Self-compacting Mortar Research Articles

Evaluating the high‐temperature resistance of self‐compacting mortar incorporating waste andesite powder as a mineral admixture

AbstractSignificant amounts of waste material are generated at various stages of andesite stone processing, including mining, cutting, and polishing. Despite this, limited research has been conducted on the potential use of waste andesite powder (WAP) as a mineral admixture. The impact of WAP on the high‐temperature resistance of cement‐based composites remains largely unexplored. This study aims to evaluate the benefits of incorporating WAP as a partial substitute for Portland cement. Self‐compacting mortars (SCMs) with varying WAP replacement rates (5%–30%) were produced and subjected to temperatures of 300°C, 600°C, and 900°C. Additionally, ternary mixtures of WAP and silica fume were produced for comparative analysis. The results showed that SCMs containing up to 10% WAP exhibited higher 90‐day compressive strength compared to the control sample. Furthermore, WAP inclusion improved high‐temperature resistance, and the use of WAP at higher replacement rates was feasible when combined with mineral admixtures possessing high pozzolanic activity, such as silica fume.

Improvement of properties of high volume fly ash based self-compacting mortar with dolomite and ground granulated blast furnace slag

Usage of filler with inert or pozzolanic property has been crucially required for fabricating the practicalself-compacting mortar or self-compacting concrete. The current study investigates the influence of usingthe dolomite powder on the enhanced properties of the high volume Class F fly ash self-compacting mortarwith/without addition of ground granulated blast furnace slag (GGBFS/slag). Experimental results showed thatpartial replacement of low calcium Class F fly ash with the dolomite powder not only increased the workability of the fresh modified self-compacting mortars but also enhanced the ordinary Portland cement hydrationprocess at early. The adjustment of dolomite powder addition as partial replacement of fly ash resulted in themodified self-compacting mortars with the compressive strength increased after 7 days of curing. 30 masspercent of dolomite powder partially replacing fly ash was considered as the optimum value to induce the hardened modified self-compacting mortars with the compressive strengths increased at 4.2, 10.4, and 10.5% at3, 7, and 28 days, respectively. With the content of dolomite powder being fixed at 30 and 50 mass percent,partial replacement of fly ash with slag at 50 mass percent induced the modified self-compacting mortars withsignificant enhancement of the engineering properties.

Use of Milled Acanthocardia tuberculate Seashell as Fine Aggregate in Self-Compacting Mortars.

This study focuses on the feasibility of using ground Acanthocardia tuberculate seashells as fine aggregates for self-compacting mortar production. The obtained results show a promising future for coastal industries as their use eliminates waste products and improves the durability of these materials. The use of Acanthocardia tuberculate recycled aggregate, in terms of durability, improves the performance of all mixes made with seashells compared to those made with natural sand, although it decreases workability and slightly reduces mechanical strength. Proper mix design has beneficial effects, as it improves compressive strength, especially when the powder/sand ratio is 0.7. Three replacement ratios based on the volume (0%, 50%, and 100%) of natural limestone sand with recycled fine aggregate from Acanthocardia tuberculate seashells, and three different dosages modifying the powder/sand ratio (0.6, 0.7, and 0.8), were tested. The fresh-state properties of each self-compacting mixture were evaluated based on workability. The mineralogical phases of the hardened mixtures were characterised using X-ray diffraction, thermogravimetry, and differential analyses. Subsequently, the mechanical and durability properties were evaluated based on the compressive and flexural strengths, dry bulk density, accessible porosity for water and water absorption, drying shrinkage, mercury intrusion porosimetry, and water absorption by capillarity. Therefore, the use of Acanthocardia tuberculate seashells in cement-based systems contributes to circular economy.

Mechanical Properties of Self-Compacting Mortars Containing Rubber Waste Particles as Fine Aggregate in Freeze–Thaw Cycles

Mechanical Properties of Self-Compacting Mortars Containing Rubber Waste Particles as Fine Aggregate in Freeze–Thaw Cycles

Effect of Ground Diatomite on Early Strength of Self-Compacting Mortars

Portland cement fabrication is a significant factor that increases the amount of carbon dioxide released into nature. For this reason, it is very important to use natural and waste materials with pozzolanic properties instead of portland cement. In this article, the usability of diatomite rock, a natural pozzolanic material that can be substituted with portland cement, in the manufacture of self-compacting mortar was studied. In the experimental study, prismatic specimens with dimensions of 40 × 40 × 160 mm were used to examine the impact of ground diatomite on the early age mechanical properties of self-compacting mortar; it was produced by replacing 0%, 5%, 10%, 15%, 20% of diatomite with portland cement, respectively. The slump-flow test to obtain self-compacting mortar was conducted according to the European Federation of Specialized Construction Chemicals and Concrete Systems guidance. Specimens prepared using 0%, 5%, 10%, 15% and 20% diatomite were cured in water at 23±2 ̊C temperature for 3 days. 3-day (early age) flexural and compressive strength worths were gained for the samples whose curing period was completed. As a result of this experimental study, it was specified that the highest strengths were in the series containing 5% diatomite, exceeding the reference samples. Additionally, it has been determined that mechanical strength decreases when the diatomite ratio in mixtures is more than 5%.

The Effects of Dolomite Powder Content and Type on the Yield Stress Relationship between Self-Compacting Mortar and Paste

The Effects of Dolomite Powder Content and Type on the Yield Stress Relationship between Self-Compacting Mortar and Paste

Enhancing the performances of self-consolidating composite mortars with Alfa fibers and slag: A combined Taguchi-ANN optimization

Alfa fiber-reinforced self-compacting mortars (SCMs) offer enhanced workability. Thus, the potential of combining natural Alfa fibers and ground granulated blast furnace slag (GBFS) to optimize the rheological and mechanical properties was ascertained. The effect of fibers and GBFS on the properties of SCMs after treatment with linseed oil and NaOH was also evaluated. Partial substitution of cement by slag (10 % and 30 %.) was achieved. Mini cone spreading, V-funnel flow tests as well as compressive and bending tests at 7 days and 28 days were performed on the prepared mixtures. For optimization and predictive purposes, both Taguchi optimization and Artificial Neural Network modeling were employed. Our results indicated that, according to Taguchi experimental design, the use of 1 % fiber in the initial mixture achieved a good distribution within the paste and improved flexural strength. In addition, the treatment of fibers with NaOH actually improved the structure and bonding surface. Fiber content and GBFS replacements achieved the desired rheological and mechanical characteristics. Prediction of both compressive and flexural strengths was successfully achieved by an accurate application of machine a learning algorithm based on six inputs, one hidden layer and four outputs. The combined ANN-Taguchi approach provided accurate predictions of SCM performances and identified a robust mix-design that was less prone to fluctuations in the initial material properties. Alfa fibers and GBFS promoted both fresh and hardened properties. This study demonstrated the effectiveness ML and statistical optimization in developing high-performance, sustainable-SCMs with superior workability and strengths, making them ideal for various construction applications.

Investigation of mechanical, durability, and thermal properties of sustainable self-compacting mortars containing construction demolition waste and supplementary cementitious materials

This study aims to produce sustainable self-compacting mortar (SSCM) to provide solutions to the waste generation caused by the construction industry and to provide alternative solutions to the increasing consumption of natural resources and cement. In SSCM designed as 12 different mixtures; recycled sand (RCS) and pumice were used as aggregate and silica fume (SF) and fly ash (FA) were used as supplementary cementitious materials (SCM). The mechanical, durability, and thermal properties of the produced SSCM were investigated. Compressive and flexural strengths were determined at age of 7, 28 and 90 days. Significant increases in flexural and compressive strengths were observed for 10 % SF and 10 % FA substitutions. After 90 days of water curing, the specimens were exposed to high temperature. A decrease of up to 93.4 % in flexural strength was observed after high temperature effect. Sorptivity, water absorption and porosity values were determined. Thermal conductivity test was also performed on the specimens. Significant changes were observed due to the use of SCM. The global warming potential (GWP), and energy consumption (EC) were considered to evaluate environmental properties. Significant reductions in GWP and EC values were observed for mortar series with 30 % SCM. Significant gains were achieved in economic properties due to the use of SCM, with total costs decreasing by approximately 10 %, especially in series with 30 % SCM. SSCM produced using recycled aggregates and SCMs have provided significant contributions to sustainability.

Effect of para-wood ash and calcium carbonate on the properties of eco-friendly self-compacting mortar reinforced with electronic waste fibers

This paper deals with reducing CO2 emissions from cement production and finding alternative uses for electronic waste (E-waste) fibers in some innovative applications in self-compacting mortar (SCM). In the present research, an attempt has been made to establish the optimum incorporation of E-waste fiber into SCM by varying the fiber content from 5 % to 25 %, combined with para-wood ash and calcium carbonate as supplementary cementitious materials. In this laboratory study, the mix design had a constant water-to-powder ratio of 0.35 and a cement content of 550 kg/m³. Additionally, 20 % of the cement volume was replaced by 10 % para-wood ash and 10 % calcium carbonate. The results indicated a continuous increase of the mini-slump values from 255 mm for the control mix to 270 mm for the mix with the highest fiber content. Mini V-funnel flow times increased from 3.63 to 8.83 s as the fiber content increased. Lower fiber contents of 5 % improved compressive strength because they had a reinforcing role in the matrix of SCM besides the microcrack-bridging role. Higher contents of 10–25 % decreased the strength due to the clustering of fibers and resulting voids. SEM analysis at 28 days showed increased voids with higher percentages of E-waste fibers and para-wood ash alone. The results underline that optimizing fiber content is critical in balancing workability and mechanical properties, and 5 % e-waste fiber content can be considered optimal for enhancing the performance of SCM. This work also creates part of sustainable construction practice with the green solution required to reduce CO2 emissions and work accumulation against E-waste.

Effect of curing conditions on cement based self-compacting mortar produced with mortar waste aggregate

Concrete and mortar wastes, which have a large volume and economic value among construction demolition wastes, are the most targeted demolition waste group to be recycled. An important area where construction demolition waste can be utilized is self-compacting mortar (SCM) systems. SCMs are innovative and economical systems designed to minimize the labor requirements that are difficult to meet in the production process. In this study, mortar waste aggregate (MWA) obtained by mechanical crushing and grinding was used in SCM elements by substituting different ratios (5-10-20-30-40 %) by mass to aggregate. In this way, it was aimed to evaluate both the sustainability of MWAs and the usability of MWAs in SCMs, which are considered as a new production technology. The fresh and hardened mortar tests performed in the study are presented comparatively. The physical (dry unit volume weight, porosity), durability (capillary water absorption) and mechanical properties (flexural tensile, compressive strength) of the hardened SCM elements are based on the determinations made at 3, 7 and 28 test days and according to different curing conditions (water curing, air curing and heat curing).In addition, X-ray Diffractometer (XRD) analysis was performed on specimens obtained from 0 %, 10 %, 20 % and 40 % MWA substituted specimens after heat curing (after 7 days water curing) and 28 days water curing. In the light of the data obtained, it is reported that SCM production with 10 % MWA substitution is feasible in terms of sustainability and engineering properties evaluated in this study.

Durability self-compacting mortar under external chemical attacks based on composite binder

Durability self-compacting mortar under external chemical attacks based on composite binder

Mechanical properties and durability evaluation of self-compacting mortars containing glass and brick powders

Mechanical properties and durability evaluation of self-compacting mortars containing glass and brick powders

The Multifaceted Comparison of Effects of Immobilisation of Waste Imperial Smelting Furnace (ISF) Slag in Calcium Sulfoaluminates (CSA) and a Geopolymer Binder.

Using waste materials as replacements for sand in building materials helps reduce waste and improve the properties and sustainability of the construction materials. Authors proved the possibility of using imperial smelting furnace (ISF) slag granules as a 100% substitute for natural sand in self-compacting (SCC) cement-based mortars of calcium sulfoaluminates (CSA). The study proved that ISF slag's radioactive properties meet this area's requirements. CSA cement eliminates the noted problem in the case of concrete with Portland cement, which is the extended setting of the cement binder. The research findings indicate that using slag to replace sand up to 100% in mortars without grains smaller than 0.125 mm allows high flowability, compaction, low porosity and mechanical parameters. The compressive strength of the CSA cement mortars was about 110 MPa, and more than 140 MPa for geopolymer mortar. Unfortunately, the alkaline pH of a geopolymer causes high leachability of barium and sodium. Thus, the CSA cement is in a more favourable binder to achieve high strength, is environmentally friendly, and is a self-compacting mortar or concrete.

The effect of slag and natural pozzolan on the rheological and compressive strength properties of recycled self-compacting mortar

Cement replacement materials are used in self-compacting concrete mixes to reduce the cement content and hence its environmental effect. This article examined the effects of ground granulated blast-furnace slag (S) and natural pozzolan (NP) powder on the rheological and mechanical properties of recycled self-compacting mortar (RSCM). Natural sand was replaced by 100% of recycled sand (RS) by volume; while cement was replaced by slag and NP up to 40% by weight of cement. The slump flow, V-funnel time, yield stress and plastic viscosity and compressive strength of RSCM are investigated and compared with natural self-compacting mortar. The results showed that fresh properties of RSCM meet the requirements of self-compacting mortar if slag and NP contents are limited to 35%. The increase in slag content increases the yield stress and the plastic viscosity of fresh mortars whereas a decrease in the rheological properties is noticed when NP content is increased. Increasing slag and NP content leads to a reduction in compressive strength of RSCM at early ages, but enhances compressive strength at later age. The cement substitution levels by 25% of slag and 15% of NP are the optimum for attaining the desired strength that compensate for strength loss due to the use of RS.

Experimental and Numerical Study on Compressive Behaviour of Circular Reinforced-Concrete Column with Pre-fabricated Self-compacting Mortar Stay-in-Place Formwork Strengthened with CFRP Layers

Experimental and Numerical Study on Compressive Behaviour of Circular Reinforced-Concrete Column with Pre-fabricated Self-compacting Mortar Stay-in-Place Formwork Strengthened with CFRP Layers

Mechanical and durability performance of self-compacting mortars made with different industrial by-products as fillers

This study evaluated the performance over time of Self-Compacting Mortars (SC mortars) with different industrial by-products simultaneously; Electric Arc Furnace Dust (EAFD) and fly ash, conforming (FA) or not conforming (NcFA), from coal-fired power plant or recovery filler from hot-mix asphalt plant (RF). Different SC mortars mixes were produced; three mixes with different EAFD ratio incorporation (0 %, 10 %and 20 %) for each the other industrial by-products (FA, NcFA and RF) substituted of cement at 30 %; and additional three mixes with 60 % of cement replacement by FA and the same EAFD incorporation ratios. To study the performance over time of these SC mortars, tests such as electrical resistivity, ultrasonic pulse velocity, drying shrinkage, capillarity, compressive and flexural strength were carried out up to 91 days of curing. The SC mortar compositions was evaluated by TGA/DTA and DRX analysis. Previously, the by-products used were characterized. The EAFD incorporation showed a strong influence in SC mortars, independently of the industrial by-product used. The initial inhibition of development of hardening in SC mortars due to the presence of ZnO in EAFD was lifted over time up to some extent. The simultaneous use of different industrial-by products in SC mortars in high volume content walks towards the sustainability in the construction sector.

Cross-sectional shape effect of stay-in-place formwork column on axial compressive behaviour

Experimental and numerical studies on the behavior of composite columns with prefabricated self-compacting mortar (SCM) stay-in-place (SIP) formwork and post-cast normal-strength core concrete were presented.The axial compression of twenty-eight reinforcement concrete (RC) composite columns having square or circular cross-section shapes, with formwork thicknesses of 10 mm or 15 mm, and confined with one or two layers of Carbon Fibre Reinforced Polymer (CFRP (, were tested. A finite element (FE) model was generated to simulate the stress–strain relationship, and failure mode of the column using ABAQUS software. The results show that square cross-section-shaped columns exhibited lower axial load and displacement capacities than their counterparts of equivalent circular cross-section-shaped columns. This behavior maintained consistent regardless of the use of the SCM-SIP formworks or the wrapping with CFRP fabrics. Among the various confinement systems compared in this study, the efficiency of the CFRP was the greatest. Good bonding with no peeling failure was observed between SCM-SIP formwork and core concrete, indicating the good integrity of the composite columns. Consistency between the FE model and experimental results was observed for both cross-section shapes, indicating the precise and plausible characteristics of the model to sensibly estimate the stress-strain behaviors.

Use of sludge from water treatment decanter in cement composites

The objective of this manuscript is to present a sustainable alternative for the use of waste from Water Treatment Plants (WTPs), specifically water treatment sludge (WCS), in civil construction. The proposal is to use water treatment sludge as a construction material, more specifically in the partial replacement of cement in self-compacting mortars (SCC). Due to the significant use of natural resources in civil construction and the consequent environmental degradation, the use of water treatment sludge (WCS) as a construction material may be an option. However, the low quality of river water and the need for drinking water force water treatment plants to use greater quantities of chemical compounds, resulting in a significant waste known as WCS. The methodology used for dosing self-compacting concrete (SCC) follows the process described by the Gomes method, which is applicable to both concrete and self-compacting mortars. In this study, the partial replacement of cement at 2.5% and 10% with water clarification mud (WCS) in self-compacting mortars (SCC) was analyzed and it was found that the compressive strength increased from 27.3% to 30% for the specimens, with the addition of 2.5% and 10% of WCS, respectively. A life cycle assessment was carried out to prove the environmental benefits of replacing cement with WCS. The results preserve the feasibility of applying WCS in civil construction while at the same time highlighting the need for additional research on the topic.

Wood Ash Effect on Cement Based Self-Compacting Mortars

In this experimental study, the effect of wood ash (WA) substituted into Portland cement (PC) at variable proportions by volume on the fresh state, hardened state, and microstructure of self-compacting mortars (SCMs) was investigated. In the designed SCMs, WA was substituted into PC at 5% increasing ratios in the 0%-30% band. A total of 84 40*40*160 mm prism specimens and 42 50*50*50 mm cube specimens were produced for 7 different SCM designs. V-funnel and slup flow test were done according to EFNARC kriteria. Hardened state tests were carried out at 7, 28, 56 and 90 days with oven dry unit volume weight, porosity, capillary water absorption, flexural tensile, compression and splitting tensile tests. In addition, WA used in the mixture and after 28 days of water curing, samples containing WA 0%, 15%, 30% were evaluated after microstructure analysis. According to the results of the study, increasing WA substitution rate has a determining effect on the fresh state properties. Increasing WA substitution has a negative effect on flexural tensile strength and compressive strength and a variable effect on splitting tensile strength. Increasing the amount of WA increases the unit volume weight and decreases the porosity at 5% substitution. For the other substitution cases, the unit volume weight decreases and porosity increases. Except for the control mixture, Magnesium calcite and Aluminum-based compounds were detected in microstructure examinations of SCMs.

Effect of four-component binder on characteristics of self-compacting and fibre-reinforced self-compacting mortars

AbstractThe hydration heat of a four-component binder consisting of Portland cement (CEM I 42.5 R), blast-furnace slag (BFS), metakaolin (MK), and silica fume (SF) was investigated using a conduction calorimeter and thermal analytical method to optimize the material composition of self-compacting mortar (SCM). Then, the influence of material composition with different substitution levels (0, 25, 30, and 35% labelled as SCM100, SCM75, SCM70, and SCM65) on physical and mechanical properties of the mortars with two volumetric binder sand ratios of 1:1 and 1:2 (cement: sand) was evaluated. Furthermore, two mortar compositions comprising SCM75 and sand at 1:1 and 1:2 ratios were used to prepare fibre-reinforced self-compacting mortars in five combinations (0, 0.25, 0.5, 0.75, and 1%) of two fibres (polypropylene-PPF and basalt-BF) at a constant content of 1.00 vol%. The properties of the prepared samples were investigated with respect to the characteristics of self-compactibility and mechanical properties of fresh and hardened states, respectively. The rheology characteristics expressed by slump flow, V-funnel, and T20 were found following the EFNARC guidance. The partial replacement of cement by supplementary cementitious materials has enhanced the performances (compressive and flexural strengths, dynamic modulus of elasticity) of self-compacting mortars from the 7th day through pozzolanic activity. Furthermore, adding fibres has enhanced the DME and microstructure of the self-compacting mortars.