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Prinya Chindaprasirt - One of the best experts on this subject based on the ideXlab platform.

  • autogenous and drying shrinkages of Mortars and pore structure of pastes made with activated binder of calcium carbide residue and fly ash
    Construction and Building Materials, 2020
    Co-Authors: Saofee Dueramae, Prinya Chindaprasirt, Weerachart Tangchirapat, Chai Jaturapitakkul, Piti Sukontasukkul
    Abstract:

    Abstract Present study evaluates the strength development and shrinkage characteristics of Mortars made with a non-cement binder composed of calcium carbide residue and fly ash under several activation techniques. The activation techniques used for improving the strength development were adding NaOH to the binder (0.5, 1.0, and 1.5% by weight of binder), curing at a temperature of 60 °C, and combining both adding NaOH and curing at a temperature of 60 °C. The compressive strengths of Mortars were examined at 3, 7, 28 and 90 days. The shrinkage characteristics of the Mortars were evaluated in terms of the autogenous and drying shrinkages. The pore structure of the paste was also analyzed using mercury intrusion porosimetry. The results showed that all of the activation techniques could enhance the compressive strength of Mortar and improve the pore structure of the paste made from the mixture of calcium carbide residue and fly ash. The technique to improve strength by combining addition of NaOH and curing at 60 °C was found to be the most effective method, and produced the Mortar with a compressive strength as high as 51.1 MPa at 90 days. The shrinkage behaviors of the Mortar made from the mixture of calcium carbide residue and fly ash were similar to the ordinary Portland cement Mortar. The autogenous shrinkage was associated with the internal reaction process, while the drying shrinkage was depended on evaporation of water in pore structures during the drying process. Additionally, the use of NaOH as an activator significantly increased the magnitude of the autogenous and drying shrinkages of Mortar. However, the drying shrinkage was greatly reduced with the activation by curing at 60 °C.

  • strength porosity and corrosion resistance of ternary blend portland cement rice husk ash and fly ash Mortar
    Construction and Building Materials, 2008
    Co-Authors: Prinya Chindaprasirt, Sumrerng Rukzon
    Abstract:

    Abstract This paper presents a study of the strength, porosity and corrosion resistance of Mortars made with ternary blends of ordinary Portland cement (OPC), ground rice husk ash (RHA) and classified fly ash (fine fly ash, FA). Compressive strength, porosity and accelerated corrosion with impressed voltage (ACTIV) were tested. The results show that the use of ternary blend of OPC, RHA and FA produces Mortars with improved strengths at the low replacement level with RHA and FA and at the later age in comparison to that of OPC Mortar. The porosity of Mortar containing pozzolan reduces with the low replacement level of up to 20% of pozzolan, but increases with the 40% replacement level. The chloride induced corrosion resistance of Mortar as measured by ACTIV is, however, significantly improved with the use of both single pozzolan and the ternary blend OPC, RHA and FA. The corrosion resistance of ternary blend Mortar is higher than that of Mortar containing single pozzolan. The use of ternary blend OPC, RHA and FA is very effective in enhancing chloride induced corrosion of Mortar.

  • strength and chloride penetration of Mortar with mixture proportioning in ternary cementitious system
    วารสารวิจัยและพัฒนา มจธ., 2008
    Co-Authors: Sumrerng Rukzon, Prinya Chindaprasirt
    Abstract:

    This paper presents a study of the strength and chloride penetration of blended Portland cementMortar containing classified fly ash (FA) and ground palm oil fuel ash (POA). Ordinary Portland cementtype I (OPC) was partially replaced with FA and POA at the dosage of 0–40% by weight of cementitiousmaterials. In addition to normal replacement, a blend of different weight portion of FA and POA was alsoused to study the combined effect of the FA and POA. Sand–to–binder ratio of 2.75 by weight and water tobinder ratio of 0.5 were used. Superplasticizer (SP) was incorporated in order to obtain Mortar mixes withsimilar flow of 110 ± 5%. FA and POA with 1–3% by weight retained on a sieve No. 325 were used.Compressive strength and chloride penetration depth of Mortars were determined. The results revealed thatthe use of FA and POA produced high strength Mortars. The strength of Mortar containing 10% and 20% ofpozzolans and blended of pozzolans were higher than that of OPC Mortar at all ages. In addition, the use ofternary blended of OPC, FA and POA also produced high strength Mortars and excellent resistance tochloride penetration. Keywords : Strength / Chloride / Fly Ash / Palm Oil Fuel Ash / Mortar

Sumrerng Rukzon - One of the best experts on this subject based on the ideXlab platform.

  • strength porosity and corrosion resistance of ternary blend portland cement rice husk ash and fly ash Mortar
    Construction and Building Materials, 2008
    Co-Authors: Prinya Chindaprasirt, Sumrerng Rukzon
    Abstract:

    Abstract This paper presents a study of the strength, porosity and corrosion resistance of Mortars made with ternary blends of ordinary Portland cement (OPC), ground rice husk ash (RHA) and classified fly ash (fine fly ash, FA). Compressive strength, porosity and accelerated corrosion with impressed voltage (ACTIV) were tested. The results show that the use of ternary blend of OPC, RHA and FA produces Mortars with improved strengths at the low replacement level with RHA and FA and at the later age in comparison to that of OPC Mortar. The porosity of Mortar containing pozzolan reduces with the low replacement level of up to 20% of pozzolan, but increases with the 40% replacement level. The chloride induced corrosion resistance of Mortar as measured by ACTIV is, however, significantly improved with the use of both single pozzolan and the ternary blend OPC, RHA and FA. The corrosion resistance of ternary blend Mortar is higher than that of Mortar containing single pozzolan. The use of ternary blend OPC, RHA and FA is very effective in enhancing chloride induced corrosion of Mortar.

  • strength and chloride penetration of Mortar with mixture proportioning in ternary cementitious system
    วารสารวิจัยและพัฒนา มจธ., 2008
    Co-Authors: Sumrerng Rukzon, Prinya Chindaprasirt
    Abstract:

    This paper presents a study of the strength and chloride penetration of blended Portland cementMortar containing classified fly ash (FA) and ground palm oil fuel ash (POA). Ordinary Portland cementtype I (OPC) was partially replaced with FA and POA at the dosage of 0–40% by weight of cementitiousmaterials. In addition to normal replacement, a blend of different weight portion of FA and POA was alsoused to study the combined effect of the FA and POA. Sand–to–binder ratio of 2.75 by weight and water tobinder ratio of 0.5 were used. Superplasticizer (SP) was incorporated in order to obtain Mortar mixes withsimilar flow of 110 ± 5%. FA and POA with 1–3% by weight retained on a sieve No. 325 were used.Compressive strength and chloride penetration depth of Mortars were determined. The results revealed thatthe use of FA and POA produced high strength Mortars. The strength of Mortar containing 10% and 20% ofpozzolans and blended of pozzolans were higher than that of OPC Mortar at all ages. In addition, the use ofternary blended of OPC, FA and POA also produced high strength Mortars and excellent resistance tochloride penetration. Keywords : Strength / Chloride / Fly Ash / Palm Oil Fuel Ash / Mortar

Pusit Lertwattanaruk - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of nitric and acetic acid resistance of cement Mortars containing high-volume black rice husk ash.
    Journal of environmental management, 2014
    Co-Authors: Burachat Chatveera, Pusit Lertwattanaruk
    Abstract:

    This paper presents the performance of cement Mortar containing black rice husk ash (BRHA) under nitric and acetic acid attacks. The BRHA, collected from an electrical generating power plant that uses rice husk as fuel, was ground using a grinding machine. The compressive strength loss, weight loss, and expansion of Mortars under nitric and acetic acid attack were investigated. The test results of BRHA properties in accordance with the ASTM C 618 standard found that the optimal grinding time was 4 h as this achieved a Blaine fineness of 5370 cm(2)/g. For parametric study, BRHA were used as a Portland cement Type 1 replacement at the levels of 0%, 10%, 20%, 30%, 40%, and 50% by weight of binder. The water-to-binder ratios were 0.55, 0.60, and 0.65. From test results, when the percentage replacements of BRHA in cement increased, it was observed that the strength loss and weight loss of Mortars containing BRHA under acetic acid attack were higher than those of the Mortars against nitric acid attack. It was found that, of the various BHRA Mortars, the strength loss and weight loss due to nitric and acetic acid attacks were the lowest in the Mortar with 10% BRHA replacement. For 10%, 20% and 30% BRHA replacements, the rate of expansion of the BRHA Mortar decreased when compared with the control Mortar. For the Mortars with other percentage replacements of BRHA, the rate of expansion increased. Furthermore, the effective water-to-binder ratios of control and BRHA Mortars were the primary factor for determining the durability of Mortar mixed with BRHA.

  • Utilization of ground waste seashells in cement Mortars for masonry and plastering
    Journal of environmental management, 2012
    Co-Authors: Pusit Lertwattanaruk, Natt Makul, Chalothorn Siripattarapravat
    Abstract:

    In this research, four types of waste seashells, including short-necked clam, green mussel, oyster, and cockle, were investigated experimentally to develop a cement product for masonry and plastering. The parameters studied included water demand, setting time, compressive strength, drying shrinkage and thermal conductivity of the Mortars. These properties were compared with those of a control Mortar that was made of a conventional Portland cement. The main parameter of this study was the proportion of ground seashells used as cement replacement (5%, 10%, 15%, or 20% by weight). Incorporation of ground seashells resulted in reduced water demand and extended setting times of the Mortars, which are advantages for rendering and plastering in hot climates. All Mortars containing ground seashells yielded adequate strength, less shrinkage with drying and lower thermal conductivity compared to the conventional cement. The results indicate that ground seashells can be applied as a cement replacement in Mortar mixes and may improve the workability of rendering and plastering Mortar.

Prabir Kumar Sarker - One of the best experts on this subject based on the ideXlab platform.

  • Effect of waste glass fine aggregate on the strength, durability and high temperature resistance of alkali-activated fly ash and GGBFS blended Mortar
    Construction and Building Materials, 2020
    Co-Authors: Nabi Newaz Khan, Prabir Kumar Sarker
    Abstract:

    Abstract Properties of alkali-activated fly ash and GGBFS blended Mortar using waste glass cullet were investigated. Workability of Mortar was found to increase by glass aggregate due to its lower absorption than sand. Compressive strength decreased from 77 MPa to 73 MPa at 90 days of age for replacing 100% sand by glass aggregate. Though porosity increased by 1.5% to 13% for using 25% to 100% glass aggregate, reductions were observed in drying shrinkage, sorptivity and chloride permeability. The minor variations in Mortar properties are attributed to the lower permeability and irregular shape of glass aggregate. Mortars using glass aggregate showed similar trend of residual strength as compared to that using natural sand after 200°C–800°C temperature exposures. Microstructural studies revealed that Mortars using glass aggregate had less microcracks and enhanced bond at the interfacial transition zone (ITZ) after elevated temperature exposures. Moreover, the findings of this study suggests that the replacement of natural sand by using various percentages of waste glass cullet in alkali-activated Mortar offers comparable properties to those using natural sand.

  • Alkali silica reaction of waste glass aggregate in alkali activated fly ash and GGBFS Mortars
    Materials and Structures, 2019
    Co-Authors: Md. Nabi Newaz Khan, Prabir Kumar Sarker
    Abstract:

    This paper evaluates the alkali silica reaction (ASR) susceptibility of waste glass aggregate in alkali activated fly ash and ground granulated blast furnace slag (GGBFS) Mortars as compared to that in ordinary Portland cement (OPC) Mortars. In accelerated Mortar bar tests, glass fine aggregate showed much lower expansions in alkali activated fly ash and GGBFS blended Mortars than in OPC Mortars or alkali activated neat fly ash or GGBFS Mortars. Glass aggregate was classified as non-reactive with alkali activated fly ash and GGBFS blends according to 10-day and 21-day expansion limits of the Australian Standard. Microstructural studies revealed that glass aggregate produced typical ASR products in OPC Mortars and alkali activated neat GGBFS Mortars due to the presence of high calcium. However, alkali activated fly ash and GGBFS blended Mortars produced reaction products of low Ca/Si and high Al/Si ratios that reduced the dissolution of reactive silica present in glass aggregate causing less expansions. The observed expansion of the alkali activated neat fly ash Mortar is attributed to the analcime phase found in the X-Ray diffraction of this Mortar.

Yoshihiko Ohama - One of the best experts on this subject based on the ideXlab platform.

  • strength properties of polymer Mortar panels using methyl methacrylate solution of waste expanded polystyrene as binder
    Construction and Building Materials, 2011
    Co-Authors: Muhammad Aamer Rafique Bhutta, Yoshihiko Ohama, Ken Tsuruta
    Abstract:

    Abstract The present study examines the applicability of polymer Mortar panels using a methyl methacrylate (MMA) solution of waste expanded polystyrene (EPS) to develop effective recycling processes for the EPS, referring to the strength properties of a polymer-impregnated Mortar panel with almost the same performance as commercial products. An MMA solution of EPS is prepared by dissolving EPS in MMA, and unreinforced and steel fiber-reinforced polymer Mortars are mixed using the EPS-MMA-based solution as a liquid resin or binder. Polymer Mortar panels (PMPs) using the EPS-MMA-based polymer Mortars without and with steel fiber and crimped wire cloth reinforcements and steel fiber-reinforced polymer-impregnated Mortar panel (PIMP) are prepared on trial, and tested for flexural behavior under four-point loading. The EPS-MMA-based PMPs are more ductile than the PIMP, and have a high load-bearing capacity. Consequently, they can replace PIMP in practical applications.

  • Polymer-Modified Mortars and Concretes
    Concrete Admixtures Handbook, 1996
    Co-Authors: Yoshihiko Ohama, V.s. Ramachandran
    Abstract:

    Publisher Summary Polymer-modified Mortar and concrete are prepared by mixing either a polymer or monomer in a dispersed, powdery or liquid form with fresh cement Mortar and concrete mixtures, and subsequently cured, and if necessary, the monomer contained in the Mortar or concrete is polymerized in-situ. Several types of the polymer-modified Mortars and concretes— namely, latex-redispersible polymer powder-, water-soluble polymer-, liquid resinand monomer-modified Mortars and concretes are produced by using the polymers and monomer. Of these the latex-modified Mortar and concrete are by far the most widely used cement modifiers. Although polymers and monomers in any form such as latexes, water soluble polymers, liquid resins, and monomers are used in Mortar and concrete, it is very important that both cement hydration and polymer phase formation proceed well to yield a monolithic matrix phase, with a network structure in which the hydrated cement phase and polymer phase interpenetrate into each other. In the polymer-modified Mortar and concrete structures, aggregates are bound by such a co-matrix phase. The superior properties of the polymer-modified Mortar and concrete to conventional Mortar and concrete are characterized by such a distinct structure.