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Due to the brittle nature of ceramic, the ceramic and construction industry produces a large volume of waste that imposes a severe environmental threat due to its non-biodegradability. In this study, the suitability of ceramic waste as a replacement of natural coarse and fine aggregate in concrete has been investigated by evaluating engineering properties such as bulk density, water absorption, workability, etc. with respect to different concrete samples made with different mix proportions. Furthermore, a prediction model is introduced to predict compressive and splitting tensile strength using the machine learning tool support vector machine (SVM). A data set containing 108 records either for compressive or tensile strength was used for the training and testing purposes of the SVM model. A total of 9 mix proportions was selected and cast cylinders were cured for 7, 28, and 56 days. Four different kernel functions were used to optimize the results and different accuracy parameters like the value of R2, mean absolute error, mean square error, root mean square error, etc. were compared to find the best kernel function for this study. By primarily evaluating the coefficient of determination (R2), SVM showed an acceptable result with an accuracy of over 90%. Moreover, in terms of other accuracy measurement parameters result indicates that the SVM is an effective tool to predict the compressive and splitting tensile strength of concrete comprised of different proportions of ceramic content.

Due to the brittle nature of ceramic, the ceramic and construction industry produces a large volume of waste that imposes a severe environmental threat due to its non-biodegradability. In this study, the suitability of ceramic waste as a replacement of natural coarse and fine aggregate in concrete has been investigated by evaluating engineering properties such as bulk density, water absorption, workability, etc. with respect to different concrete samples made with different mix proportions. Furthermore, a prediction model is introduced to predict compressive and splitting tensile strength using the machine learning tool support vector machine (SVM). A data set containing 108 records either for compressive or tensile strength was used for the training and testing purposes of the SVM model. A total of 9 mix proportions was selected and cast cylinders were cured for 7, 28, and 56 days. Four different kernel functions were used to optimize the results and different accuracy parameters like the value of R2, mean absolute error, mean square error, root mean square error, etc. were compared to find the best kernel function for this study. By primarily evaluating the coefficient of determination (R2), SVM showed an acceptable result with an accuracy of over 90%. Moreover, in terms of other accuracy measurement parameters result indicates that the SVM is an effective tool to predict the compressive and splitting tensile strength of concrete comprised of different proportions of ceramic content. [ABSTRACT FROM AUTHOR]

The construction industry has a significant environmental impact and concrete production is responsible for a large part of CO2 emissions and energy consumption. This study focused on the reutilisation of a specific type of tiles ceramic waste (TCW), composed only of stoneware and porcelain stoneware tiles, hereafter referred to as ceramic stoneware (CS), as recycled aggregate in concrete. Natural limestone and CS aggregates (sand and gravel) were characterised (particle size distribution, water absorption, resistance to wear, density and X-ray diffraction analyses) and recycled aggregate concrete (RAC) was prepared by replacing 20, 50 and 100 vol.% of sand and gravel, separately. Concrete workability generally improved with CW addition, especially when replacing natural gravel. Although the compressive strengths of the concrete specimens prepared with recycled sand were slightly lower than those of the reference specimens, similar or better results were recorded with the recycled CS gravel. In consonance, the RAC developed with recycled gravel obtained lower water penetration depths than the reference concrete. No significant variation in tensile strength was observed when varying CS content (values within the 2.33–2.65 MPa range). The study contributes to sustainable construction practices and circular economy by promoting the valorisation and reutilisation of industrial waste and reducing the consumption of natural resources. [ABSTRACT FROM AUTHOR]

The construction industry has a significant environmental impact and concrete production is responsible for a large part of CO2 emissions and energy consumption. This study focused on the reutilisation of a specific type of tiles ceramic waste (TCW), composed only of stoneware and porcelain stoneware tiles, hereafter referred to as ceramic stoneware (CS), as recycled aggregate in concrete. Natural limestone and CS aggregates (sand and gravel) were characterised (particle size distribution, water absorption, resistance to wear, density and X-ray diffraction analyses) and recycled aggregate concrete (RAC) was prepared by replacing 20, 50 and 100 vol.% of sand and gravel, separately. Concrete workability generally improved with CW addition, especially when replacing natural gravel. Although the compressive strengths of the concrete specimens prepared with recycled sand were slightly lower than those of the reference specimens, similar or better results were recorded with the recycled CS gravel. In consonance, the RAC developed with recycled gravel obtained lower water penetration depths than the reference concrete. No significant variation in tensile strength was observed when varying CS content (values within the 2.33–2.65 MPa range). The study contributes to sustainable construction practices and circular economy by promoting the valorisation and reutilisation of industrial waste and reducing the consumption of natural resources.

The paper presents the results obtained in the course of a study on the concrete made of aggregate obtained from wastes of sanitary ceramics. Previous examinations proved high in strength and durability of concrete of this type, and it showed a resistance to high temperatures. The material was classified as a fireproof concrete. While searching for the optimal applications of such concrete, a series of examinations and analyses on its thermal energy storage (TES) properties were performed. This paper describes the two-stage experiment on the thermal behavior of the concrete made with sanitary ceramic wastes during cooling processes in comparison to different building materials subjected to the same thermal conditions. On the basis of the thermal, infrared analysis, and suitable calculations, the thermal power and the ability of the composite to store thermal energy was estimated. Finally, it was stated that the concrete made of sanitary ceramic waste aggregate and alumina cement can be recommended as a heat-accumulating material, and in combination with high durability can be used, e.g., for the construction of fireplace bodies. [ABSTRACT FROM AUTHOR]

This experimental and analytical investigation is conducted to develop a sustainable recycled concrete by incorporating ceramic waste as coarse aggregate. In order to achieve the designed goal, conventional aggregate is replaced by different amounts of ceramic waste aggregate. Fresh and hardened properties of conventional as well as ceramic waste aggregate concrete are assessed. Environmental impacts are also considered in terms of CO 2 footprints and consumption of volume of raw materials by concrete. Interfacial model is proposed at micro level to evaluate the behavior of ceramic waste and conventional aggregate with hydrated cement paste. Finally, sustainable concrete is selected which has the best performance with respect to compressive strength and environmental impacts. It is concluded that 30% partial replacement of ceramic waste aggregate with conventional aggregate provides the highest compressive strength, less environmental impacts and is selected as sustainable concrete, which is also verified by analytical hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS) [ABSTRACT FROM AUTHOR]

• Ceramic waste aggregate and clay brick waste powder were used to produce the concrete. • The Taguchi method and Box–Behnken design were applied to the experimental design. • The optimal mixture for maximum compressive strength was found. • The durability of concrete with optimal mixtures was studied. This study investigated the compressive strength and durability of concrete containing clay brick waste powder (CBWP) and ceramic waste aggregate (CWA). First, we applied the Taguchi and Box–Behnken design method to find the optimal conditions for ensuring the maximum compressive strength of concrete. We considered three factors, including the amount of CWA, the amount of CWBP, and the water–cement ratio in the concrete mixture, as factors influencing the compressive strength of concrete. Second, we studied the durability of concrete with optimal mixture. The experimental results showed that the factor that most influenced compressive strength was the amount of CBWP as a cement substitute. The amount of CWA had the least effect on compressive strength. Maximum compressive strength was reached when 100% CWA was used as a coarse aggregate. The compressive strength of concrete containing CWA and CBWP decreased after 7 days but increased again after 28 days. Moreover, the use of CWA and CBWP improved the chloride ion permeability and sulphate resistance of the concrete compared to the control concrete. Meanwhile, the concrete containing CWA and CBWP had lower abrasion resistance than the reference concrete. [ABSTRACT FROM AUTHOR]

Ceramic waste aggregates (CWAs) were made from electric porcelain insulator wastes supplied from an electric power company, which were crushed and ground to fine aggregate sizes. The CWA mortar as an eco-efficient has been investigated containing ground granulated blast-furnace slag (GGBS). The water-to-binder ratio (W/B) of the CWA mortars was varied at 0.4, 0.5, and 0.6. The GGBS, which enhances the chloride ingress resistance, was utilized as a supplementary cementitious material. The CWA mortars partially replaced by the GGBS at 20% and 40% were immersed into a 5% NaCl solution for 48 and 96 weeks. The chloride diffusion and the pore size distribution were assessed by using an electron probe microanalysis (EPMA) and a mercury intrusion porosimetry at each immersion time. The resistance to the chloride ingress of the CWA mortar was effective in proportion to the GGBS replacement level. The changing of the apparent chloride diffusion coefficients except for the CWA without the GGBS at the W/B of 0.6 was small along the immersion time. Moreover, the apparent chloride diffusion coefficient was well related to the cumulative pore volume less than 0.1 µm of pore diameter. [ABSTRACT FROM AUTHOR]

The paper presents the results obtained in the course of a study on the concrete made of aggregate obtained from wastes of sanitary ceramics. Previous examinations proved high in strength and durability of concrete of this type, and it showed a resistance to high temperatures. The material was classified as a fireproof concrete. While searching for the optimal applications of such concrete, a series of examinations and analyses on its thermal energy storage (TES) properties were performed. This paper describes the two-stage experiment on the thermal behavior of the concrete made with sanitary ceramic wastes during cooling processes in comparison to different building materials subjected to the same thermal conditions. On the basis of the thermal, infrared analysis, and suitable calculations, the thermal power and the ability of the composite to store thermal energy was estimated. Finally, it was stated that the concrete made of sanitary ceramic waste aggregate and alumina cement can be recommended as a heat-accumulating material, and in combination with high durability can be used, e.g., for the construction of fireplace bodies.

The characteristics of chloride ingress into mortar containing ceramic waste aggregate (CWA) were investigated by using an electron probe micro-analyzer. The CWA was produced from electric porcelain insulator wastes via the processes of crushing and grinding. The CWA mortar in which entire fine aggregate was replaced with the CWA was studied in comparison with typical river sand (RS) mortar. For both mortars, the water to cement ratio (W/C) was varied at 0.4, 0.5, and 0.6. The chloride ingress was introduced to the mortars through the immersion in a 5.0 wt% sodium chloride solution for 24, 48, and 96 weeks. It is clearly evident that the CWA mortar had smaller chloride penetration than the RS mortar. Furthermore, to manifest how the CWA reduced the chloride ingress, either the pore size distribution of the CWA and the RS mortars or the zeta potential on the CWA and the RS particles in a high-alkaline solution simulating the pore solution was conducted. The CWA mortars had much lower pore volume than the RS mortars, whereas the zeta potential of both particles was not markedly different. It was thus indicated that the pore size distribution is of greater influence than the zeta potential. [ABSTRACT FROM AUTHOR]

Abstract: From our previous findings, the recycling of ceramic waste aggregate (CWA) in mortar has been proved an ecological means plus an excellent outcome against chloride ingress. The CWAs were porcelain insulator wastes supplied from an electric power company, which were crushed and ground to fine aggregate sizes. In this study, to further develop the CWA mortar as an eco-efficient construction material, ground granulated blast-furnace slag (GGBS) was incorporated. The slag (having the Blaine fineness of 6230cm2/g) was utilized as a supplementary cementitious material (SCM) at three different replacement levels of 15%, 30%, and 45% of cement by weight. The efficiency of the GGBS on enhancing chloride resistance in the CWA mortars was experimentally assessed by using a silver nitrate solution spray method and an electron probe microanalysis (EPMA). The tests were carried out on mortar samples after immersed in a 5.0% NaCl solution for 24weeks. Another set of the mortar samples was exposed to a laboratory ambient condition for 24weeks and then followed with a carbonation test. The test results indicated that the resistance to the chloride ingress of the CWA mortar becomes more effective in proportion to the replacement level of the GGBS. In contrast, the carbonation depth of the CWA mortar increases with the increase of the GGBS. The activeness of the GGBS was also evaluated on the basis of the compressive strength development up to 91days. Due to its high fineness, the GGBS can be used up to 30% while the high relative strength (more than 1.0) is achieved at all ages. [Copyright &y& Elsevier]

Abstract: In this study, the chloride ion penetration tests on mortars made of ceramic waste aggregates (CWAs) was conducted by using a silver nitrate (AgNO3) solution spray method and a rapid chloride migration test (steady-state condition). The CWAs used in the experiment are ceramic electrical insulator wastes supplied by an electric power company in Japan, which were crushed and ground to various sizes prior to the replacement of fine aggregates. The influence of the CWAs was evaluated through the tests on four series of mortar as follows: (1) mortars made of different fine aggregates, (2) mortars made of the CWA having a different range of particle sizes, (3) mortars made of the CWA at a different quantity, and (4) mortars made of the CWA at a different replacement ratio. From the experimental results, it is found that the CWA mortars are more effective in the resistance of chloride ion penetration than a typical mortar made of river sand. The depth of chloride ion penetration in the CWA mortars is decreased either when the amount of the CWA is increased or the particle size of the CWA is decreased. In addition, the effective chloride diffusion coefficient of the CWA mortar is lower than that of the river sand mortar. [Copyright &y& Elsevier]

• Clay brick waste powder can be used as a mineral addition in mortar. • Ceramic waste aggregate is a non-active aggregate in terms of alkali-silica reaction. • Decreased flow spread of mortar was observed. • A rough texture of ceramic waste aggregate improved compressive strength of mortar. • Clay brick waste powder improved compressive strength of mortar in long term. This study investigates the potential use of clay brick waste powder (CBP) and ceramic waste aggregate (CWA) in mortar. Cement was replaced by CBP in the mortar mixtures at four ratios (10, 20, 30 and 40 wt%). Meanwhile, CWA was used as a substitute for river sand in the mortar at two levels (50 and 100 wt%). The results demonstrated that the flow spread of the mortars made of CBP and CWA declined sharply owing to the rough and multi-angle texture of their surface. The compressive strength of the mortars decreased slightly at early ages but noticeably improved long term. [ABSTRACT FROM AUTHOR]

Construction and demolition waste material is of great potential for use in pavement engineering. This paper aims to investigate the feasibility of ceramic waste aggregate (CA) used in cooling asphalt pavement through a series of test methods and simulation techniques. Stone mastic asphalt (SMA) containing 10%, 20%, 30%, 40%, and 50% coarse ceramic waste aggregate (CASMAs) was first designed using the Marshall method. Afterward, the road performance and thermal insulation performance of the five different CASMAs were assessed by a comprehensive lab test, including a wheel rutting test, moisture susceptibility test, bending beam test, fatigue beam test, and indoor thermal insulation test. Finally, a 2D finite-element (FE) model was developed to investigate the transient thermal field and rutting deformation response of the cooling asphalt pavement with CASMAs. Results show that CASMAs experienced degradation of rutting resistance, moisture susceptibility, and anti-cracking performance while still meeting technical requirements with CA content of up to 40%. On the other hand, CASMAs can cool the pavement's temperature by 11.5 °C at the bottom of asphalt layers. The permanent rutting deformation of cooling asphalt pavement was 45.36% smaller than that of conventional asphalt pavement without CASMAs. Based on the test results and numerical simulation results, the optimum content of ceramic waste aggregate in stone mastic asphalt was recommended as 40%. [ABSTRACT FROM AUTHOR]