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Suitcase bricks are widely used in the construction sector, due to their resistance, thermal and acoustic capacity; Furthermore, the subsistence of many families dedicated to this activity is involved in its manufacture. However, the potential for contamination in the manufacture of brick due to the burning that they are exposed to brings with it multiple effects that considerably deteriorate the environment every day. Given this problem, this research has been developed those deals with the manufacture of suitcase brick. artisanal by applying various concentrations of cement, for which 8 treatments were carried out with the following percentages of cement (0.10%, 0.25%, 0.5%, 1%, 2%, 4%, 6%, 8% and a control), in which each treatment consisted of 4% bricks and then two of each treatment were exposed to the burning process, to finally compare their resistance between the bricks that were not subjected to this process compared to the brick of Traditional manufacturing, using a four-column compression machine to break concrete specimens, each of the artisanal bricks under study was broken. According to the results obtained, the bricks from the treatment with 4% cement from the burning process showed the result of greater resistance of 121.01 Kgf/cm2, it can also be noted that the treatment with 1% cement without burning processes presented a value of 28.43 Kgf/cm2, which represents more than half the compressive strength of traditional brick with a burning process of 46.51 Kgf/cm2 (Control). [ABSTRACT FROM AUTHOR]

Considering the potential of geopolymer cements as an alternative to partially substitute Portland cement, this article presents a brief review, where the curing conditions of geopolymer cements are analyzed based on three variables: time, humidity, and temperature. In addition, the behavior of these variables is described according to the curing methods that have been studied and evaluated so far in fly ash-based geopolymer cements. The literature review was conducted using Scopus as the primary search tool, starting from the keyword 'geopolymeric cements.' More than 90 relevant documents were identified after applying specific filters and reviewing their abstracts. Finally, a thorough reading, and analysis of the bibliographic data were performed to extract relevant information for the study topic. The published procedures show that there is no conclusive trend in the curing method for this type of material; however, the most accepted conditions for the development of higher compressive strengths are temperatures between 60 and 80 °C, with controlled humidity (sealed), for a period of 4 to 12 hours. In general, this brief review serves as a guide to propose, study, and apply different curing processes in fly ash-based geopolymer cements. [ABSTRACT FROM AUTHOR]

The research arose from the need to reduce the environmental and sanitary impact caused by the inadequate disposal of tires and rubber when they reach the end of their useful life. Initially, the collection and recycling of tires and rubber was carried out, which after going through a shredding process were reduced to smaller particles, which also served as plastic sand as a guarantee for sustainable pavement. Each dosage was evaluated by performing unit mass, moisture, absorption, specific gravity and compressive strength tests. These tests allowed determining the feasibility of using GCR as an alternative raw material in civil works, thus offering a different option for the substitution of fine aggregate in the production of pavement. [ABSTRACT FROM AUTHOR]

Concrete has long been a crucial material in civil engineering projects. Improving it is key to enhancing its efficiency and resistance to various forces. This study focuses on how the addition of synthetic and steel fibers influences the flexural strength of self-compacting concrete. Through the creation of concrete beams, flexural tests, and fiber analysis are conducted. It is observed that synthetic fibers minimally enhance flexural strength but increase resistance to rupture and cracking. Steel fibers offer a significant increase in flexural strength. Fiber distribution revealed segregation at the top of the beams, where flexural strength was higher. These findings support the importance of carefully considering additional materials to enhance the efficiency and durability of concrete in civil engineering projects. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Odontología Universidad de Antioquia is the property of Universidad de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The global increase in walnut production has resulted in significant waste generation, typically ending up in landfills and causing adverse environmental impacts. The waste occupies large land areas and contaminates the soil through decomposition processes. Chile, known for being a major producer of walnuts, particularly the Chandler variety, possesses a valuable waste resource in the form of walnut shells. These shells can be utilized as raw material in the manufacturing of innovative construction materials. This article focuses on determining the absorption, swelling, density, flexural strength, and compressive strength properties of prismatic samples made from Chandler walnut shells. These samples were bonded using two types of PVAc adhesives: one commonly used for wood joints, and another specifically designed for moisture resistance. The results demonstrate the viability of this particleboard, showcasing its stability and ability to withstand moderate stress. [ABSTRACT FROM AUTHOR]

In the present study, the development of pigmented cement mortar for outdoor applications, aiming to replace traditional finishes, especially in pool settings, was investigated. The study used the properties of workability, particle size, and strength from a commercial sample (CS) as a reference, complying with regulations for pool finishes. In the initial stage, the additive/binder (A/B) and water/cement (W/C) ratios were varied to achieve workability similar to the CS reference. Compression strength and porosity were evaluated as response variables according to ASTM C642 standards at 1, 7, and 28 days of curing. In a subsequent stage, the aggregate/cement ratio was reduced to enhance mechanical performance and reduce porosity. Additionally, colorants were introduced, and compression strength at 1, 7, and 28 days, three-point flexural strength, and the percentage of permeable pores at 28 days were assessed. Pigmented mortars exhibited compressive strengths exceeding 35 MPa, flexural strengths exceeding 5 MPa, and a volume percentage of pores below 8% after 28 days of curing. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the compressive strength of concrete cylinders reinforced with expanded metal meshes. The investigation aims at comparing the compressive strength of concrete specimens strengthened with expanded metal meshes with different orientations. A series of compression tests were performed to obtain the structural performance on jacketed specimens, and then compare these with the unreinforced concrete cylinders. Expanded metal tubes were fabricated using circular geometries with two cell orientations. The results showed that cell orientation enhance the compressive strength of the specimens. [ABSTRACT FROM AUTHOR]

Copyright of Tecnura is the property of Tecnura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article focuses on the utilization of additions such as microsilica (MS), metakaolin (MK), and calcium carbonate (CaCO3) for the design of cementitious materials based on ordinary Portland cement (OPC) suitable for 3D printing (additive manufacturing). The additions were incorporated into the mixes as replacements for OPC in quantities of 5-10% (MS), 5-15% (MK), and 5-15% (CaCO3). The effect of the additions on the fresh and hardened state properties of the mixes was evaluated. The properties studied included extrusion capability, workability (mini slump), flowability (flow table test), setting time, open time, and printability. Additionally, microscopic inspection of the 3D printing mixes was conducted using scanning electron microscopy (SEM), and physical-mechanical characterization was performed through tests for density, absorption, porosity, flexural strength, and compressive strength. The results demonstrated that the additions directly influence the aforementioned properties. It was concluded that the mix 90%OPC-5%MS-5%CaCO3 (mixture 1) and the mix 90%OPC-5%MS-5%MK (mixture 2) exhibited the most suitable set of characteristics to be implemented as 3D printing cementitious materials. From these mixes, it was possible to 3D print beam-type specimens (160 x 40 x 40 mm), achieving flexural strength values at 28 days of 3.4 MPa (mixture 1) and 4.0 MPa (mixture 2), and compressive strength values of 44 MPa (mixture 1) and 50 MPa (mixture 2). These results are considered as a starting point for future research related to the use of these types of additions in 3D printing of OPC-based cementitious materials. [ABSTRACT FROM AUTHOR]

Copyright of Dilemas Contemporáneos: Educación, Política y Valores is the property of Dilemas Contemporaneos: Educacion, Politica y Valores and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of UCV Hacer is the property of UCV Hacer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The high consumption of Portland cement (OPC) has a significant impact on the environment due to the generation of greenhouse gases and the use of non-renewable raw materials during its manufacturing. Therefore, the search for alternative materials to reduce cement consumption is crucial in the pursuit of sustainability. For this reason, copper slag (CS) as a supplementary cementitious material (SCM) in the production of mortars with lower OPC content is an option to create a sustainable environment. This study investigated the influence of CS on workability, compressive strength, and flexural strength at different curing ages. Mortars were prepared with 0%, 10%, 20%, 30%, 40%, and 50% CS as partial replacement for OPC, where mortars with CS demonstrated increased flowability. The mechanical properties were monotonically affected during the initial evaluated ages (7, 28, and 90 days), with mortars containing higher CS content showing the greatest loss of strength. However, at 150 days of curing, the 10% CS mixture exhibited a compressive strength of 43.6 MPa, which was 7.6% higher than the reference mixture [ABSTRACT FROM AUTHOR]

The purpose of this paper is to carry out a literature review on the effects of using wood ash as a component in concrete, in order to determine its mechanical properties and behavior. A review of 80 refereed and indexed articles was carried out. The key words were: "concrete and wood ash, replacement of cement with wood ashes, percentages of wood ash in concrete. From this review it is concluded that the use of wood ash provides better physical-mechanical behavior when used in materials such as concrete; however, its adequate percentages range from 5 to 15%, given that in these proportions it has allowed obtaining an increase in relation to the standard concrete of 76% of its compressive strength. [ABSTRACT FROM AUTHOR]

This paper presents the results of the study of the influence of concrete curing in compressive strength in warm-rainy climate. Concrete several specimens were emptied in the laboratory, there were curing by three methods and tested for resistance at the ages of 3,7, 14, 28, 56 and 91 days. Compressive strength in weathering is shown to be associated with environmental factors such as precipitation and temperature. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Adobe is a low-cost building material, widely used in different regions of the world. This study evaluated the potential recovery of sludge from a conventional drinking water treatment plant (DWTP) that uses aluminum sulfate as a coagulant, as a partial replacement of the soil (the main component of adobe). The experimental stages were i. characterization of lime stabilized sludge (thermogravimetric analysis, pH, real density and electrical conductivity) and soil (determination of the plasticity index - PI, liquid and plastic limits and X-ray diffraction-DRx) and in two aggregation conditions (soil coarse and ground); ii. production and characterization of adobe blocks (29x15x10 cm³), placed under shade (28 days of curing) and dried to constant weight, considering a humidity lower than 40% and proportions in weight soil:stabilized sludge:portland-OPC cement defined by the Response Surface Methodology (stabilized sludge: 0.0 - 36.4% and OPC: 0.0 - 9.1%) and iii. comparison of compressive strength (MPa: study response variable). The sludge showed silicoaluminous nature (65.14% non-volatile matter: SiO2, Al2O3 and Fe2O3 in the form of quartz, kaolinite, gibbsite and goethite), pH 6.34 units, real density 2.5 g/mL and conductivity 0.62 µs/cm. The IP (≤7.0) classifies the aluminous sludge as not very plastic and partially cohesive material. The ground soil showed greater potential for using the sludge (ground soil: OPC: mud 54.5: 9.1: 36.4 vs coarse soil: OPC: mud 90.9: 9.1: 0.0) with resistance to compression of 6.01 and 2.10 MPa respectively. These results demonstrate the viability of valorization of DWTP aluminous sludge stabilized with lime and ground for adobe production, contributing to a more sustainable and environmentally friendly production by reducing the use of materials such as soil. [ABSTRACT FROM AUTHOR]

The article presents a study on the creep behavior of high-density polyethylene (HDPE) and examines different methods to predict this behavior using creep tests under tension. Experimental tests were conducted with different processing techniques to investigate the effects of materials and processing techniques on compressive strength. The results show that the time-temperature superposition method is more effective in predicting long-term creep behavior at temperatures of 23 °C. The article concludes that there is no significant difference in the creep behavior of HDPE due to its manufacturing, whether compression molded or blow molded. Additional tests, such as indentation tests, are suggested to predict creep behavior. [Extracted from the article]

Republican masonry is part of the historical heritage of Latin America. However, their behavior in seismic events is not optimal, therefore the conservation of these constructions should consider the improvement of their structural behavior. This research studies the reinforcement with Guadua bamboo mat and analyzes its structural incidence in walls built with units recovered from republican constructions. For the experimental process, walls were built for compression and diagonal tension tests, classified in three groups: walls without reinforcement, walls reinforced with guadua mat, and walls reinforced with guadua mat covered with lime mortar and metakaolin. In the tests, although no increase in strength was observed in the reinforced walls, an increase in strain and ductility was observed. Therefore, the guadua mat represents a viable alternative to improve the behavior of republican structures in seismic events. [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate nutshell ash as a partial substitute for Portland cement type I and its effect on compressive strength. For this purpose, walnut shell ash was considered in proportions of 0 %, 10 % and 15 % in relation to the weight of cement, proceeding to elaborate 50 mm of side which were cured for 7, 14 and 28 days to measure their compressive strength according to the specifications of NTP 334.051:2022. As results, it was found that the dosage for the elaboration of 9 cubes of mortars was 359 cm³ of water and 2035 g of sand for each of the groups where the ash content was varied by 0 g, 67.27 g and 69. 52 g, in addition to cement in 740 g, 672.73 g and 643.48 g; as for the compressive strength it was found that at 28 days for the standard mortar it was 290.28 kgf/cm², where 10 % of walnut shell ash was replaced it was 354. 18 kgf/cm² and for 15 % of walnut shell ash it was 161.11 kgf/cm²; regarding the initial setting time it was found that for the standard mortar it was 152.33 min, where 10 % of ash was used it was 174.67 mm and for 15 % it was 189 min. It can be concluded that 10 % of walnut shell ash as a partial substitute for Portland cement is a suitable element as it increases the compressive strength and delays the setting time of the mortar. [ABSTRACT FROM AUTHOR]

Copyright of Iteckne is the property of Universidad Santo Tomas, Division de Ingenierias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The geomechanical strength of rock masses plays a key role in the planning and design of civil and mining construction projects. The uniaxial compressive strength (UCS) of rocks is a crucial property that is widely used in geotechnical engineering to understand the strength and deformability of rock masses. Determination of geomechanical properties both in the field and in the laboratory is time consuming, tedious, and expensive. However, ultrasonic techniques, such as P-wave propagation velocity (VP) measurement, are a simple, cost-effective, and non-destructive method for evaluating the UCS of rocks. In this study, a review of the state of knowledge of the type of empirical correlations that exist for sandstones to predict the value of UCS from VP is developed. The main objective developed is a meta-study on the relationship between UCS and VP. For this, UCS and VP data for sandstonetype sedimentary rock are compiled from various sources. With the results obtained, empirical formulas are proposed that correlate UCS and VP, which can be used as a geotechnical engineering tool to predict the value of UCS from VP in sandstones. [ABSTRACT FROM AUTHOR]

The investigation has the aim of finding the effect and adequate proportion of the hemp fiber of 4 cm in length, in the mechanical and resistivity properties of a clayey soil. Properties investigated include optimum moisture content (wópt); the maximum dry unit weight, (γdmax), cohesion (c); friction angle (Φ), unconfined compressive strength (qu), and electrical resistivity (ρ). The modified Proctor compaction tests (ASTM D 1557-12), direct consolidated undrained shear, CU, for cohesive soils (ASTM 6528-17), unconfined compressive strength (ASTM D2166-16) and Wenner's four electrode test (ASTM G57-01l), were applied to three clay samples with differentproportions of hemp fiber; standard sample, Ap, of 100 % clay from the city of Tunja, sample with 0.5 % and 0.75 % hemp fiber, A0.5 %, and A0.75 %, in relation to the dry weight of the material. The results of this study indicate that the optimal percentage of hemp is 0.5 %, showing a decrease in compaction, and an increase in shear strength, electrical resistivity properties and unconfined compression properties; nevertheless, with a greater presence of fiber, there is destruction of the clayey soil. [ABSTRACT FROM AUTHOR]

The antifriction alloys known by the generic name of Babbitt and composed of tin as the base metal. In Cuba, this material is currently imported from Russia, so the main objective of this work is to characterise the Cuban-produced Babbitt AVEF1 obtained by centrifugal casting. First of all, a device was built to obtain a babbitt piece by the aforementioned casting process. Then, the specimens were prepared according to the established standards. The microstructure, hardness and compressive strength are studied and compared with the same properties of the Russian babbitt B-83. The microstructure of both materials is found to be similar. Differences in hardness and compressive strength were observed. Therefore, it is concluded that Babbitt B-83 has better properties. The present work represents an advance in the reconditioning process of babbitt sliding bearings in the Cuban industry. [ABSTRACT FROM AUTHOR]

Copyright of Conservar Património is the property of Associacao Profissional de Conservadores-Restauradores de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: expanded polystyrene (EPS) concrete is an environmentally friendly material; however, its compressive strength is lower than traditional concrete, requiring the incorporation of materials that improve its compressive strength. This paper reports the effect of waste glass (WG) incorporation on the properties of concrete containing polystyrene as partial replacement of fine aggregate. Objective: to evaluate the effect of the incorporation of glass residues on the physical and mechanical properties of concrete made from polystyrene. Methodology: concrete was produced with 10 % by volume replacement of fine aggregate. Different EPS:WG volume ratio 1:0, 1:1, 1:2, 1:3 and 1:4 (volume EPS +WG = 10 % volume fine aggregates replacement) were prepared. The slump of fresh mixtures was evaluated, density and compressive strength of hardened concrete at 28 days was evaluated; the durability was assessed through alkali silica reaction test. Results: an increasing in glass content was inversely proportional to slump, additionally, with the incorporation of glass, the density was not significantly affected. The incorporation of waste glass greatly increases the compressive strength, being the EPS:WG 1:3 mixture that showed the highest compressive strength, which was 37.2 % higher than reference concrete (1:0) was. Additionally, in 1:3 mixture was evidenced that the addition of waste glass does not lead to deleterious alkali silica reaction effect. Conclusions: the addition of waste glass to concrete prepared from expanded polystyrene improved its mechanical properties, making it a potential system to replace traditional materials used in concrete production. [ABSTRACT FROM AUTHOR]

It's appropriate mechanical behavior and its low carbon footprint allow bamboo to replace conventional construction materials in various applications. Currently, it should be considered that there are countries that still do not have sufficient knowledge about the structural characteristics of locally grown bamboos. In this sense, this research presents the results for the determination of the geometric properties and the compressive and tensile mechanical properties parallel to the fiber of the species Phyllostachys aurea from the Ecuadorian Amazon. With the samples tested, the compressive strength parallel to the fiber presented a minimum standard deviation in the results, showing an average strength of 52.4 MPa. After a statistical analysis of these values, a normal distribution was observed between them, increasing their reliability; the tensile strength parallel to the fiber showed a high standard deviation in the results, due to the difficulty in preparing the required sample as established in the standard ISO/FDIS - 22157 (2019). However, the average resistance of this parameter was 90.2 MPa, confirming that it is a bamboo with great potential against this type of load. Therefore, a comparison was made between the compressive and tensile strength of the Phyllostachys aurea species with other conventional materials used in construction such as reinforced concrete, structural steel and Guadua angustifolia Kunth bamboo. [ABSTRACT FROM AUTHOR]

The objective here is to determine the influence of the incorporation of recycled rubber in structural concrete and its hypothetical seismic response, developing the investigation under a type of applied investigation, of pure experimental design with a non-probabilistic sample of DBCA method of 84 briquettes that include the standard concrete with a design of 210 kgf/cm2 and concrete with the incorporation of recycled rubber at 2%, 4% and 6%, which were evaluated at 7, 14 and 28 days of age under the technique From direct observation, parameters such as resistance to compression and indirect diametral traction where the results showed that the most optimal incorporation was 4% of both fine and granulated rubber at 28 days in all parameters, surpassing the resistance to compression by 3.76% and 4.14%, as well as the diametral indirect tensile strength by 8.98% and 16.05% with respect to the standard concrete and according to or with the analysis of the hypothetical seismic response with the optimal rubber percentages found, an improvement percentage was determined with the incorporation of 4% rubber, both fine and granulated, in the maximum drifts for the X-X direction 3.44% and 3.87%, as well same for the Y-Y direction of 3.47% and 3.96% respectively compared to the concrete pattern. Thus demonstrating that the use of 4% rubber, both fine and granulated, in concrete is acceptable. [ABSTRACT FROM AUTHOR]

Copyright of Odontología Pediátrica is the property of Asociacion Sociedad Peruana de Odontopediatria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista ION is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of recycled aggregates from construction and demolition waste (CDW) in new civil works is considered a way to sustainable development. This study presents the possibility of using recycled coarse aggregate (RCA) and treated coarse aggregate (TCA) from concrete in self-compacting concretes (SCC). For this purpose, two treatment methods were carried out to AGR, one of the treatments was by mechanical wear in a ball mill and the other was by immersion in an acid solution (H2SO4) combined with mechanical wear. To investigate the effect of different RCAs treatment on the mechanical properties of SCCs, different replacement levels (0%, 20%, 40% and 100% by volume) of natural coarse aggregate (NCA) by AGR and TCA were carried out. In the fresh state, filling ability, passing ability, workability and resistance to segregation were assessed using the Abrams cone (slump flow), V-funnel and L-box, and in the hardened state, tests of compression strength, indirect tensile strength and flexural strength were carried out to the SCCs. The results indicated that the increased proportions of RCA presented a decrease in the performance of the properties in the fresh and hardened state due to the presence of the mortar adhered in this type of aggregates, however, the workability re well-matched with the limitations provided by EFNARC. The SCCs with TCA presented a better performance compared to the SCCs with RCA. The mechanical properties of the SCC with TCA presented a better performance compared to the SCC with RCA, due to the removal of the adhered mortar, improving the compressive strength in all SCC with TCA. In addition, the SCCs with TCA showed improvements in the permeability properties, presenting a reduction in porosity of up to 6.06%. [ABSTRACT FROM AUTHOR]

Large quantities of waste glass are generated every year, and inappropriate disposal creates an increasing problem that needs to be addressed. This research aims to use glass waste as a partial replacement for fine aggregates in the preparation of concretes, to save natural resources and solve environmental pollution problems. Different mixes were produced by replacing fine aggregates with 5%, 10%, 15%, 20%, 25%, and 50% of waste glass. Concrete specimens of 0.15 m in diameter and 0,3 m in length were fabricated and tested in settling and compression strength. The experimental results indicated that the settling decreases with the increase of the percentage of glass. The best specimen (20% replacement) exhibited an increasing 5,5% in compressive strength. The assessment of economic and environmental aspects reveals that the same sample can provide 0,7% savings in cost and 6,4% in emitted carbon dioxide compared with traditional concrete. The results demonstrate that waste glass can replace fine aggregates to manufacture concrete. This approach offers an environmentally friendly solution to the ongoing problem of waste glass. [ABSTRACT FROM AUTHOR]

The mechanical behavior of cement pastes was evaluated using Portland Cement Type II 30R from five brands, to identify the optimal relationship of the cements with different types of sand to make mortars. Five series of pastes and mortars were made with each brand of cement, varying the type of sand per series in the mortars. The resistance of cement pastes is different for each brand. The same brand of cement will have a different behavior depending on the sand used. Sand influences compressive strength. To improve the mechanical performance of the mortar, the component materials are analyzed. A specific mix design optimizes the mortar in construction. [ABSTRACT FROM AUTHOR]

The objective of the research is to determine the effect of the use of recycled PET on the permeability, compressive strength, and flexure of the permeable pavement f'c=280 kg/cm2. The methodology is applied type, experimental design, and quantitative approach. Permeable concrete is a type of porous pavement that seeks to solve the problems of traditional pavements, since traditional pavements, by not having an adequate gutter, tend to accumulate rainwater causing various accidents due to lack of inertia and decrease in pavement life. PET is a material that is found everywhere as waste, this material tends to resist tensile loads. The results show that 0.3% PET improves compressive strength, while 0.4% PET improves flexing and permeability. It is concluded that if the greatest resistance is sought, a lower dosage of PET is used and if greater flexing and permeability is sought, a higher percentage of PET is used. This study showed that PET does have a significant influence on the compressive strength, flexural strength, and permeability of pervious concrete. [ABSTRACT FROM AUTHOR]

It was performed a geomechanically characterization of a guiding tunnel for the exploitation of gold in the Yaraguá mine (Continental Gold Limited) in the Municipality of Buriticá (Antioquia). The characterization process included the classification of the rock mass by the RMR and the Q systems, analysis of thin sections, tests such as the P-wave velocity, the point load test and the uniaxial and triaxial compression tests. The analyzed rocks classify as basalts, andesite, diorite and breccia, all with compound-minerals such as magnetite, carbonates and pyrite. In the wave velocity tests, the rocks have reached 70% of theoretical speed, giving continuity indices in the interval of strong to medium. The uniaxial compressive strength is between 42 MPa and 134 MPa. The behavior of the rocks under the loads in the triaxial compression test shows a fragile to fragile-ductile tendency and its peak resistance are in the interval from 130 MPa to 150 MPa. Finally, upon all these tests, one concludes that there are two types of failure associated with mineralization: either through veins or by sulphide accumulation zones. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia en su PC is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bistua: Revista de la Facultad de Ciencias Básicas is the property of Facultad de Ciencias Basicas de la Universidad de Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present research study examined the optimal conditions for using aluminous sludge, from a drinking water treatment system, as a partial substitute for cement to manufacture non-structural construction materials. Standard mixtures consisted of aluminous sludge (5, 10, 15 and 20%) and cement. At 7, 28, and 42 days, mixtures were examined for granulometry, X-ray fluorescence, organic matter content, humidity, compressive resistance, and absorption. The results showed significant differences with variations in compressive strength between 2.60 and 7.70 MPa. The mixtures with 15 and 20% aluminous sludge were the only ones that met the limits established for non-structural building materials by the ASTM-C129 regulation. In conclusion, introducing aluminous sludge (15 and 20%) as a substitute for cement did not deteriorate material mechanical resistance. [ABSTRACT FROM AUTHOR]

Introduction: the following study focuses on the granulometric analysis of soils, using a soil from the town of Cuauhtémoc, Villa Flores, Chiapas, Mexico, to determine its possible use in the elaboration of Compressed Earth Blocks (CEB). The purpose of the study is to achieve adequate mechanical strength without using chemical stabilization Method: the initial characterization procedure of the soil samples was developed by means of granulometric determination and consistency limits, which made it possible to identify the soil by its granulometric curve and resistance to axial compression. The discussion arose from the identification in the existing regulations for CEB in Spain and Mexico that they establish too wide granulometric intervals and do not seem to give importance to achieving an optimal accommodation of the granulometric curve, forcing chemical stabilization. A granulometric range for CEB was idealized by adjusting maximum and minimum limits of the different sizes of particles that make up the samples and the percentage of initial water was established from the plasticity index. Afterwards, 3 series were elaborated with five samples of compressed earth in each configuration, varying the granulometric curve, percentage of water and elaboration pressure to improve their resistance to compression. Results: the results describe a notable improvement in the behavior of the soil as a compressed block when the granulometric adjustment is carried out. The CEB mix design was improved from 32.5 kg / cm² to 54.75 kg / cm² by adjusting the percentage of water and nominal brewing pressure. Conclusion: it is concluded that it is possible to optimize the use of soil for construction by controlling the granulometry, water content and nominal pressure of the raw material, achieving mechanical strengths greater than 50 kg / cm² without using cement, asphalt, or lime as stabilizers. [ABSTRACT FROM AUTHOR]

To contribute to the solution, we set the objective of making a documentary analysis of research carried out with the use of fluidizing additives, based on copolymers, in order to find concretes that meet market demands. The methodology consisted of making a documentary / bibliographic analysis of research using available search engines. The period from 2017 to March 2021 was used as a search filter, obtaining as a result, investigations that obtained a Slump Flow of 32.5 cm., For a dose of 0.3% of additive, found in a range of 0.25% to 0.40%. The synthesized comb-shaped additive, with PCE-2 coding, had a compressive strength of 85 MPa with mineral additions, tested at 28 days with an a / c ratio of 0.30. For a PC-3, a compressive strength of 73 MPa was obtained, without mineral additions, tested at 28 days at a ratio a / c = 0.30. The average value of compressive strength, without mineral additions, was 61 MPa, with a w / c ratio between 0.25 to 0.30. It was concluded that the use of plasticizer additives, based on copolymers, has a positive influence on the properties of concrete, reducing water, improving initial and final high strengths, as well as permeability. [ABSTRACT FROM AUTHOR]

Brick from demolitions can be reused as recycled aggregate in the elaboration of concrete, helping to care for the environment by reducing the use of raw materials. The present work aims to achieve a systematic review on the use of crushed bricks in concrete, in order to synthesize the results obtained and discuss the possibility of using this recycled material in different areas of construction. A review of 51 articles indexed between the years 2015 to 2021 was made, distributed as follows: 41 articles are from Scopus and 10 from Sciencedirect, which show how crushed brick influences the properties of concrete. The reviews of the results found that recycled brick aggregates (RBA) generate a deficiency in compressive strength and higher porosity as opposed to natural aggregate (NA). [ABSTRACT FROM AUTHOR]

This article presents an analysis at long ages (≤4 years) of the physical-mechanical properties and durability of concrete hybrids. All of them based on the alkaline activation of Colombian fly ash (FA) with a high content of unburned content (without commercial value). The effect of the type of calcium source was evaluated using 20% additions of Ground-granulated Blast-furnace Slag (GGBFS) and Ordinary Portland Cement (OPC), compared to 100% FA-based concrete. The evaluated properties include compressive strength, splitting tensile strength, absorption, density, porosity, sorptivity, sulfate resistance, acid attack resistance, chloride ion permeability, carbonation susceptibility, and residual resistance at elevated temperatures. The results obtained demonstrate the feasibility of reaching compressive strength values that reach values between 40 and 93 MPa at curing ages of 4 years. In general, the good physical-mechanical and durable performance of the concrete GCV / ESC and GCV / OPC was demonstrated. [ABSTRACT FROM AUTHOR]

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In the last year, the use of self-compacting concrete (SCC) has been increasing since its start due to the capacity it has to fill formwork with a high density of steels, so the use of this type of concrete in the elaboration of reinforced thin walls would be a solution to incomplete filling of this type of prefabricated elements. On the other hand, the use of masonry residue (RM) and recycled coarse concrete aggregate (AGR) from construction and demolition waste (CDW) as a replacement for cement and coarse aggregate respectively would give a sustainable approach to self-compacting concrete. This study aimed to evaluate the influence of CDW on the properties in the fresh state (slump flow, V-funnel, and L-box) and hardened state in cylindrical specimens (compressive strength and splitting tensile strength) and in walls (diagonal tension strength). The mixtures of CAC show that when Portland cement and natural aggregate are replaced by RM and AGR respectively, the concrete can meet the requirements of the European guidelines of the European Federation of National Associations Representing producers and applicators of specialist building products for Concrete (EFNARC). In the hardened state, CACs with CDW achieved acceptable performance compared to the reference mixture (CAC-reference). All mixtures achieved compressive strength greater than 21 MPa suitable for house walls according to (NSR 10). [ABSTRACT FROM AUTHOR]

The function of glue mortars is to integrate masonry in rubble work, however, these elements are constantly affected by injuries derived from humidity, such as efflorescence that causes loss of physical properties like the color, the density and the mass due to the superficial outcrop of salts, internal accumulation of salts and superficial detachments; therefore, in this research, the use of asphalt emulsion as a reducer of this condition was studied. According to the analyzes carried out, it was determined that with additions of 10% and 20% the asphalt emulsion a certain level of water repellency is acquired and with additions of 30% and 40% complete hydrophobicity was achieved. Furthermore, it was determined that the asphalt emulsion reduces efflorescence outcrop by 27% with 10% emulsion, 47% with 20% and 100% for samples with 30% and 40% respectively. Although the use of bituminous additives brings certain advantages over the physical properties of mortars, it inversely reduces mechanical properties such as compressive strength. [ABSTRACT FROM AUTHOR]

Copyright of Cuaderno Activa is the property of Tecnologico de Antioquia, Institucion Universitari and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bistua: Revista de la Facultad de Ciencias Básicas is the property of Facultad de Ciencias Basicas de la Universidad de Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, the influence of the andradite on the mechanical resistance synthesized from the furnace slag converter is evaluated. As activators, 12 M sodium hydroxide and 5 M sodium silicate were used. Sodium hydroxide remained constant at 5% and at 15% in sodium silicate. Ceramic material was added in proportions of 5%, 10%, 15% and 20%. The curing of the paste was done at room temperature for 24 hours. The particle size of the white slag and the ceramic material was 150 Î?m. XDR and MEB were used to analyze the possible mechanisms of formation of andradite and calcium carbonate. Samples were failed in the universal testing machine. The influence of the chemical compounds formed on the compressive strength was determined. The results indicate that the proposed conditions are suitable for the formation of crystalline structures characteristic of geopolymeric materials. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)