reinforced cement (GRC) bending tests

In this study, complete ultrasonic monitoring of Glass-fiber Reinforced Cement plates under bending tests was addressed. In this kind of experiment, the mechanical properties of the specimen continuously change during the test, thus, the acquisition time of the ultrasonic signals is a critical variable. In order to overcome this drawback, a new ultrasonic procedure based on broadband signals (chirp) has been applied. Following this line of thought, the analysed ultrasonic parameters have been split into the parameters that only depend on time, and those that depend on both time and frequency. In particular, the frequency dependent attenuation parameter allows characterizing the evolution of the plate being damaged over a wide frequency range and significantly detecting the main two events happening during the experiment: the first crack and the maximum stress point. In short, this paper demonstrates the suitability of ultrasonic broadband signals for characterizing fiber-reinforced cementitious composites under bending stress.

Numerical simulation of the fracture behaviour of glass fibre reinforced cement

The exceptional mechanical properties that glass fibre reinforced cement (GRC) boasts are the result of the interaction of the fibres and the brittle matrix. While the cement mortar provides a remarkable compressive strength, the presence of glass fibres increases the material toughness under tensile and flexural stresses. In addition, the fracture energy is also enhanced due to the presence of the glass fibres that add a multiple cracking damage pattern and, hence, a large damaged surface. In order to provide available resources that may ease and widen the structural design of GRC, the assessment and verification of its constitutive relations is of high significance, given that such relations may reproduce the fracture behaviour. In this study, the softening function of GRC under flexural tensile fracture tests in an in-plane disposition has been obtained by combining numerical simulations with an inverse analysis. Such inverse analysis has been able to reach satisfactory results by varying the parameters that define the trilinear softening function proposed. The process started by means of an initial estimation of the values of the parameters. By iteratively modifying such values, a softening function capable of reproducing the fracture behaviour of GRC was found. The study shows that use of tri-linear softening functions reproduces with notable accuracy the fracture behaviour of three different formulations of GRC. The significance of this research lies in the provision of constitutive relations that can be used for future modelling and structural design, thus widening the feasible applications and reliability of GRC in the construction industry.