Concrete Binder Research Articles

The Military and Civilian Applications of Geopolymers

In this article, various geopolymer applications in the context of both existing and potential future military applications are summarized. Geopolymers are a type of alkaline activated concrete binder with many advantageous properties over ordinary Portland cement based materials. Geopolymers are first compared to ordinary Portland cement based materials in regards to their mechanical properties, thermal properties, chemical resistance and CO2 emissions during manufacturing. History of geopolymer applications and research is also discussed. Then, various geopolymer applications are summarized, including their use as a passive fire protection, material for general construction, “ink”for 3D printing. These types of applications are also discussed in the context of existing and potential military applications of geopolymers, including their use by U.S. armed forces and U.S. military research. Superior geopolymer resistance to explosions is also presented.

METODE PELAKSANAAN OVERLAY REKONSTRUKSI PADA PROYEK CIKOWOAN – KADUT (REGULER) DI STA 1 + 700 s/d STA 2 + 286

In terms of access to mobilization/demobilization and the location is very steep, the dump load is minimal due to poor access. Very high rainfall has resulted in further delays in the implementation of work. ACBC (Asphalt Concrete Binder Course) asphalt foundation and top layer or asphalt surface wear layer ACWC (Asphalt Wearing Course) for the material used, namely Asphalt Emulsion CSS -1 or SS -1 layer thickness (AC-BC) solid with a thickness of 0.6 cm with a loose thickness of 7.4 cm, the layer thickness (AC-WC) was solid with a thickness of 0.5 cm and a loose thickness of 6.4 cm. AC-WC compaction is divided into 3 parts, namely first compaction (breakdown rolling), second compaction (intermediate rolling), final compaction (final rolling). The first compaction is carried out when the temperature reaches 111 C to 102 C or about 0 – 10 minutes from the time the AC – WC is held. This ride uses a tandem roller with the number of tracks according to the trial compaction. The second compaction is carried out at a temperature of 102 C to 83 C or about 10-20 minutes since the AC-WC was held. This event uses a Pneumatic Roller with the number of passes according to trial compaction. The final compaction was carried out at a temperature of 83 C to 63 C or around 20-45 minutes since the AC-WC was held. This event uses a Pneumatic Tandem Roller with 12 to 15 passes. In the work of the Cikowoan – Kadut Road Improvement Reconstruction Project in Majalengka Regency, the tools used are Mini Excavators, Asphalt Tanks and assistive devices (asphalt sprayer), Dump trucks, Tandem combin rollers, Mini iron wheel compactor machines (baby roller), soil compactor machine.

Robot-Assisted Manufacturing Technology for 3D Non-Metallic Reinforcement Structures in the Construction Applications

Of all industrial sectors, the construction industry accounts for about 37% of carbon dioxide (CO2) emissions. This encompasses the complete life cycle of buildings, from the construction phase to service life to component disposal. The main source of emissions of climate-damaging greenhouse gases such as CO2, with a share of 9% of global emissions, is the production of ordinary cement as the main binder of concrete. The use of innovative approaches such as impregnated carbon yarns as non-corrosive reinforcement embedded in concrete has the potential to dramatically reduce the amount of concrete required in construction, since no excessive concrete cover is needed to protect against corrosion, as is the case with steel reinforcement. At the same time, architectural design options are expanded via this approach. This is achieved above all using novel robotic manufacturing technologies to enable no-cut direct fiber placement. This innovative technological approach to fabricating 2D and 3D biologically inspired textiles, including non-metallic structures for textile-reinforced concrete (TRC) components, will promote an automatable construction method that reduces greenhouse gas emissions. Furthermore, the impregnated yarn which is fabricated enables the production of load-adapted and gradual non-metallic reinforcement components. Novel and improved design strategies with innovative reinforcement patterns allow the full mechanical potential of TRC to be realized. The development of a robotic fabrication technology has gone beyond the state of the art to implement spatially branched, biologically inspired 3D non-metallic reinforcement structures. A combined robotic fabrication technology, based on the developed flexible 3D yarn-guiding and impregnation module and a 3D yarn fixation module, is required to implement this sophisticated approach to fabricate freely formed 3D non-metallic reinforcement structures. This paper presents an overview of the development process of the innovative technological concept.

Post-heating evaluation of fibre reinforced concrete with LC3 binder as replacement to OPC

Limestone calcined clay cement (LC3) is an emerging cement that uses reduced clinker content in production, leading to a sustainable future by reducing CO2 emissions. Compared to OPC, LC3 has performed well under normal conditions. But the residual strength of LC3 binder concrete can differ from that of OPC-based concrete at high temperatures. This experimental study highlights the effect of elevated temperature, various cooling conditions and inclusion of fibres (PPF, SF, HF) on the physical properties such as colour change, crack width, mass loss and residual compressive strength of concrete monitored using both NDT techniques and destructive testing. NDT comprised rebound hammer and UPV test carried before and after cooling heated samples. After compression testing, X-ray diffraction was used to determine the samples' microstructure and phase shift (XRD). Test results show that the compressive strength and mass loss increased significantly after exposure to 200 °C due to further hydration of un-hydrated clinkers. The performance decreased sharply after 600 °C exposure due to the decomposition of hydration products. Steel fibre had a beneficial effect, but PP fibre, due to balling, reduced concrete compressive strength. At all exposure temperatures, water quenching significantly decreases compressive strength. This reduction can be attributed to micro-crack formation caused by high thermal stress.

Effect of Micro Lime on The Ambient Cured Sugarcane Bagasse Ash-Based Geopolymer Concrete

Geopolymer concrete has been the ideal replacement for Ordinary Portland cement concrete in producing green concrete. The binder in geopolymer concrete is a cementitious paste made from amorphous Aluminosilicate and activated by an Alkaline solution. The geopolymerization process is initiated at elevated temperatures. Thus, the curing requires elevated temperatures. This curing method limits the application of geopolymer concrete in the construction industry. In a geopolymer mix, the presence of Calcium ions allows the formation of Calcium Aluminate Silicate and Calcium Silicate Hydrate gels, allowing ambient temperature curing. Therefore, this study investigates the effect of micro lime on the Sugarcane Bagasse Ash-based geopolymer concrete. The micro lime was added to the geopolymer concrete in 1, 3, 5 and 7% by the Sugarcane Bagasse Ash weight. A mix design was based on a Densified Mix Design Algorithm. The tests carried out included compressive strength and water absorption. Ambient curing of the SCBA-based geopolymer concrete was achieved with 1% of the micro lime. The compressive strength increased with the increase of the micro lime, 10N/mm2 at 1%, to 18.25N/mm2 at 7% micro lime. The ambient temperature-cured geopolymer concrete at 3% micro lime had the lowest water absorption rate.

Optimisation on the Hybridisation Ratio of Pulverised Fuel Ash and Ground Granulated Blast Furnace Slag (PFA - GGBS) for the Fabrication of Geopolymer Mortar

The current cement industry has several environmental and social problems, including high greenhouse gas emissions, air pollution, water consumption, and the generation of large quantities of waste. This matter has grown into a significant concern, and there is now a pressing requirement to substitute the conventional binding material in concrete, namely Ordinary Portland Cement (OPC). This paper presents the report on the hybridisation of two industrial by-products, namely pulverised fuel ash (PFA) and ground granulated blast furnace slag (GGBS), to produce an alternative binder known as geopolymer. A set of 11 hybrid PFA-GGBS geopolymeric mortar mixes was created using the complete range of hybridisation ratios, along with different water-to-binder ratios. The freshly mixed hybrid PFA-GGBS geopolymeric mortar was put through a flow table test to examine the required water-to-binder ratio to achieve the targeted level of workability. Afterward, all the samples were allowed to cure at room temperature before undergoing a destructive test to measure their compressive strength. According to the study's findings, the highest compressive strength of 4.6 MPa was achieved with a PFA-GGBS hybridisation ratio of 60-40 in the geopolymeric mortar. However, when the content of GGBS exceeded 40 %, the compressive strength of the hybrid PFA-GGBS geopolymeric mortar produced tended to decrease. Additionally, as the replacement level of GGBS increased, the required water-to-binder ratio also increased to maintain the targeted level of workability, ranging between 0.31-0.41. The PFA-GGBS hybridisation ratios of 60/40, 50/50, 40/60, and 30/70 have shown promising properties to be further refined regarding their application in cementless concrete. Moreover, the study conducted to replace cement as a binder in concrete has the potential to make the construction industry more sustainable and reduce carbon emissions by utilising industrial waste ash that would need to be affordable, strong, durable, and widely available in order to be practical.

High-Strength Building Material Based on a Glass Concrete Binder Obtained by Mechanical Activation

As part of the work, the chemical interaction of finely ground glass (~1 μm), calcium oxide, and water was studied. It is shown that an increase in the fineness of grinding makes it possible to abandon autoclave hardening in the production of products on a hydrosilicate binder. The study of chemical interaction was carried out by calculating the thermodynamic equilibrium and was also confirmed by XRD analysis. DTA analysis showed that an increase in the treatment temperature leads to an increase in the proportion of the reacted phase at the first stage. Subsequently, phase formation is associated with the presence of CaO. The carrier of strength characteristics is the CaO×2SiO2×2H2O phase. The selection and optimization of the composition make it possible to obtain a high-strength glass concrete material with a strength of about 110 MPa. The micrographs of the obtained samples correspond to classical hydrosilicate systems.

Effect of ambient curing periods on the mechanical properties of geopolymer concrete prepared with three mineral admixtures and glass fibers

Fly ash serves as the primary binder in geopolymer concrete (GPC), Several experiments have been performed using ground blast furnace slag (GGBS) as a fly ash additive in GPC and the results show that GGBS enrichment improves the mechanical properties. Existing experimental investigation employs a constant (optimum) percentage of condensed silica fume (CSF) along with GGBS as part replacement of fly ash in GPC of M40 grade. Glass fiber reinforcement was incorporated at percentages of 0.5,0.75 and 1.0 in the GPC composite. Laboratory specimens were prepared, and the mechanical properties were found at various curing periods ranging from 7 days to 60 days under ambient conditions. It is inferred that extended curing periods at ambient conditions have increased the mechanical strengths of GPC mixes. Glass fiber has contributed to strength increase, particularly in tension and flexure. Condensed silica fume has contributed towards more strength and workability of GPC.

Structural and mechanical studies of a ground-granulated blast-furnace slag (GGBS) based binder and its use in earth concrete

The aim of this work is to characterize the mechanical properties with the understanding of the chemical reactions of a ground granulated blast-furnace slag (GGBS) based binder for earth concrete. Both binder paste and earth concrete samples are cured at 20 °C and 100% of relative humidity. Several characterization techniques are conducted, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (ATR-FTIR) and mechanical tests. The compressive tests are done at 7, 28 and 90 curing days. This study shows that dicalcium silicates found in the binder powder leads to calcium silicate hydrates (C-S-H) formation in the early age. It also reveals the presence of portlandite, leading to the calcium-activation of the GGBS. This latent reaction creates several phases such as C-S-H and C-A-H in the mid and long term. The analyzis of the infrared specters corroborates those results. The C-S-H characteristic bands are identified around 400, 655 and 960 cm-1. C-A-H characteristic peak is identified at 850 cm−1. The mechanical study shows that the compressive strength of the binder reaches 13.9±0.3 MPa, 21.1±0.8 MPa and 25.4±0.7 MPa and the earth concrete 8.9±0.7 MPa, 16.6±0.3 MPa and 18.7±0.2 MPa at 7, 28 and 90 curing days respectively. Those mechanical properties are brought by the hydrates formed during the binder’s reaction. It creates a matrix that bounds the grains of raw earth together. This work highlights the high mechanical properties of earth concrete made out of this binder. It also shows the potential of calcium-activated GGBS and pozzolanic reactions in order to create low carbon earth concrete with good resistance. Such binder may foster the use of earth concrete in buildings, enhancing their thermal comfort and energy efficiency while reducing their environmental impact.

Asphalt concrete mix analysis using volcanic ash filler

Asphalt mixture is a combination of a mixture of aggregate and asphalt. Sinabung eruption volcanic ash produced many negative impact on health and the environment. So that needs to be done in order to study the volcanic ash can be used in road pavement, especially on Asphalt Concrete pavement, the purpose of this study to determine the effect comparison of volcanic ash filler sinabung on Asphalt Concrete - Binder Course. This research was laboratory experimental in nature with asphalt level variation of 5%, 5.5%, 6%, 6.5%, 7% and volcanic filler level of 1, 2 and 3% in each asphalt level variation. There were 5 samples used the examination was done using marshall test instrument. The test used to determine the graph of asphalt content with value stability, flow, bulk density, VIM, VMA, VFB. The results of the over all addition of volcanic ash in the petroleum asphalt. Asphalt Concrete Binder Course Marshall stability values indicate that the better that showed that a mixture of aggregate is very good. If the flow value is lower, the VIM value is getting lower, then the VMA value and VFB value have a value that is more than the minimum value.

Experimental study to reduce the emission of carbon dioxide from cement plants: a case study on Asiabar local mineral pozzolan

This study aims to optimize the local mineral pozzolan (Asiabar) weight fraction in concrete mixture. Four concrete mixtures by replacing the cement with 5, 10, 15, and 20% of pozzolan by weight were considered. The compressive, X-ray Diffraction Analysis (XRD), and Scanning Electron Microscopy (SEM) tests have been used to examine the mechanical properties, microstructural analysis, and morphology of proposed concrete mixtures to evaluate the impact of using local mineral pozzolan. According to the results, the best replacement ratio of this pozzolan in the concrete is equal to 15% by weight of the cement, which enhances the strength by 24% compared to the ordinary cement concrete. The chemical reaction of pozzolan in the concrete binder reduced the content of portlandite and calcite. This pozzolan also decreased the number of pores and enhanced the integrity of the interfacial transition zone (ITZ) in the concrete compared to ordinary (Portland) cement concrete. Also, this pozzolan emits less CO2, 15.20 kg/m3, than ordinary cement concrete. Due to the effects of this pozzolan in Structural strengthening and reducing cement consumption in concrete, the study may introduce Asiabar mineral pozzolan as an environmentally friendly cement replacing agent with the potential to enhance the strength of concrete.

Reusing thermoactivated construction waste spoil as sustainable binder for durable concrete: Microstructure and chloride transport

Construction and demolition waste is predominantly comprised of construction spoil. However, the proper recycling of this construction spoil in a manner that maximizes its value has historically received insufficient attention. Therefore, the objective of this study investigated the micro-structure and chloride transport of cement concrete including thermoactivated construction spoil powder (CSP) as a substitute for cement. The results highlights that the un-treated CSP consisted of massive inert components, and active metakaolin and amorphous components were generated in thermoactivated CSP after 800–1200 ℃ activation treatment. Mixing un-treated CSP negatively impacted the micro-structure and strength development of concrete, but the thermoactivated CSP blended paste had improved micro-structure and better strength than the un-treated CSP blended paste. Incorporating un-treated CSP raised the chloride transport in concrete. At the constant replacement ratio of CSP, the thermoactivated CSP blended concrete had lower chloride transport than the un-treated CSP blended concrete, and decreasing the particle size of thermoactivated CSP could further decline the chloride transport in thermoactivated CSP blended concrete. The concrete with 1200 ℃-activated CSP even had lower chloride transport than the reference concrete. The mix of un-treated CSP up to 30% reduced the chloride binding capacity of concrete, but the thermoactivated CSP blended concrete had superior chloride binding capacity to the un-treated CSP blended concrete. Particularly, the concrete with 20% thermoactivated CSP and 10% active metakaolin/silica fume had similar strength and lower chloride transport than reference concrete. By optimizing the thermoactivation temperature, replacement ratio, and particle size of CSP, it was possible to prepare a durable concrete with low chloride transport.

Investigation of Durability Properties for Lightweight Structural Concrete with Hemp Shives Instead of Aggregate

The paper presents the results of testing the performance of lightweight structural concrete containing hemp shives as an aggregate. It has been analysed how the higher binder content and use of the Portland cement affect the thermal and microbiological properties of the lightweight concrete. The aggregates of the plant origin and cement are incompatible because the plant chemical compounds, dissolved in water or an alkaline environment, inhibit cement hydration. To avoid this, mineralisation of the aggregates of plant origin is necessary. The most often used binder in hemp concrete is hydrated lime, a mineraliser. An addition of hydrated lime and sodium trisilicate was used for hemp shiv mineralisation in the tested materials with a cement binder. Concrete containing hemp shiv and cement binder, of which volume share in the concrete was at most 15%, was prepared as a reference concrete. In the remaining three concretes, the total content of the binder in relation to hemp shiv (by mass) was increased 2.5 times. It was shown that lime-binder hemp concrete offers a promising antimicrobial strategy, as it can inhibit bacterial and fungal growth on their surface with superior efficacy. The best results were obtained for tested concretes with the cement–lime binder regarding compressive strength; the average compressive strength was 9.56 MPa.

Characteristics the Marshall Test Subsitutution of Polypropylene Plastic Pellets as Filler in Mixture Asphalt Concrete Binder Course (AC BC)

This research was carried out on a laboratory experimental scale, with the aim of determining the characteristics of the Marshall test for the substitution of Polypropylene plastic pellets in the Asphalt Concrete Binder Course (AC BC) mixture. The substitution of Polypropylene plastic pellets in AC BC mixture is 1%, 2%, 3% of the weight of filler in AC BC standard mixture. From the test results, it can be concluded that the characteristics of the marshall test include VMA values, VIM values, VFA values, stability values, flow values, MQ values that meet the predetermined requirements both without filler and with filler.

Performance evaluation of bamboo leaf ash and steel slag powder as alternative filler in asphaltic mixes

The need to improve the quality of asphalt concrete and to control the disposal of waste into the environment has been an issue of concern to most researchers. This study investigated the re-use of bamboo leaf ash (BLA) and steel slag powder (SSP) as replacements for conventional mineral filler, quarry dust (QD). Asphaltic concrete binder (BC) and wearing (WC) courses were prepared with SSP and BLA, while QD was used as control. Laboratory tests were carried out on the BC and WC to determine the Marshal and mechanical properties of the mixes. The properties are stability, flow voids, indirect tensile strength, tensile strength ratio, fatigue test, resilient modulus, cantabro loss test, skid resistance, and retain strength. The performance of asphalt mixtures containing SSP improved the marshal stability, indirect tensile test, ravelling resistance, and rutting resistance of the asphaltic concrete by 10, 15, 20, and 25%, respectively, more than the control compared to BLA. The moisture resistance, fatigue, and resilience moduli of the control (QD) were found to be a little higher than the SSP and BLA, with 15, 20, and 25%, respectively. The use of BLA and SSP is cheaper as compared to conventional fillers; BLA and SSP for wearing and binder courses are 4.35%, 4.13%, and 3.17%, 3.03% lower respectively, for 1 tonne of asphalt concrete produced. The result of this study suggests that re-using SSP and BLA can be a substitute for conventional filler to achieve a more satisfactory performance, cost-effectiveness, and a means of effective waste disposal.

Robust clay binder for earth-based concrete

The use of excavated earth is a circular and carbon neutral solution gaining growing interest. However, its high variability in properties makes it difficult to master as raw materials for construction. The objective of this paper is to highlight the key parameters allowing overcoming the influence of the variability of soil composition on the earth-based concrete properties. We show that the solid volume fraction of clay paste is the key parameter allowing predicting the fresh state properties of the clay binder, whatever the constitutive clay type, whereas the clay activity and the dry density of the material control the compressive strength of the material. These promising results, validated on sludge, pave the way to optimized mix design strategies for robust earth concrete products.

Optimised processes for the production of performance concrete constituents based on agricultural wastes

In most parts of the world urban populations are growing. This inevitably requires resources for construction materials, which is a challenge to achieving global climate goals. Since there is no alternative to concrete as structural material, novel approaches are required to use cement in concrete more efficiently and to use as little Portland cement clinker in the binder for concrete. With novel approaches, Africa can spearhead green urban construction technologies globally, as the continent’s carbon emissions re marginal today in comparison to the rest of the world and the potential to use local resources are enormous. The authors of the paper develop conclusions on how bio-waste can be converted to organic and mineral concrete constituents that have a potential to create rural livelihoods and urban construction materials markets. A three-step solution including a hydrothermal process, a pyrolysis step and a co-fuelling process with brick production in a vertical shaft kiln is suggested to derive organic components, various by-products as well as bricks and pozzolanic cement replacements, respectively.

Sustainable Consideration of Concrete using GGBFS and Fly Ash

Abstract: The economy of the nation is significantly influenced by the construction industries. The most common material used in construction is concrete. The fundamental components of concrete are cement, sand, aggregate, and water. Cement is the primary binder in concrete. 10% to 15% of the total volume of concrete is made up of cement. Large amounts of CO2 gas are released during cement production, which is very harmful to the environment. According to several studies conducted, waste products or by-products such as Fly Ash, GGBFS, silica fume, metakaolin, etc., can be employed as a cement substitute. In this study, the experimental evaluation of the compressive strength of concrete for M25 grade concrete using partial cement replacement with 10%, 15%, 20%, and 25% of GGBFS and Fly Ash is presented. For all blends, a W/C ratio of 0.5 is used. When the concrete has been cast and given a 7 and 28 day curing period, testing has been conducted. The possibility of using waste material in structural cones is the main topic of this study. Reduced cement use will result in less CO2 being produced, which will help to preserve the environment and be cost-effective. The use of industrial waste has evolved as aggressive construction material, thus feature as Sustainable construction.

Performance of Geopolymer Concrete with Combined Use of Sodium Hydroxide and Potassium Hydroxide

From the beginning, binders such as red mud mortar, lime mortar, cement mortar, etc., played a major role. It has been found that the production of cement increases the quantity of uncontrollable CO2 emissions. Another adhesive that can be used in place of cement is geopolymer. Because geopolymer concrete may reduce carbon emissions, the concrete business could grow sustainably and prosper as a result. This technology has the potential to reduce CO2 emissions from the construction sector by up to 80%. To make the binder for geo polymer concrete, alkaline solutions are used to activate sources of materials rich in silica (Si) and aluminium (Al), such as fly ash, GGBS, etc. Geopolymer-made concrete includes no cement at all. In this study, we attempted to determine the compressive strength and durability properties of geopolymer concrete using various molarities of 8M, 10M, and 12M along with Sodium Silicate solution. The alkaline activators used were Sodium hydroxide (NaOH), Potassium hydroxide (KOH), and combination of both (50%NaOH + 50%KOH). To achieve the highest pH value for better mechanical and durability characteristics, chemical analysis is done. After 7 and 28 days of age, the Compression and Permeability experiments were conducted. The GPC's strength and durability characteristics were contrasted with those of conventional concrete.

Waste Clay Brick as a Part Binder for Pavement Grade Geopolymer Concrete

AbstractGeopolymer concrete (GPC) was developed using one-part binders made from a mixture of waste clay brick (WCB) powder, fly ash, and slag in the precursor. Its suitability for use in rigid pavement construction was evaluated based on fresh properties, hardened properties, and durability characteristics. The effects of sealed and unsealed ambient curing and the size of the WCB particles on the strength of the GPC were also examined. Sealed ambient curing significantly increased the strength of the GPC, with longer sealing periods resulting in even stronger concrete. Sealing prevented water loss from the samples and reduced carbonation, protecting the concrete from microcracks caused by dehydration. The GPC created in this study met the basic strength requirements for use in rigid pavement applications, with 28-day compressive strengths above 40 MPa and flexural strengths above 4.5 MPa. All GPC samples had a water absorption of more than 5%, with a maximum of 7.4%. The apparent volume of permeable voids was less than 14%, which is the maximum allowable value for a 40 MPa pavement-grade concrete. The GPC was resistant to abrasion and cyclic wetting and drying, and experienced only a slight reduction in compressive strength after being subjected to these cycles. There were no significant differences in the wearing depth of the top and bottom surfaces of the slabs, indicating better compaction and homogeneity of the mix.