Final Water Absorption Research Articles

Biopolymer-assisted stable halloysite nanotubes dispersion in alkaline environment and their application in cementitious composite

The colloidal dispersion of biopolymer-treated HNTs in the cementitious environment was studied. Three different biopolymer treatments, namely casein (C), guar gum (GG), and xanthan gum (XG), were utilized to prepare the stable colloidal dispersions of HNTs in such environments. The examination of the dispersion and time-dependent stability of untreated HNTs in a synthetic pore solution (SPS) revealed rapid agglomeration and settling of the particles. Specifically, the stabilization of XG-treated HNTs was superior compared to those treated with GG and C biopolymers. XG-treated HNT suspension in the pH 13 environment existed as monodisperse nanoparticles centered around 20 nm, while bare HNTs existed as polydisperse across 200 nm to 7000 nm. Moreover, XG-treated HNTs boosted cement mortar samples, increasing compressive strength by 29.4 % and reducing initial and final water absorption by 15.8 % and 19.9 %, respectively, after 90 days. Furthermore, the microstructural morphology of the HNT-XG-modified mortar exhibited improved compactness and homogeneity.

Mechanical Properties of Fiber-Reinforced High-Volume Fly-Ash-Based Cement Composite—A Long-Term Study

This article presents the long-term mechanical properties of a novel cement composite, no-aggregate concrete (NAC), containing 80% of low-calcium (class F) fly ash (F-FA) and 20% ordinary Portland cement (OPC) without aggregates. The study investigates the effect of adding polypropylene fibers (PPFs) in varying volume fractions to NAC by conducting compressive, splitting tensile, flexural, bond strength, and sorptivity tests, emphasizing the morphological features over a curing duration of up to three years. The results indicate that adding PPF has an insignificant effect on compressive strength. However, flexural, splitting tensile, and bond strength improve with an increasing volume fraction of PPF. The addition of PPF achieves a ductile failure which is desirable. The initial and final water absorption rate (sorptivity) reduces with the addition of PPF. Further, scanning electron microscopy (SEM) images reveal dense precipitation of C-S-H, while energy-dispersive X-ray spectroscopy (EDS) quantifies the hydration products. The ultrasonic pulse velocity (UPV) affirms the composite’s excellent quality.

Experimental Study on Mechanical Properties and Durability of Polymer Silica Fume Concrete with Vinyl Ester Resin.

Polymer concrete, which contains silica fume powder and vinyl ester resin as two replacements for Portland cement, has improved mechanical properties and durability compared to ordinary concrete. Thus, this kind of concrete is considered to be a high-strength concrete that is resistant to corrosion and chemical attacks. In this paper, the effects of the combination of silica fume powder and vinyl ester resin as two Portland cement replacements on the workability and slump value, initial and final water absorption, compressive and tensile strength, and failure and fracture paths of the polymer concrete have been investigated. All investigations have been based on 16 different polymer concrete mixture designs. The results indicate that the optimum percentages for a combination of silica fume and vinyl ester resin, which has the maximum compressive strength (34.26 MPa) and the maximum tensile strength (4.92 MPa), are a combination of 10% silica fume and 5% vinyl ester resin. To evaluate the durability of polymer concrete, the water absorption of all mixture designs has also been measured. Accordingly, the mixture design, which includes a combination of 15% vinyl ester resin and 5% silica fume, has a minimum initial and final water absorption equal to 0.62% and 1.95%, respectively.

Physical-Mechanical properties of H-10 blocks manufactured in Norte of Santander, Colombia: a case study

This work presents the physical-mechanical properties of two types of H-10 blocks of six holes fabricated in two different companies in Norte de Santander, Colombia to provide a general visualization of the ceramic properties of masonry products base clay. Random samples of H-10 blocks were collected from the selected companies directly from the furnace as part of the experimental procedure, which was used to perform the physical-mechanical tests such as initial and final water absorption, morphology, resistance to compression, and flexion according to the NTC 4017 standard procedure, the results obtained were compared with the values established in the NTC 4205 standard procedure, used as non-structural masonry products for indoor or outdoor use. Finally, the SEM-EDS micrographs exposed the maincharacteristic chemical elements (Al, Si, O), defects on the surface of an H-10 block and the presence of typical phases (Quartz, Kaolinite, Illite, and Hematite) obtained by the XRD technique.

Impact of Fly Ash on Time-Dependent Properties of Agro-Waste Lightweight Aggregate Concrete

The utilization of by-products and waste materials to substitute for the natural or manufactured resources is considered as a practical way to obtain green building materials. In concrete mixtures, amongst the many available options, Fly Ash (FA) as a by-product pozzolan has been used as a partial replacement of cement. As for the aggregates, lightweight agro-waste oil palm shell (OPS) can be used as a replacement to conventional aggregate for the production of lightweight aggregate concrete. The present communication aims to investigate the impact of FA on time-dependent development properties of OPS lightweight aggregate concrete, including density, water absorption, compressive strength up to 120-days, and drying shrinkage up to the age of 365-days under standard moist curing, partially early curing, and non-curing conditions. Additionally, drying shrinkage crack development was investigated. In this study, two series of concrete mixtures with different substitution levels of OPS (0%, 50%, and 100%) and FA were tested. From the obtained results, it was concluded that the incorporation of fly ash in OPS concrete reduces the density and compressive strength values. Dually, the initial and final water absorption values plus the rate of drying shrinkage at early and long-term ages increased. On top of that, a high potential of drying shrinkage crack, especially for mixtures with 100% OPS, was identified.

Reuse of glass waste in the manufacture of ceramic tableware glazes

Today, various studies are carried out to spread the understanding of sustainability. The sustainability of production processes gains importance in corporate areas. In this study, the use of glass waste instead of frit used in glaze compositions in the ceramic industry was evaluated. The chemical and physical properties of glass wastes on samples were examined. The glaze formulations were prepared using 3%, 5%, and 8% by weight of glass waste instead of frit. Glass wastes were added to glaze compositions and 12 different glaze formulation studies were carried out. Transparent, Opaque, and Matte test glazes were prepared with glass waste added glaze formulations, and these glazes were applied to ceramic bodies. SEM (scanning electron microscope) analysis of standard glaze and glass waste added glazes was performed to determine the microstructural and morphological characterizations. Also, surface whiteness, brightness, L*a*b values, glaze flows, harcort test results, and final water absorption values were compared. As a result of the studies, it has been determined that it is appropriate to use 3% glass waste by weight instead of the frit in the production of ceramic tableware.

Alkali-activated slag (AAS) paste: Correlation between durability and microstructural characteristics

This study was aimed at evaluating the effects of alkali activator solution and utilization of silica fume (SF) on durability and microstructural characteristics of alkali-activated ground granulated blast furnace slag (GGBFS) pastes. The pastes were activated with sodium silicate (SS) blended with NaOH (SH) solution with molar concentrations of 8 M, 12 M, and 16 M and SS:SH ratios of 1.0, 2.5, and 4.0. The same mixes were prepared with SF as partial replacement of GGBFS at a dosage of 10% by weight. The initial and final water absorption as well as the electrical resistivity of the specimens were measured. The optimal paste fabricated with 12 M NaOH solution and SS:SH ratio of 2.5 showed the lowest water absorption and the highest electrical resistivity. Inclusion of SF reduced the final water absorption by 29% and increased the electrical resistivity by 62% compared to the same mix without SF. The observations were confirmed by the results of scanning electron microscopy (SEM) where the optimal paste showed a dense matrix with few pores. Furthermore, the chemical composition of the pastes was studied through energy-dispersive spectrometry (EDS) and X-ray diffraction (XRD) analyses. Moreover, the resistance to aggressive environment conditions of the pastes was examined through exposure to 5% hydrochloric acid and nitric acid up to 90 days. Generally, specimens were more resistant to nitrates. The specimens showed about 5–8% increase in their compressive strength compared to the unconditioned specimens during the first 28 days; however, up to 22% reduction in compressive strength was noticed after 90 days of exposure. It was shown that SS:SH ratio has a higher contribution to acid attack resistance of alkali-activated slag (AAS) pastes.

Durability Property of Oil-Palm-Boiler Clinker Lightweight Concrete Based on Water Absorption Test

Utilizing waste material in the construction industry is an effective way to protect the environment and minimize construction cost. Oil-palm-boiler clinker (OPBC) is a waste material obtained by the burning off solid wastes of the palm oil industry during the process of palm oil extraction. This study presents an investigation on the use of OPBC as coarse aggregate in a grade 40 conventional concrete when normal coarse aggregate was fully substituted (by volume) with this porous and lightweight aggregate. Workability of concrete was assessed based on slump test. The development of compressive strength up to 56 days as well as initial and final water absorption were measured. Test results showed that full substitution of normal coarse aggregate with OPBC reduced workability, compressive strength and density of the concrete. However, OPBC concrete has still good workability for casting and also practical favorable 28-day compressive strength. Water absorption test results revealed that OPBC concrete could be considered as good quality concrete in term of durability property.

Preparation and Properties of Coating for Improving Heat and Salt Wet Resistance of Combustible Cartridges

AbstractA combustible cartridge is made of nitrocellulose, wood fibers and resin. It is easy to absorb moisture in a high‐humidity environment and the NC‐based materials may self‐ignite after storage at higher temperature for a long time. A large number of studies have been carried out to improve the surface protection performance of combustible cartridges usually using a general nitrocellulose varnish. But the heat‐resistance of the nitrocellulose varnish coating is poor. In this article, we develop a composite coating that improves the heat‐resistance and salt wet resistance of combustible cartridges. The new composite coating was prepared by adding BN/silane composite particles and non‐ionic surface active reagent Tween 80 into the nitrocellulose varnish by an optimized composition. The high temperature resistant performance and salt tolerance properties effect of the new composite coating for combustible cartridge were investigated by thermogravimetric experiment, muffle furnace experiment and salt wet resistance test. Compared with the control sample, the coated sample by the new composite coating was able to stand for 138 s at a high temperature of 220 °C, increasing the high temperature resistance time by a maximum percentage of 50 %. In a high‐salt environment, the final water absorption percentage was only 0.2944 % when the coated sample is immersed in a high salt content water at 26 °C for three days, increasing the salt wet resistance by a maximum percentage of 70 %. Results show that the new coating using BN/silane composite particle can improve the high temperature resistant performance and salt tolerance properties of combustible cartridges effectively.

Laboratory evaluation of self-compacting fiber-reinforced concrete modified with hybrid of nanomaterials

The idea of using nanomaterials to improve the bonding of fiber and cementitious matrix is a strategy involving simultaneous and effective use of fibers to enhance concrete mechanical properties on the one hand and decreasing concrete permeability by improving microstructure density on the other hand. Successful application of this idea in self-compacting concrete is an efficient solution for successful use of this product in production of unreinforced prefabricated elements. In this research, optimization of mixing plan of fiber concrete including optimal fiber contents, the largest nominal size of aggregate and optimal fiber size was investigated to achieve the best performance. In the first step, laboratory program including self-compacting fresh concrete tests, compressive strength, tensile strength, flexural strength, modulus of elasticity, as well as initial and final water absorption was administered and in the second step, the effect of aluminum oxide nanoparticles and silicon oxide on basalt fiber concrete designs was investigated. Results obtained from flexural strength test showed that, addition of 2 and 3% of nano-silica resulted in an increase in the concrete yield by 21 and 27% compared to non-nanomaterial fiber concrete. Similarly, the use of 2 and 3% of nano-alumina led to increased flexural strength by 10 and 15%. This improvement in the performance of nanoparticles increased the bonding between fiber and cementitious matrix in other mechanical property tests such as tensile splitting strength and modulus of elasticity. Results showed that addition of basalt fibers causes a decrease in the flowability indicators of self-compacting concrete, but it has no significant effect on compressive strength index. Additionally, application of 3% nano-silica and 3% nano-alumina in separate designs resulted in a 19 and 15% decrease in the initial water absorption of concrete, respectively, indicating improved macro, and micrometer densities of fiber concrete.

Metakaolin Influence on Concrete Durability Properties

Mineral admixtures are being used today almost in all concretes partially, to improve workability, engineering properties and also to enhance durability of the concrete. These admixtures are industrial by-products. In the present study, mineral admixture such as metakaolin (MK) is replaced partially in cement to investigate permanence properties of concrete in terms of initial water absorption, final water absorption and confrontation to acid attack. Inorder to identify the durability properties, concrete of M30 grade was prepared. The mineral admixture content was varied from 0% to 30% by volume of cement with 10% gradient. In acid attack, 3% H2SO4 solution is used for curing of specimens and the corresponding weight losses (%) were evaluated for curing periods of 7 days, 14 days and 28 days. Both initial and final water absorptions of the metakaolin-modified concrete have been improved when metakaolin content was increased up to 10% advantageously. And, also weight loss was decreased when metakaolin content varied from 0% to 30%.

Durability Properties of Blast Furnace Slag (BFS)-Modified Concrete

Mineral admixtures are being used today almost in all concretes partially, to improve workability, engineering properties and also to enhance durability of the concrete. These are industries by-products. This paper discusses, blast furnace slag (BFS) was used to study durability properties; namely, initial water absorption, final water absorption and acid attack. To examine the above mentioned properties, M30 concrete was chosen. The BFS content was varied from 0% to 30% by volume of cement with an interval of 10%. In acid attack, specimens were cured in H2SO4 solution about 3% concentration, the corresponding weight losses (%) were evaluated for curing periods of 7, 14 and 28 days. The durability properties of the BFS-modified concrete have been improved when BFS content increased up to 20% advantageously. Weight loss was also decreased.

Quality control of lightweight aggregate concrete based on initial and final water absorption tests

Water absorption test is used to evaluate overall performance of concrete in terms of durability. The water absorption of lightweight concrete might be considerably higher than the conventional concrete due to higher rate of pores in concrete and lightweight aggregate. Oil palm shell is a bio-solid waste in palm oil industry, which could be used as lightweight aggregate in the concrete mixture. The present study aims to measure the initial and final water absorption and compressive strength of oil palm shell lightweight concrete in order to evaluation of quality control and durability performance. Total normal coarse aggregates were substituted with coarse oil palm shell in a high strength concrete mixture. The quality of concrete was then evaluated based on the compressive strength and water absorption rates. The results showed that fully substitution of normal coarse aggregates with oil palm shell significantly reduced the compressive strength. However, this concrete with the 28-day compressive strength of 40 MPa still can be used as structural concrete. The initial and final water absorption test results also showed that this concrete is not considered as a good concrete in terms of durability. Therefore, it is recommended that both compressive strength and waster absorption tests must be performed for quality control of oil palm shell concretes.

High Strength Lightweight Aggregate Concrete using Blended Coarse Lightweight Aggregate Origin from Palm Oil Industry

The benefits of using structural lightweight concrete in construction industry, particularly in high rise buildings, over normal weight concrete are numerous. The main method of producing structural lightweight concrete is the use of lightweight aggregates instead of ordinary aggregates in concrete. Due to the limited resources for natural and artificial lightweight aggregates, the alternative sources for lightweight aggregates should be discovered from industrial wastes. Oil palm shell (OPS) and oil-palm-boiler clinker (OPBC) are two solid wastes from palm oil industry and are available in abundance in tropical regimes. The use of just OPS as coarse lightweight aggregate in concrete mixture has some drawbacks for concrete. The aim of this study was to investigate engineering properties of a lightweight concrete containing both of these aggregates. For this purpose, in this study, 50% (by volume) of OPS was replaced with OPBC in an OPS lightweight concrete. The test results showed that when OPS was substituted with OPBC, significant improvement was observed in the compressive, splitting tensile and flexural strengths. In addition, initial and final water absorption as well as drying shrinkage strain of blended coarse lightweight aggregate concrete were significantly less than OPS concrete.

The effect of silica fume on durability of alkali activated slag concrete

The effect of substitution the slag with silica fume on compressive strength and permeability of alkali activated slag concrete has been examined and analyzed in this study. The use of alkali activated slag concrete is one of the strategies for production of environmentally friendly concrete which is produced through activation of adhesion feature of blast furnace slag in an alkaline solution. Alkali activated slag concrete with a proper mixture shows superior mechanical properties and durability compared to traditional normal Portland cement concrete. For cases in which AAS concrete with higher performance and durability is needed, AAS concrete with silica fume can be considered as a possible alternative. Since the permeability plays an effective role in concrete durability, this research was carried out to examine the effect of using silica fume on permeability of alkali activated slag concrete by substitution of three levels of silica fume including 5wt%, 10wt% and 15wt% of slag. The effects of two types of curing conditions including water curing and curing under plastic cover were also examined. Short-term and final water absorption, penetration of chloride ion and depth of penetration of water were measured to examine the permeability. The effect of these factors on compressive strength was examined and the relation between compressive strength and passing electrical charges and depth of water penetration was also evaluated. To contrast the use of silica fume on internal characteristics of concrete, samples were observed by scanning electron microscopy (SEM). The results showed that the application of silica fume could increase compressive strength and reduce the permeability of alkali activated slag concrete and water curing was the most appropriate type of curing.

Hard Red Winter Wheat/Nutrim-OB Alkaline Fresh Noodles: Processing and Texture Analysis

ABSTRACT: Nutrim was added at 10%, 20%, and 30% to Hard Red Winter wheat flour to increase soluble fiber content of fresh noodles to a minimum of 0.75 g/noodle serving (one noodle serving is 42 g or 40 g db (dry basis). The effect of Nutrim on the dough characteristics and noodles quality was tackled. The presence of Nutrim increased the final water absorption and dough tolerance as measured by Farinograph whereas the dough stability was decreased. The DSC (Deferential scanning Calorimetry) data showed that Nutrim increased the onset or peak temperatures while the ΔH was reduced by 25%. The resilience of Nutrim-enriched noodles was not significantly affected. The chewiness and hardness were reduced by Nutrim added at 20% and 30%, while cohesiveness was significantly increased by all 3 Nutrim levels. RVA (Rapid Visco Amylograph) profile showed higher peak viscosity in the presence of Nutrim. The 20% and 30% Nutrimlevels increased the soluble fiber of the final product from 1.13% to 1.67% and 2.47%. The yellow color of noodles became darker with higher Nutrim amounts added. The addition of Nutrim produced dough with a more compact image with less space between the starch granules as measured by scanning electron microscopy when compared with the control. The rheological testing showed that the presence of Nutrim decreased flour suspension elastic properties.