The fundamental natural period of oscillation is a critical parameter in evaluating the design base shear of buildings. Worldwide seismic design codes typically employ height-based empirical formulas to estimate this period for various building categories, without distinguishing between regular and irregular buildings. This study proposes a formula specifically for reinforced concrete (RC) moment-resisting frame (MRF) buildings with dominant re-entrant corner type plan irregularity. A total of 190 re-entrant corner dominant building models with different shapes (C-, L-, T-, and PLUS-type), heights, and floor configurations were prepared, and eigenvalue analysis (EVA) was conducted. The fundamental natural period of oscillation for each model was evaluated and compared with the height-based formulas from seismic design codes and the period–height relationship proposed in existing literature. A nonlinear regression model, using a multi-variable power function, is proposed to estimate the fundamental natural period for these re-entrant corner dominant building models. This model considers the A/L ratio in both directions of the building, along with its height. Both unconstrained and constrained regression analyses were performed to derive a formula that best fits the fundamental natural period data. The study recommends that the unconstrained best-fit minus one standard deviation curve can conservatively define the fundamental natural period of oscillation for re-entrant corner dominant RC building models. The equation defining this curve has the potential to replace the existing seismic design code-based period-height formula.
{"title":"Fundamental period equations for plan irregular moment-resisting frame buildings","authors":"J. Suthar, Sharadkumar Purohit","doi":"10.13167/2024.28.2","DOIUrl":"https://doi.org/10.13167/2024.28.2","url":null,"abstract":"The fundamental natural period of oscillation is a critical parameter in evaluating the design base shear of buildings. Worldwide seismic design codes typically employ height-based empirical formulas to estimate this period for various building categories, without distinguishing between regular and irregular buildings. This study proposes a formula specifically for reinforced concrete (RC) moment-resisting frame (MRF) buildings with dominant re-entrant corner type plan irregularity. A total of 190 re-entrant corner dominant building models with different shapes (C-, L-, T-, and PLUS-type), heights, and floor configurations were prepared, and eigenvalue analysis (EVA) was conducted. The fundamental natural period of oscillation for each model was evaluated and compared with the height-based formulas from seismic design codes and the period–height relationship proposed in existing literature. A nonlinear regression model, using a multi-variable power function, is proposed to estimate the fundamental natural period for these re-entrant corner dominant building models. This model considers the A/L ratio in both directions of the building, along with its height. Both unconstrained and constrained regression analyses were performed to derive a formula that best fits the fundamental natural period data. The study recommends that the unconstrained best-fit minus one standard deviation curve can conservatively define the fundamental natural period of oscillation for re-entrant corner dominant RC building models. The equation defining this curve has the potential to replace the existing seismic design code-based period-height formula.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140422080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sandra Juradin, Bruno Bartulović, Dujmo Žižić, S. Mrakovčić
Cement screed consists of cement, sharp sand and water, laid as a thin layer over the concrete subfloor. Although the screed is strong, it can be additionally reinforced with fibres, most often polypropylene fibres. In this study, cotton knitted fabric waste (CKFW) was obtained from a local factory producing underwear to reinforce the cement screed. A total of eight mixtures were made: reference mixture, screed reinforced with polypropylene fibres and six mixtures reinforced with CKFW. CKFW was added in 1,25 %, 2,50 % and 5,00 % of the total volume. Before adding to the mixtures, the first CKFW group was saturated with tap water, whereas, the second CKFW group was saturated with dispersion that improves adhesion. The density and air content of the fresh mixtures were tested, and the compressive strength and flexural strength were determined when the specimens were 28 days old. The specific fracture energy is determined based on the curve from the plot of load vs. displacement. The CKFW increases the ductility of cement screeds, although it has no significant effect on the compressive and flexural strength of the specimens. The CKFW that was saturated with tap water achieved better results.
{"title":"Cotton knitted fabric waste as reinforcement in cement screed","authors":"Sandra Juradin, Bruno Bartulović, Dujmo Žižić, S. Mrakovčić","doi":"10.13167/2024.28.1","DOIUrl":"https://doi.org/10.13167/2024.28.1","url":null,"abstract":"Cement screed consists of cement, sharp sand and water, laid as a thin layer over the concrete subfloor. Although the screed is strong, it can be additionally reinforced with fibres, most often polypropylene fibres. In this study, cotton knitted fabric waste (CKFW) was obtained from a local factory producing underwear to reinforce the cement screed. A total of eight mixtures were made: reference mixture, screed reinforced with polypropylene fibres and six mixtures reinforced with CKFW. CKFW was added in 1,25 %, 2,50 % and 5,00 % of the total volume. Before adding to the mixtures, the first CKFW group was saturated with tap water, whereas, the second CKFW group was saturated with dispersion that improves adhesion. The density and air content of the fresh mixtures were tested, and the compressive strength and flexural strength were determined when the specimens were 28 days old. The specific fracture energy is determined based on the curve from the plot of load vs. displacement. The CKFW increases the ductility of cement screeds, although it has no significant effect on the compressive and flexural strength of the specimens. The CKFW that was saturated with tap water achieved better results.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140450032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Saran Sathish Kumar, Amudhan Vijayakumar, Daniel Cruze, Hemnath Kasaram
This article presents a novel magnetic pole repulsive damper (MPRD) incorporating neodymium magnetic repulsive blocks and springs. The study explores the mechanical properties of the springs and magnetic blocks through numerical simulations using ANSYS and experimental evaluation. To gain deeper insights into the behaviour of the MPRD, an accurate and high-fidelity finite element model was developed. The evaluation process involved a comprehensive comparison between the numerical simulations and experimental tests, explicitly focusing on cyclic compression–tension forces. The study encompassed the functioning, design implications, fabrication technique, mechanical performance, and numerical simulation for the cyclic compression–tension forces of the MPRD. The cyclic compression–tension tests revealed a gradual increase in force, with the MPRD achieving an ultimate force of 2,877 kN. The MPRD exhibited robust hysteresis behaviour in cyclic loading, showing its capacity to undergo and uphold the stability of the combination of its materials. The cyclic compression–tension results indicated the maximum force carrying capability of the damper. This resilience implies its full reusability in such scenarios. The comparison between cyclic compression–tension tests confirmed the alignment between the numerical simulation and experimental investigation.
{"title":"EXPERIMENTAL AND NUMERICAL SIMULATION OF A NOVEL MAGNETIC POLE REPULSIVE PASSIVE DAMPER FOR VIBRATION CONTROL","authors":"Saran Sathish Kumar, Amudhan Vijayakumar, Daniel Cruze, Hemnath Kasaram","doi":"10.13167/2023.27.8","DOIUrl":"https://doi.org/10.13167/2023.27.8","url":null,"abstract":"This article presents a novel magnetic pole repulsive damper (MPRD) incorporating neodymium magnetic repulsive blocks and springs. The study explores the mechanical properties of the springs and magnetic blocks through numerical simulations using ANSYS and experimental evaluation. To gain deeper insights into the behaviour of the MPRD, an accurate and high-fidelity finite element model was developed. The evaluation process involved a comprehensive comparison between the numerical simulations and experimental tests, explicitly focusing on cyclic compression–tension forces. The study encompassed the functioning, design implications, fabrication technique, mechanical performance, and numerical simulation for the cyclic compression–tension forces of the MPRD. The cyclic compression–tension tests revealed a gradual increase in force, with the MPRD achieving an ultimate force of 2,877 kN. The MPRD exhibited robust hysteresis behaviour in cyclic loading, showing its capacity to undergo and uphold the stability of the combination of its materials. The cyclic compression–tension results indicated the maximum force carrying capability of the damper. This resilience implies its full reusability in such scenarios. The comparison between cyclic compression–tension tests confirmed the alignment between the numerical simulation and experimental investigation.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136312117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hemnath Kasaram, Amudhan Vijayakumar, Daniel Cruze, Saran Sathish Kumar
Owing to its high energy dissipation characteristics, the passive damper is an effective means of mitigating natural hazards for structures. In this study, a novel magnetic pole repulsive damper (MPRD), designed for reducing structural responses during natural hazards such as earthquakes, was developed and its performance was validated. The MPRD is an effective solution for seismic protection that works on the principle of magnetic repulsion and has a higher energy dissipation capacity than conventional dampers. The MPRD was fabricated using mild steel, neodymium magnets, and a set of helical springs. Two scaled reinforced concrete frames were tested using a 50 kN loading actuator. One frame was equipped with the MPRD, while the other served as a conventional frame for comparison. The frame with the MPRD showed reduced displacements. Compared with the conventional frame, that with the MPRD exhibited an increase in load of 40 % and an increase in energy dissipation of 6,44 %. Further, an increase in lateral stiffness, a 19,23 % increase in stiffness degradation, and changes in crack patterns were observed in the frame with MPRD compared to the conventional frame. The study's success in validating the MPRD performance in reducing structural responses in moderate to high seismicity regions makes it a promising solution for building seismic protection.
{"title":"MAGNETIC POLE REPULSIVE DAMPER (MPRD): A PROMISING SOLUTION FOR SEISMIC PROTECTION OF STRUCTURES","authors":"Hemnath Kasaram, Amudhan Vijayakumar, Daniel Cruze, Saran Sathish Kumar","doi":"10.13167/2023.27.7","DOIUrl":"https://doi.org/10.13167/2023.27.7","url":null,"abstract":"Owing to its high energy dissipation characteristics, the passive damper is an effective means of mitigating natural hazards for structures. In this study, a novel magnetic pole repulsive damper (MPRD), designed for reducing structural responses during natural hazards such as earthquakes, was developed and its performance was validated. The MPRD is an effective solution for seismic protection that works on the principle of magnetic repulsion and has a higher energy dissipation capacity than conventional dampers. The MPRD was fabricated using mild steel, neodymium magnets, and a set of helical springs. Two scaled reinforced concrete frames were tested using a 50 kN loading actuator. One frame was equipped with the MPRD, while the other served as a conventional frame for comparison. The frame with the MPRD showed reduced displacements. Compared with the conventional frame, that with the MPRD exhibited an increase in load of 40 % and an increase in energy dissipation of 6,44 %. Further, an increase in lateral stiffness, a 19,23 % increase in stiffness degradation, and changes in crack patterns were observed in the frame with MPRD compared to the conventional frame. The study's success in validating the MPRD performance in reducing structural responses in moderate to high seismicity regions makes it a promising solution for building seismic protection.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134905651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Subhakanta Dash, Piyush Gupta, Syed Mohammed Mustakim, Itishree Mohanty
In this paper, two types of lightweight fly ash (FA) aggregates: cold bonded fly ash (CFA) and sintered fly ash (SFA) aggregates were prepared through the cold bonding and sintering method. During the pelletization process, different ratios of binders to fly ash were used, i.e., 10:90, 15:85, 17:83, and 20:80 with a set amount of water. Cement, metakaolin, sodium silicate, urea-formaldehyde resin, bentonite powder, and phenol-formaldehyde resin were employed as binders. A comparative study on physicochemical, mechanical, phase identification, microstructure, and optical analysis of CFA and SFA was performed. The results showed that CFA (an alkali binder) had a higher water absorption (WA) value of 9,50 % with a crushing strength (CS) value of 6,30 MPa than SFA (sodium silicate binder) with a CS value of 5,80 MPa and a WA value of 10,28 %. Experimental observations also demonstrated that the leaching ability of SFA was considerably lower than that of CFA. Most notably, SFA can be used as a substitute for construction material and structural applications along with solving FA waste disposal and related problems to a considerable extent.
{"title":"INFLUENCE OF BINDERS, MIX PROPORTIONS, AND FABRICATION METHOD ON THE CHARACTERISTICS OF FLY ASH AGGREGATE","authors":"Subhakanta Dash, Piyush Gupta, Syed Mohammed Mustakim, Itishree Mohanty","doi":"10.13167/2023.27.5","DOIUrl":"https://doi.org/10.13167/2023.27.5","url":null,"abstract":"In this paper, two types of lightweight fly ash (FA) aggregates: cold bonded fly ash (CFA) and sintered fly ash (SFA) aggregates were prepared through the cold bonding and sintering method. During the pelletization process, different ratios of binders to fly ash were used, i.e., 10:90, 15:85, 17:83, and 20:80 with a set amount of water. Cement, metakaolin, sodium silicate, urea-formaldehyde resin, bentonite powder, and phenol-formaldehyde resin were employed as binders. A comparative study on physicochemical, mechanical, phase identification, microstructure, and optical analysis of CFA and SFA was performed. The results showed that CFA (an alkali binder) had a higher water absorption (WA) value of 9,50 % with a crushing strength (CS) value of 6,30 MPa than SFA (sodium silicate binder) with a CS value of 5,80 MPa and a WA value of 10,28 %. Experimental observations also demonstrated that the leaching ability of SFA was considerably lower than that of CFA. Most notably, SFA can be used as a substitute for construction material and structural applications along with solving FA waste disposal and related problems to a considerable extent.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135883890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study examined the influence of partial sand replacement with iron filings on the mechanical and physical characteristics of concrete, as well as conducted experimental tests of the shear behaviour of reinforced-concrete beams. Four replacement rates were used in this study, i.e., 5 %, 10 %, 20 %, and 30 % with a reference mixture containing no iron filings. At ages 7, 14, and 28 days, mechanical property tests (slump, density, ultrasonic pulse velocity, compressive strength, and splitting strength tests) were conducted. In addition, the shear behaviour of five reinforced-concrete beams with the same replacement rates (0 %, 5 %, 10 %, 20 %, and 30 %) were experimentally tested. Tests were conducted to determine the ultimate load failure, final deflection, energy absorption, stiffness, ductility index, compressive stress, and crack formations. According to the results, the correlation between the slump test and iron filings is positive; however, that for absorption is negative. With a higher percentage of iron-filing replacement, the density and ultrasonic pulse velocity increased. For specimens with 30,00 % iron filings, the densities, pulse velocities, and slumps were raised by 6,27 %, 2,44 %, and 58,33 %, respectively, compared to the reference specimens, whereas the absorption rate decreased by 20,00 %. Having 20,00 % iron filings produced the maximum compressive and splitting strengths of 28,00 %, which was 4,60 % higher than the reference mixture, whereas 30,00 % iron filings produced the highest flexural strength, which was 9,50 % higher than the reference mix. The findings of beam testing revealed that increasing the iron-filing content in concrete beams increased the final failure load, final deflection, ductility index, and energy absorption by 6,70 %, 10,29 %, 11,30 %, and 35,00 %, respectively. The initial and secant stiffnesses decreased at rates of 12,60 % and 3,10 %, respectively.
{"title":"SHEAR BEHAVIOUR OF REINFORCED-CONCRETE BEAMS INCORPORATING IRON FILINGS AS SAND REPLACEMENT","authors":"Abbas Dawood, Hayder Al-Khazraji, Dua'a Mahmood","doi":"10.13167/2023.27.6","DOIUrl":"https://doi.org/10.13167/2023.27.6","url":null,"abstract":"This study examined the influence of partial sand replacement with iron filings on the mechanical and physical characteristics of concrete, as well as conducted experimental tests of the shear behaviour of reinforced-concrete beams. Four replacement rates were used in this study, i.e., 5 %, 10 %, 20 %, and 30 % with a reference mixture containing no iron filings. At ages 7, 14, and 28 days, mechanical property tests (slump, density, ultrasonic pulse velocity, compressive strength, and splitting strength tests) were conducted. In addition, the shear behaviour of five reinforced-concrete beams with the same replacement rates (0 %, 5 %, 10 %, 20 %, and 30 %) were experimentally tested. Tests were conducted to determine the ultimate load failure, final deflection, energy absorption, stiffness, ductility index, compressive stress, and crack formations. According to the results, the correlation between the slump test and iron filings is positive; however, that for absorption is negative. With a higher percentage of iron-filing replacement, the density and ultrasonic pulse velocity increased. For specimens with 30,00 % iron filings, the densities, pulse velocities, and slumps were raised by 6,27 %, 2,44 %, and 58,33 %, respectively, compared to the reference specimens, whereas the absorption rate decreased by 20,00 %. Having 20,00 % iron filings produced the maximum compressive and splitting strengths of 28,00 %, which was 4,60 % higher than the reference mixture, whereas 30,00 % iron filings produced the highest flexural strength, which was 9,50 % higher than the reference mix. The findings of beam testing revealed that increasing the iron-filing content in concrete beams increased the final failure load, final deflection, ductility index, and energy absorption by 6,70 %, 10,29 %, 11,30 %, and 35,00 %, respectively. The initial and secant stiffnesses decreased at rates of 12,60 % and 3,10 %, respectively.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135883886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The mining industry produces vast quantities of mine refuse, including waste rock and tailings, which pose a significant environmental problem. Mining residues, which are generated during ore extraction and mineral processing, are typically deposited near mines. This method of mine waste disposal can lead to environmental problems and land loss. This fact has prompted research into the utilisation of sediments as alternative materials to produce backfill and paving materials. The Democratic Republic of the Congo (DRC) possesses approximately 80 % of Africa’s coltan reserves, which is geologically unsustainable considering its many mineral resources. When coltan is extracted, geologically heterogeneous debris spanning from fine particles to boulders is produced. The purpose of this study was to analyse the potential value of mine tailings in road embankments using coltan waste rock from the eastern DRC as a case study, in accordance with the French standard. To accomplish this, it was necessary to evaluate the coltan waste rock’s chemical, mineralogical, and geotechnical properties. The coltan mining waste rock studied (SS1,i, SS2,i, and SS3,i) were found to be naturally clayey in nature, with characteristics for use in road construction. However, stabilised at 60 % by the SS4, classified as sand according to the Laboratoire Central des Ponts et Chaussées (LCPC) classification, the SS1,i, SS2,i, and SS3,i clayey waste rock possess the necessary characteristics for sub-base course materials.
采矿业产生了大量的矿渣，包括废石和尾矿，造成了严重的环境问题。采矿残留物是在矿石提取和矿物加工过程中产生的，通常沉积在矿山附近。这种矿山废弃物处理方法会导致环境问题和土地流失。这一事实促使人们研究利用沉积物作为替代材料来生产回填和铺路材料。刚果民主共和国(DRC)拥有非洲约80%的钶钽铁矿储量，考虑到其众多矿产资源，这在地质上是不可持续的。当提取钶钽铁矿时，会产生从细颗粒到巨石不等的地质不均匀碎屑。本研究的目的是根据法国标准，以刚果民主共和国东部的钶钽铁矿废石为例，分析矿山尾矿在道路路堤中的潜在价值。为了实现这一目标，有必要评估钶钽铁矿废石的化学、矿物学和岩土力学性质。所研究的钶钽铁矿废石(SS1,i, SS2,i和SS3,i)在性质上是天然粘土，具有用于道路建设的特性。然而，SS4稳定在60%，根据laboratory Central des Ponts et chauss (LCPC)分类归类为砂，SS1、i、SS2、i和SS3、i粘土废石具有亚基层材料的必要特征。
{"title":"POTENTIAL USE OF COLTAN MINING WASTE ROCK IN ROAD CONSTRUCTION","authors":"Alinabiwe Nyamuhanga Ally, Manjia Marcelline Blanche, Masika Muhiwa Grâce, Elodie Rufine Zang, Ngapgue François, Chrispin Pettang","doi":"10.13167/2023.27.2","DOIUrl":"https://doi.org/10.13167/2023.27.2","url":null,"abstract":"The mining industry produces vast quantities of mine refuse, including waste rock and tailings, which pose a significant environmental problem. Mining residues, which are generated during ore extraction and mineral processing, are typically deposited near mines. This method of mine waste disposal can lead to environmental problems and land loss. This fact has prompted research into the utilisation of sediments as alternative materials to produce backfill and paving materials. The Democratic Republic of the Congo (DRC) possesses approximately 80 % of Africa’s coltan reserves, which is geologically unsustainable considering its many mineral resources. When coltan is extracted, geologically heterogeneous debris spanning from fine particles to boulders is produced. The purpose of this study was to analyse the potential value of mine tailings in road embankments using coltan waste rock from the eastern DRC as a case study, in accordance with the French standard. To accomplish this, it was necessary to evaluate the coltan waste rock’s chemical, mineralogical, and geotechnical properties. The coltan mining waste rock studied (SS1,i, SS2,i, and SS3,i) were found to be naturally clayey in nature, with characteristics for use in road construction. However, stabilised at 60 % by the SS4, classified as sand according to the Laboratoire Central des Ponts et Chaussées (LCPC) classification, the SS1,i, SS2,i, and SS3,i clayey waste rock possess the necessary characteristics for sub-base course materials.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136238685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, calcium carbonate was formed on the surfaces and inner structure of concrete using the microbially induced carbonate precipitation method. Bacillus megaterium bacteria were supplemented into the curing water and concrete mixtures. Three types of concrete were tested: control concrete, bacteria-containing concrete, and concrete cured in bacterial liquid. Compressive strength, water absorption, capillary water absorption, scanning electron microscopy (SEM), and mapping analyses were conducted to investigate the effects of bacterial additive or bacterial curing to concrete specimens. Bacteria spore added to the concrete mixture and curing in bacterial media increased the compressive strengths of concrete by up to 9,52 % at the end of 28 days of curing. Bacterial curing and the addition of bacteria spores caused a reduction in water absorption rates owing to changes in the concrete structures. Calcite only formed on the surfaces of the samples treated with bacterial curing liquid, thereby limiting its effect on capillary water absorption. In contrast, capillary water absorption in the bacterial concrete decreased by 50 % compared to the control concrete. The crystalline structures of calcium carbonate and bacterial concrete were analysed through SEM imaging. Mapping analysis revealed that the primary elements of calcite were considerably more concentrated on the surface of bacterial concrete than in the control concrete.
{"title":"EFFECT OF BACTERIAL CURING AND BACTERIAL ADDITIVE ON CONCRETE PROPERTIES","authors":"Musa Yıldırım, Hacer Bilir Özhan","doi":"10.13167/2023.27.3","DOIUrl":"https://doi.org/10.13167/2023.27.3","url":null,"abstract":"In this study, calcium carbonate was formed on the surfaces and inner structure of concrete using the microbially induced carbonate precipitation method. Bacillus megaterium bacteria were supplemented into the curing water and concrete mixtures. Three types of concrete were tested: control concrete, bacteria-containing concrete, and concrete cured in bacterial liquid. Compressive strength, water absorption, capillary water absorption, scanning electron microscopy (SEM), and mapping analyses were conducted to investigate the effects of bacterial additive or bacterial curing to concrete specimens. Bacteria spore added to the concrete mixture and curing in bacterial media increased the compressive strengths of concrete by up to 9,52 % at the end of 28 days of curing. Bacterial curing and the addition of bacteria spores caused a reduction in water absorption rates owing to changes in the concrete structures. Calcite only formed on the surfaces of the samples treated with bacterial curing liquid, thereby limiting its effect on capillary water absorption. In contrast, capillary water absorption in the bacterial concrete decreased by 50 % compared to the control concrete. The crystalline structures of calcium carbonate and bacterial concrete were analysed through SEM imaging. Mapping analysis revealed that the primary elements of calcite were considerably more concentrated on the surface of bacterial concrete than in the control concrete.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136238671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. A. S. Aslam, Sadaf Noshin, Khurram Riaz, A. Rehman, Farooq Mustafa Joyiaa, Muhammad Adnan, H. M. U. Aslam, Abrar Ahmad, Mazhar Yasin, A. Hamza, Shabeer Hussain
The use of beverage containers, most of which are made of polyethylene terephthalate bottles, results in several problems with regard to sustainability. The purpose of this study was to evaluate and contrast the impact on the mechanical characteristics of concrete caused by the incorporation of polyethylene terephthalate bottle fibres in varying amounts. These fibres were generated by cutting bottles into precise dimensions (width of 5 mm and length of 25 mm), and they were used in various concentrations such as 0,25 %; 0,5 % and 1,0 % by volume of concrete with different amounts of recycled aggregate. To verify the reliability of the outcomes of the experiment, a statistical analysis was performed. According to the results, the concrete that contained 0 % recycled coarse aggregate and varying amounts of plastic fibres had a greater degree of workability compared with concrete that had either 50 % or 100 % recycled coarse aggregate. The comprehensive test findings demonstrated that the addition of polyethylene terephthalate fibres decreased compressive and split tensile strength. The study concluded that certain parameters, such as plastic fibres, curing days, and recycled aggregate, interacted together in a synergistic manner to impact the compressive and splitting tensile strengths of the concrete, with proposed equations for their prediction.
{"title":"EFFECT OF WASTE POLYETHYLENE TEREPHTHALATE BOTTLE FIBERS ON THE MECHANICAL PROPERTIES OF RECYCLED CONCRETE","authors":"H. A. S. Aslam, Sadaf Noshin, Khurram Riaz, A. Rehman, Farooq Mustafa Joyiaa, Muhammad Adnan, H. M. U. Aslam, Abrar Ahmad, Mazhar Yasin, A. Hamza, Shabeer Hussain","doi":"10.13167/2023.27.1","DOIUrl":"https://doi.org/10.13167/2023.27.1","url":null,"abstract":"The use of beverage containers, most of which are made of polyethylene terephthalate bottles, results in several problems with regard to sustainability. The purpose of this study was to evaluate and contrast the impact on the mechanical characteristics of concrete caused by the incorporation of polyethylene terephthalate bottle fibres in varying amounts. These fibres were generated by cutting bottles into precise dimensions (width of 5 mm and length of 25 mm), and they were used in various concentrations such as 0,25 %; 0,5 % and 1,0 % by volume of concrete with different amounts of recycled aggregate. To verify the reliability of the outcomes of the experiment, a statistical analysis was performed. According to the results, the concrete that contained 0 % recycled coarse aggregate and varying amounts of plastic fibres had a greater degree of workability compared with concrete that had either 50 % or 100 % recycled coarse aggregate. The comprehensive test findings demonstrated that the addition of polyethylene terephthalate fibres decreased compressive and split tensile strength. The study concluded that certain parameters, such as plastic fibres, curing days, and recycled aggregate, interacted together in a synergistic manner to impact the compressive and splitting tensile strengths of the concrete, with proposed equations for their prediction.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80065986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study presents a meticulous investigation into the catastrophic landslide that impacted Malin village in Pune district of Maharashtra, India. By employing a multi-faceted approach encompassing field, laboratory, and numerical analyses, in the study, stability governing parameters were thoroughly assessed with respect to varying levels of water saturation. Field investigation provided crucial insights into the geographical profile, field density, slope strata, and representative soil sample acquired from hill slopes. Furthermore, extensive laboratory investigations were conducted to gain a comprehensive understanding of the role of stability governing parameters under different water saturation levels. The limit equilibrium method was employed for numerical simulation to rigorously evaluate slope stability. The results revealed the significant influence of increased water saturation on stability governing parameters, leading to slope instability, which was confirmed by numerical simulation. The study further established that excessive rainfall triggered the landslide, saturating the soil mass and deteriorating the stability governing parameters, ultimately leading to instability. The findings of this study offer valuable insights for mitigating landslides and can be instrumental in developing effective monitoring and warning systems.
{"title":"EFFECT OF WATER SATURATION ON STABILITY OF A HILL SLOPE: MALIN CASE STUDY","authors":"Prashant Sudani, K. Patil","doi":"10.13167/2023.26.9","DOIUrl":"https://doi.org/10.13167/2023.26.9","url":null,"abstract":"The study presents a meticulous investigation into the catastrophic landslide that impacted Malin village in Pune district of Maharashtra, India. By employing a multi-faceted approach encompassing field, laboratory, and numerical analyses, in the study, stability governing parameters were thoroughly assessed with respect to varying levels of water saturation. Field investigation provided crucial insights into the geographical profile, field density, slope strata, and representative soil sample acquired from hill slopes. Furthermore, extensive laboratory investigations were conducted to gain a comprehensive understanding of the role of stability governing parameters under different water saturation levels. The limit equilibrium method was employed for numerical simulation to rigorously evaluate slope stability. The results revealed the significant influence of increased water saturation on stability governing parameters, leading to slope instability, which was confirmed by numerical simulation. The study further established that excessive rainfall triggered the landslide, saturating the soil mass and deteriorating the stability governing parameters, ultimately leading to instability. The findings of this study offer valuable insights for mitigating landslides and can be instrumental in developing effective monitoring and warning systems.","PeriodicalId":29665,"journal":{"name":"Advances in Civil and Architectural Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73699022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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