Mechanical Properties and Flexural Strength of Reinforced Concrete Beams Containing Waste Material as Partial Replacement for Coarse Aggregates

Parween Latif Aziz,Mohammed R. Abdulkadir 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.1

The volume of waste materials and by products are increasing and endangering the environment safety. Some of these waste materials can be used in the production of building materials, such as concrete. In order to study the possibility of using some waste materials as aggregate replacement for the purpose of producing structural RC members this investigation was carried out. This research describes the results of test of reinforced concrete beams containing different types of waste materials, namely crumbed rubber, granular plastic, and crushed bricks. Ten RC beams containing different percentages (0%, 5%, 10%, and 15%) of waste materials as coarse aggregate replacement have been investigated. The beams were 150 × 200 mm in size and 2000 mm in length and tested under four points loading. Mechanical properties of the concrete used for the beams were also studied. Test results indicated a reduction in compressive strength, splitting tensile strength, and elastic modulus due to the inclusion of the waste materials used. The maximum loss in concrete compressive strength was recorded to be 54.95%, 50.31%, and 20.41% for concrete mix with 15% crumbed rubber, plastic waste aggregate, and 5% crushed brick, respectively. Test results of the beams showed that ultimate load capacity was reduced by 30.21% and 9.94% when 15% of crumbed rubber and granular plastic were used, respectively. The failure mode of all the tested beams was similar and followed same pattern, steel yielding followed by concrete compression failure. Finally, based on the flexural capacity of the beams tested it is recommend that gravel replacement of up to 15% of crumbed rubber, granular plastic, and crushed brick can be safely used to produce normal type of RC beams for minor structural application.

Methods for evaluating effects of unloader knee braces on joint health: a review

Rizuwana Parween,Duraisamy Shriram,Rajesh Elara Mohan,Yee Han Dave Lee,Karupppasamy Subburaj 대한의용생체공학회 2019 Biomedical Engineering Letters (BMEL) Vol.9 No.2

The paper aims to provide a state-of-the-art review of methods for evaluating the eff ectiveness and eff ect of unloaderknee braces on the knee joint and discuss their limitations and future directions. Unloader braces are prescribed as a nonpharmacologicalconservative treatment option for patients with medial knee osteoarthritis to provide relief in terms of painreduction, returning to regular physical activities, and enhancing the quality of life. Methods used to evaluate and monitorthe eff ectiveness of these devices on patients’ health are categorized into three broad categories (perception-, biochemical-,and morphology-based), depending upon the process and tools used. The main focus of these methods is on the short-termclinical outcome (pain or unloading effi ciency). There is a signifi cant technical, research, and clinical literature gap in understandingthe short- and long-term consequences of these braces on the tissues in the knee joint, including the cartilage andligaments. Future research directions may complement existing methods with advanced quantitative imaging (morphological,biochemical, and molecular) and numerical simulation are discussed as they off er potential in assessing long-term andpost-bracing eff ects on the knee joint.

An Analytical Hierarchy Process Approach for Prioritization of Objectives and Parameters for an Integrated Urban Water Management

Shama Parween,Rajan Chandra Sinha 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.4

For sustainable development of urban areas, it is essential to address urban water management integrated with the urban water systems and spatial planning of the cities and the subsequent uncertainties. An integrated urban water management and planning model will help ensure water security, mitigate floods and droughts, reduce the negative environmental impact of urbanization and climate change, and bring coherence in the water supply management with the cities’ spatial planning and relevant policies. In the present research, the Analytical Hierarchy Process (AHP), a multi-criteria decision analysis, has been implemented to calculate the weightage of different parameters associated with urban water management and planning. AHP uses linguistic and quantitative variables based on experts' opinions for selecting and prioritizing the objectives and parameters for an integrated approach to urban water management and spatial planning under uncertainties. The local and global weights of objectives, parameters, key indicators, and sub-indicators were calculated after pairwise comparison by 32 experts from academia and industry in urban planning and civil and environmental engineering for the case of Ranchi, a city in eastern India. The study establishes the financial factors (36.97%) as one of the important attributes, followed by environmental factors (26.71%) for consideration in integrated urban water management. Further, Alternative D (45.256%) is framed by collaborating different objectives of IUWM, such as ensuring water security through alternative water sources, mitigating floods and droughts, and water supply planning considering land use, management policies, and climate change. The research findings can assist decision-makers in prioritizing the various objectives and parameters for integrated urban water management in cities with similar population sizes and organic growth.

Potential hydrometallurgical processes to recycle metals from discarded personal computer

Dinkar Om Shankar,Parween Rukshana,Panda Rekha,Choubey Pankaj Kumar,Ambade Balram,Jha Manis Kumar 한국자원공학회 2022 Geosystem engineering Vol.25 No.3

Rapid technological modernization has accelerated the replacement of older electronic goods with newer ones, which has led to the generation of huge quantities of discarded electronic items at its end-of-life, known as electronic wastes (e-wastes). The growing quantity of e-wastes has become a major threat to the society as well as environment. On the other hand, e-wastes contain several valuable metals and materials of high economic value, which compels researchers to work in the area for secondary resources for metal recovery. Metal recovery from such secondary resources will not only preserve the primary resources but also reduce the loss of valuable metals/materials, protect the environment from their hazardous effects as well as reduce the demand-supply gap of metals up to some extent. In view of the above, present study is focused on the possible effort to figure out variety of metals present in the component of waste personal computers (WPCs) as well as different recycling processes implemented for the efficient recovery of metals.

Maximal chain of ideals and $n$-maximal ideal

Hemin A. Ahmad,Parween A. Hummadi 대한수학회 2023 대한수학회논문집 Vol.38 No.2

In this paper, the concept of a maximal chain of ideals is introduced. Some properties of such chains are studied. We introduce some other concepts related to a maximal chain of ideals such as the $n$-maximal ideal, the maximal dimension of a ring $S$ $(M.\dim(S))$, the maximal depth of an ideal $K$ of $S$ $(M.d(K))$ and maximal height of an ideal $K(M.d(K))$.

Influence of loose bonding, initial stress and reinforcement on Love-type wave propagating in a functionally graded piezoelectric composite structure

Abhishek K. Singh,Zeenat Parween,Mriganka S. Chaki,Shruti Mahto 국제구조공학회 2018 Smart Structures and Systems, An International Jou Vol.22 No.3

This present study investigates Love-type wave propagation in composite structure consists of a loosely bonded functionally graded piezoelectric material (FGPM) stratum lying over a functionally graded initially-stressed fibre-reinforced material (FGIFM) substrate. The closed-form expressions of the dispersion relation have been obtained analytically for both the cases of electrically open and electrically short conditions. Some special cases of the problem have also been studied and the obtained results are found in well-agreement with the classical Love wave equation. The emphatic influence of wave number, bonding parameter associated with bonding of stratum with substrate of the composite structure, piezoelectric coefficient as well as dielectric constant of the piezoelectric stratum, horizontal initial stresses, and functional gradedness of the composite structure on the phase velocity of Love-type wave has been reported and illustrated through numerical computation along with graphical demonstration in both the cases of electrically open and electrically short condition for the reinforced and reinforced-free composite structure. Comparative study has been carried out to analyze the distinct cases associated with functional gradedness of the composite structure and also various cases which reveals the influence of piezoelectricity, reinforcement and horizontal initial stress acting in the composite structure, and bonding of the stratum and substrate of the composite structure in context of the present problem which serves as one of the major highlights of the study.

Influence of loose bonding, initial stress and reinforcement on Love-type wave propagating in a functionally graded piezoelectric composite structure

Singh, Abhishek K.,Parween, Zeenat,Chaki, Mriganka S.,Mahto, Shruti Techno-Press 2018 Smart Structures and Systems, An International Jou Vol.22 No.3

This present study investigates Love-type wave propagation in composite structure consists of a loosely bonded functionally graded piezoelectric material (FGPM) stratum lying over a functionally graded initially-stressed fibre-reinforced material (FGIFM) substrate. The closed-form expressions of the dispersion relation have been obtained analytically for both the cases of electrically open and electrically short conditions. Some special cases of the problem have also been studied and the obtained results are found in well-agreement with the classical Love wave equation. The emphatic influence of wave number, bonding parameter associated with bonding of stratum with substrate of the composite structure, piezoelectric coefficient as well as dielectric constant of the piezoelectric stratum, horizontal initial stresses, and functional gradedness of the composite structure on the phase velocity of Love-type wave has been reported and illustrated through numerical computation along with graphical demonstration in both the cases of electrically open and electrically short condition for the reinforced and reinforced-free composite structure. Comparative study has been carried out to analyze the distinct cases associated with functional gradedness of the composite structure and also various cases which reveals the influence of piezoelectricity, reinforcement and horizontal initial stress acting in the composite structure, and bonding of the stratum and substrate of the composite structure in context of the present problem which serves as one of the major highlights of the study.

Treatment of industrial effluent to reclaim copper using adsorption technique

Bawkar Shilpa Kalamani,Choubey Pankaj Kumar,Parween Rukshana,Panda Rekha,Singh Pramod Kumar,Jha Manis Kumar,Lee Jae-chun 한국자원공학회 2022 Geosystem engineering Vol.25 No.4

Effluent generated during metal finishing in industries contains large amount of heavy metals, which get discharged into water bodies and creates environmental pollution as well as loss of metal values. Present studies report the adsorption of copper (Cu) from the effluent using Tulsion T-42 resin. Experiments were carried out for the adsorption of Cu from the effluent of Chemical and Mechanical Polishing (CMP) industries using cationic resin Tulsion T-42 (adsorbent). To get the optimized adsorption condition for copper the studies were carried out with varying process parameters i.e., contact time, adsorbent dose, pH, etc. Result of the batch experiments shows that 95% copper was adsorbed from the effluent containing 100 ppm copper using 0.1 g Tulsion T-42 in 50 mL feed solution at pH 4.0 in contact time of 30 min. The obtained data from Cu adsorption studies fitted well with Freundlich adsorption isotherm and followed second-order rate reaction. The 99% copper was found to be eluted from loaded adsorbent using 10% sulfuric acid in 60 min contact time. FT-IR result confirmed that complex with active sulphonic group of Tulsion T-42 was formed. The findings of the studies will be useful for the reclamation of copper from the waste water of metal finishing industries.

구리 회수를 위한 식물뿌리 기반 친환경 바이오 흡착제의 적용 – 합성수지와의 비교

Shilpa K. Bawkar,Manis K. Jha,Pankaj K. Choubey,Rukshana Parween,Rekha Panda,Pramod K. Singh,이재천 한국자원리싸이클링학회 2022 資源 리싸이클링 Vol.31 No.4

Copper is one of the non-ferrous metals used in the electrical/electronic manufacturing industries due to its superior properties particularly the high conductivity and less resistivity. The effluent generated from the surface finishing process of these industries contains higher copper content which gets discharged in to water bodies directly or indirectly. This causes severe environmental pollution and also results in loss of an important valuable metal. To overcome this issue, continuous R & D activities are going on across the globe in adsorption area with the purpose of finding an efficient, low cost and ecofriendly adsorbent. In view of the above, present investigation was made to compare the performance of a plant root (Datura root powder) as a bio-adsorbent to that of the synthetic one (Tulsion T-42) for copper adsorption from such effluent. Experiments were carried out in batch studies to optimize parameters such as adsorbent dose, contact time, pH, feed concentration, etc. Results of the batch experiments indicate that 0.2 g of Datura root powder and 0.1 g of Tulsion T-42 showed 95% copper adsorption from an initial feed/solution of 100 ppm Cu at pH 4 in contact time of 15 and 30 min, respectively. Adsorption data for both the adsorbents were fitted well to the Freundlich isotherm. Experimental results were also validated with the kinetic model, which showed that the adsorption of copper followed pseudo-second order rate expression for the both adsorbents. Overall result demonstrates that the bio-adsorbent tested has a potential applicability for metal recovery from the waste solutions/effluents of metal finishing units. In view of the requirements of commercial viability and minimal environmental damage there from, Datura root powder being an effective material for metal uptake, may prove to be a feasible adsorbent for copper recovery after the necessary scale-up studies. 구리는 우수한 특성, 특히 높은 전도성과 낮은 저항으로 인해 전기/전자 제조 산업에 널리 사용되는 비철금속 중 하나이다. 이러한 산업의 표면 처리 공정에서는 구리 함량이 높은 폐수가 발생하며, 직간접적으로 수계로 배출된다. 이는 심각한 환경 오염을 일으키고 또한귀중한 유용금속의 손실을 초래한다. 이러한 문제를 극복하기 위하여, 효율적이고 저렴하며 친환경적인 흡착제를 찾기 위한 목적으로 흡착 분야에서 전 세계적으로 지속적인 연구개발이 진행되고 있다. 이러한 점을 고려하여, 본 연구에서는 위와 같은 폐수로부터 구리 흡착을 위한 바이오 흡착제로서 식물뿌리(Datura 뿌리 분말)의 성능을 합성 흡착제(Tulsion T-42)와 비교하였다. 실험은 흡착제 투여량, 접촉시간, pH, 주입액 농도 등의 변수들을 최적화하기 위하여 회분식으로 수행되었다. 초기구리농도가 100 ppm이고 pH가 4인 주입액에서, 0.2 g Datura 뿌리 분말을 15분간 접촉하였을 때 구리 흡착율은 95%이었으며, 0.1 g Tulsion T-42은 30분간 접촉에서 95%의 흡착율을 나타내었다. 두 흡착제의 흡착 데이터는 Freundlich 등온선과 잘 일치하였으며, 유사 2차 속도식을 따르는 것을 나타내었다. 전체 결과는 본연구의 바이오 흡착제가 표면처리 공정의 폐액 또는 폐수로부터 금속 회수에 적용될 가능성을 보여주고 있다.