Abstract
Aggregates mineralogical, and petrographic properties directly affect the mechanical properties of the produced high strength. This study is focused on the effects of magmatic, sedimentary, and metamorphic aggregates on the performance of high strength concrete. In this study, the effect of the mineralogical properties of aggregates on the compressive strength and modulus of elasticity of high-strength concrete was estimated by Artifical Neural Network (ANN). To estimate the compressive strength and elasticity modules, 96 test specimens were produced. After 28 days under suitable conditions, tests were carried out to
determine the compressive strength and modulus of elasticity of the test specimens. This study also focused on the application of artificial neural networks (ANN) to predict the 28-day compressive strength and the modulus of elasticity of high-strength concrete. An ANN model is developed, trained, and tested by using the available test data obtained from the experimental studies. The ANN model is found to predict the modulus of elasticity, and 28 days compressive strength of high strength concrete well, within the ranges of the input parameters. These comparisons show that ANNs have a strong potential to predict the compressive strength and modulus of elasticity of high-strength concrete over the range of input parameters considered.
Key Words
aggregate mineralogical properties; artificial neural network; compressive strength; high strength concrete;
modulus of elasticity
Address
Mustafa Kaya, M. Aydin Kömür and Erçin Gürsel: Faculty of Engineering, Aksaray University, Aksaray, Turkey
Abstract
Although the influence of moisture content on the mechanical properties of concrete has been studied for a long time, research related to its influence on the damping and energy dissipation property of concrete structure is still very limited. In this paper, the relationship between damping property and moisture content of concrete using cyclic uniaxial compression is firstly presented, and the mechanism of the influence of moisture content on concrete damping and energy dissipation capacity is analyzed. Based on the experimental research, moisture-related damping and energy dissipation model is proposed. Results show that the dissipated energy of concrete and loss factor increase as the moisture content increasing. The energy dissipation
coefficient reflecting the influence of stress level of concrete under cyclic load, decreases first and then increases as the moisture content increasing. The mechanism of moisture-related energy dissipation behavior can be divided into the reactive force of water, the development of the internal micro cracks and the pore water pressure. Finally, the proposed moisture-related damping and energy dissipation model are verified.
Key Words
concrete; energy dissipation; experimental; material damping; moisture content
Address
Baodong Liu: School of Civil Engineering, Beijing Jiaotong University, No.3 Shangyuancun, Haidian District, Beijing, China
Pengyuan Zhang: China Construction Third Bureau Technology Innovation Development Co., Ltd., Wuhan 430000, Hubei, China
Wenjuan Lyu: Faculty of Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, 2628CN Delft, The Netherlands
Abstract
The conventional disposal methods of waste tires are harmful to the environment. Moreover, the recycling/reuse of waste tires in domestic and industrial applications is limited due to parent product's quality control and environmental concerns. Additionally, the recycling industry often prefers powdered rubber particles (<0.60 mm). However, the processing of waste tires yields both powdered and coarser (>0.60 mm) size fractions. Reprocessing of coarser rubber requires higher energy increasing the product cost. Therefore, the waste tire rubber (WTR) less favored by the recycling industry is encouraged for use in construction products as one of the environment-friendly disposal methods. In this study, WTR fiber >0.60 mm size fraction is collected from the industry and sorted into 0.60-1.18, 1.18-2.36-, and 2.36-4.75-mm sizes. The effects of different fiber size fractions are studied by incorporating it as fine aggregates at 10%, 20%, and 30% in the self-compacting rubberized concrete (SCRC). The experimental investigations are carried out by performing fresh and hardened state tests. As the fresh state tests, the slump-flow, T500, V-funnel, and L-box are performed. As the hardened state tests, the scanning electron microscope, compressive strength, flexural strength and split tensile strength tests are conducted. Also, the water absorption, porosity, and ultrasonic pulse velocity tests are performed to measure durability. Furthermore, SCRC's energy absorption capacity is evaluated using the falling weight impact test. The statistical significance of content and size fraction of WTR fiber on SCRC is evaluated using the analysis of variance (ANOVA). As the general conclusion, implementation of various size fraction WTR fiber as fine aggregate showed potential for producing concrete for construction applications. Thus, use of WTR fiber in concrete is suggested for safe, and feasible waste tire disposal.
Key Words
ANOVA; impact energy; microstructure; self-compacting concrete; waste rubber; water permeability
Address
Akshay A. Thakare: Department of Civil Engineering, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
Salman Siddique: Department of Civil Engineering, Center for Advanced Construction Materials, University of Texas at Arlington, Nedderman Hall, Arlington, TX 76010, USA
Amardeep Singh: Department of Civil and Architectural Engineering, Changzhou Institute of Technology, Jiangsu, 213032 China
Trilok Gupta: Department of Civil Engineering, College of Technology and Engineering, Maharana Pratap University of Agriculture & Technology, Udaipur, 313001, India
Sandeep Chaudhary: Department of Civil Engineering, Indian Institute of Technology Indore, Simrol, Indore, 453552, India; Center for Rural Development and Technology, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
Abstract
In present study, the nonlocal Flügge shell model based is utilized to investigate the vibration characteristics of
armchair and chiral single-walled carbon nanotubes with impact of small-scale effect subjected to two boundary supports. The wave propagation approach is employed to determine eigen frequencies for armchair and chiral tubes. The fundamental frequencies scrutinized with assorted aspect ratios by varying the bending rigidity. The raised in value of nonlocal parameter reduces the corresponding fundamental frequency. It is investigated with higher aspect ratio, the boundary conditions have a momentous influence on vibration of CNT. It is concluded that frequencies would increase by increasing of the bending rigidity. Solutions of the frequency equation have determined by writing in MATLAB coding.
Abstract
Solid waste management is of great concern in today's world. An enormous amount of waste is generated from various industrial activities. Concrete production utilizing some of the potential waste materials will add to the benefit of society. These benefits will include reduction of landfill burden, improved air quality, riverbed protection due to excessive sand excavation, economical concrete production and much more. This study aims to utilize waste granite powder (GP) originating from granite industries as a sand replacement in concrete. Fine GP was collected in the form of slurry from different granite cutting industries. In this study, GP was added in an interval of ten percent as 10%, 20%, 30%, 40% and 50% by weight of sand in concrete. Mechanical assets; compressive strength, flexural strength and splitting tensile strength were prominent for control
and blended mixes. Modulus of elasticity (MoE) and abrasion tests were also performed on control and blended specimens of concrete. To provide a comprehensive clarification for enhanced performance of GP prepared concrete samples, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed. Results indicate that 30% replacement of sand by weight with GP enhances the mechanical assets of concrete and even the results obtained for 50% replacement are also acceptable. Comprehensive analysis through SEM and XRD for 30% replacement was better than control one. The performance of GP added to concrete in terms of abrasion and modulus of elasticity was far better than the control mix. A significant outcome shows the appropriateness of granite fines to produce sustainable and environmentally friendly concrete.
Key Words
abrasion; concrete; granite powder; mechanical properties; modulus of elasticity
Address
Kishan Lal Jain: Department of Civil Engineering, Swami Keshvanand Institute of Technology, Management and Gramothan, Ram Nagariya Road, Jagatpura, Jaipur, Rajasthan, 302017, India
Gaurav Sancheti: Department of Civil Engineering, Manipal University Jaipur, Dehmi Kalan, Jaipur, Rajasthan, 303007, India
Abstract
In this paper, vibrational attributes of double-walled carbon nanotubes (CNTs) has been studied based upon nonlocal
elastic shell theory. The implication of small scale is being perceived by establishing nonlocal Love shell model. The wave propagation approach has been operated to frame the governing equations as eigen value system. The comparison of local and nonlocal model has been overtly explored by means of scaling parameter. An appropriate selection of material properties and nonlocal parameter has been considered. The influence of changing mechanical parameter Young's modulus has been studied in detail. The dominance of end condition via nonlocal parameter is explained graphically. The results generated furnish the evidence regarding applicability of nonlocal shell model and also verified by earlier published literature.
Key Words
double-walled CNTs; Love shell theory; nonlocal parameter; Poisson
Address
Muzamal Hussain, Sehar Asghar: Department of Mathematics, Govt. College University Faisalabad, 38040, Faisalabad, Pakistan
Mohamed Amine Khadimallah: Prince Sattam Bin Abdulaziz University, College of Engineering, Civil Engineering Department, Al-Kharj, 16273, Saudi Arabia
Hamdi Ayed: Department of Civil Engineering, College of Engineering, King Khalid University, Abha, Kingdom of Saudi Arabia; Higher Institute of Transport and Logistics of Sousse, University Sousse, Tunisia
Essam Mohammed Banoqitah: Nuclear Engineering Department, Faculty of Engineering, King Abdulaziz University, Jeddah P.O. Box 80204, Jeddah 21589, Saudi Arabia
Hassen Loukil: Department of Electrical Engineering, College of Engineering, King Khalid University, Abha, 61421, Saudi Arabia
Imam Ali: Prince Sattam Bin Abdulaziz University, College of Engineering, Civil Engineering Department, Al-Kharj, 16273, Saudi Arabia
S.R. Mahmoud: GRC Department, Faculty of Applied studies, King Abdulaziz University, Jeddah, Saudi Arabia
Abdelouahed Tounsi: YFL (Yonsei Frontier Lab), Yonsei University, Seoul, Korea; Department of Civil and Environmental Engineering, King Fahd University of Petroleum and Minerals, 31261 Dhahran, Eastern Province, Saudi Arabia
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