Search results for: pull-out capacity.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1239

Search results for: pull-out capacity.

1149 Strengthening of RC Beams Containing Large Opening at Flexure with CFRP laminates

Authors: S.C. Chin, N. Shafiq, M.F. Nuruddin

Abstract:

This paper presents the study of strengthening R/C beams with large circular and square opening located at flexure zone by Carbon Fiber Reinforced Polymer (CFRP) laminates. A total of five beams were tested to failure under four point loading to investigate the structural behavior including crack patterns, failure mode, ultimate load and load deflection behaviour. Test results show that large opening at flexure reduces the beam capacity and stiffness; and increases cracking and deflection. A strengthening configuration was designed for each un-strengthened beams based on their respective crack patterns. CFRP laminates remarkably restore the beam capacity of beam with large circular opening at flexure location while 10% re-gain of beam capacity with square opening. The use of CFRP laminates with the designed strengthening configuration could significantly reduce excessive cracking and deflection and increase the ultimate capacity and stiffness of beam.

Keywords: CFRP, large opening, R/C beam, strengthening

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3781
1148 Effects of TiO2 and Nb2O5 on Hydrogen Desorption of Mg(BH4)2

Authors: Wipada Ploysuksai, Pramoch Rangsunvigit, Santi Kulprathipanja

Abstract:

In this work, effects of catalysts (TiO2, and Nb2O5) were investigated on the hydrogen desorption of Mg(BH4)2. LiBH4 and MgCl2 with 2:1 molar ratio were mixed by using ball milling to prepare Mg(BH4)2. The desorption behaviors were measured by thermo-volumetric apparatus. The hydrogen desorption capacity of the mixed sample milled for 2 h was 4.78 wt% with a 2-step released. The first step occurred at 214 °C and the second step appeared at 374 °C. The addition of 16 wt% Nb2O5 decreased the desorption temperature in the second step about 66 °C and increased the hydrogen desorption capacity to 4.86 wt% hydrogen. The addition of TiO2 also improved the desorption temperature in the second step and the hydrogen desorption capacity. It decreased the desorption temperature about 71°C and showed a high amount of hydrogen, 5.27 wt%, released from the mixed sample. The hydrogen absorption after desorption of Mg(BH4)2 was also studied under 9.5 MPa and 350 °C for 12 h.

Keywords: hydrogen storage, LiBH4, metal hydride, Mg(BH4)2

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1682
1147 Compressive Properties of a Synthetic Bone Substitute for Vertebral Cancellous Bone

Authors: H. N. Mehmanparast, J.M. Mac-Thiong., Y. Petit

Abstract:

Transpedicular screw fixation in spinal fractures, degenerative changes, or deformities is a well-established procedure. However, important rate of fixation failure due to screw bending, loosening, or pullout are still reported particularly in weak bone stock in osteoporosis. To overcome the problem, mechanism of failure has to be fully investigated in vitro. Post-mortem human subjects are less accessible and animal cadavers comprise limitations due to different geometry and mechanical properties. Therefore, the development of a synthetic model mimicking the realistic human vertebra is highly demanded. A bone surrogate, composed of Polyurethane (PU) foam analogous to cancellous bone porous structure, was tested for 3 different densities in this study. The mechanical properties were investigated under uniaxial compression test by minimizing the end artifacts on specimens. The results indicated that PU foam of 0.32 g.cm-3 density has comparable mechanical properties to human cancellous bone in terms of young-s modulus and yield strength. Therefore, the obtained information can be considered as primary step for developing a realistic cancellous bone of human vertebral body. Further evaluations are also recommended for other density groups.

Keywords: Cancellous bone, Pedicle screw, Polyurethane foam, Synthetic bone

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3058
1146 Finite Element Analysis of Thin Steel Plate Shear Walls

Authors: M. Lashgari

Abstract:

Steel plate shear walls (SPSWs) in buildings are known to be an effective means for resisting lateral forces. By using un-stiffened walls and allowing them to buckle, their energy absorption capacity will increase significantly due to the postbuckling capacity. The post-buckling tension field action of SPSWs can provide substantial strength, stiffness and ductility. This paper presents the Finite Element Analysis of low yield point (LYP) steel shear walls. In this shear wall system, the LYP steel plate is used for the steel panel and conventional structural steel is used for boundary frames. A series of nonlinear cyclic analyses were carried out to obtain the stiffness, strength, deformation capacity, and energy dissipation capacity of the LYP steel shear wall. The effect of widthto- thickness ratio of steel plate on buckling behavior, and energy dissipation capacities were studied. Good energy dissipation and deformation capacities were obtained for all models.

Keywords: low yield point steel, steel plate shear wall, thin plates, elastic buckling, inelastic buckling, post-buckling.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3198
1145 The Flexural Improvement of RC Beams Using an Inserted Plate between Concrete and FRP Bonding Surface

Authors: Woo Young Jung, Min Ho Kwon, Bu Seog Ju

Abstract:

The primary objective of this research is to improve the flexural capacity of FRP strengthened RC Beam structures with Aluminum and Titanium laminates. FRP rupture of flexural strengthened RC beams using FRP plates generally occurs at the interface between FRP plate and the beam. Therefore, in order to prevent brittle rupture and improve the ductility of the system, this research was performed by using Aluminum and Titanium materials between the two different structural systems. The research also aims to provide various strengthening/retrofitting methods for RC beam structures and to conduct a preliminary analysis of the demands on the structural systems. This was achieved by estimation using the experimental data from this research to identify a flexural capacity for the systems. Ultimately, the preliminary analysis of current study showed that the flexural capacity and system demand ductility was significantly improved by the systems inserted with Aluminum and Titanium anchor plates. Further verification of the experimental research is currently on its way to develop a new or reliable design guideline to retrofit/strengthen the concrete-FRP structural system can be evaluated.

Keywords: Reinforced Concrete, FRP Laminate, Flexural Capacity, Ductility.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2617
1144 Battery Operation Time Enhancement Based On Alternating Battery Cell Discharge

Authors: Jong-Bae Lee, Seongsoo Lee

Abstract:

This paper proposes an alternating discharge method of multiple battery cells to extend battery operation time. In the proposed method, two battery cells are periodically connected in turn to a mobile device and only one cell supply power while the other rests. Battery operation time of the connecting cell decreases due to rate-capacity effect, while that of the resting cell increases due to recovery effect. These two effects conflict each other, but recovery effect is generally larger than rate-capacity effect and battery lifetime is extended. It was found from the result that battery operation time increase about 7% by using alternating battery cell discharge.

Keywords: Battery, Recovery Effect, Rate-Capacity Effect, Low-Power, Alternating Battery Cell Discharge.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1689
1143 Integration of Hydropower and Solar Photovoltaic Generation into Distribution System: Case of South Sudan

Authors: A. Amogpai

Abstract:

Hydropower and solar photovoltaic (PV) generation are crucial in sustainability and transitioning from fossil fuel to clean energy. Integrating renewable energy sources such as hydropower and solar PV into the distributed networks contributes to achieving energy balance, pollution mitigation, and cost reduction. Frequent power outages and a lack of load reliability characterize the current South Sudan electricity distribution system. The country’s electricity demand is 300 MW; however, the installed capacity is around 212.4 MW. Insufficient funds to build new electricity facilities and expand generation are the reasons for the gap in installed capacity. The South Sudan Ministry of Energy and Dams gave a contract to an Egyptian Elsewedy Electric Company that completed the construction of a solar PV plant in 2023. The plant has a 35 MWh battery storage and 20 MW solar PV system capacity. The construction of Juba Solar PV Park started in 2022 to increase the current installed capacity in Juba City to 53 MW. The plant will begin serving 59000 residents in Juba and save 10,886.2 t of carbon dioxide (CO2) annually.

Keywords: Renewable energy, hydropower, solar energy, photovoltaic, South Sudan.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32
1142 Effect of Confinement on the Bearing Capacity and Settlement of Spread Foundations

Authors: Tahsin Toma Sabbagh, Ihsan Al-Abboodi, Ali Al-Jazaairry

Abstract:

Allowable-bearing capacity is the competency of soil to safely carries the pressure from the superstructure without experiencing a shear failure with accompanying excessive settlements. Ensuring a safe bearing pressure with respect to failure does not tolerate settlement of the foundation will be within acceptable limits. Therefore, settlement analysis should always be performed since most structures are settlement sensitive. When visualising the movement of a soil wedge in the bearing capacity criterion, both vertically and horizontally, it becomes clear that by confining the soil surrounding the foundation, both the bearing capacity and settlement values improve. In this study, two sizes of spread foundation were considered; (2×4) m and (3×5) m. These represent two real problem case studies of an existing building. The foundations were analysed in terms of dimension as well as position with respect to a confining wall (i.e., sheet piles on both sides). Assuming B is the least foundation dimension, the study comprised the analyses of three distances; (0.1 B), (0.5 B), and (0.75 B) between the sheet piles and foundations alongside three depths of confinement (0.5 B), (1 B), and (1.5 B). Nonlinear three-dimensional finite element analysis (ANSYS) was adopted to perform an analytical investigation on the behaviour of the two foundations contained by the case study. Results showed that confinement of foundations reduced the overall stresses near the foundation by 65% and reduced the vertical displacement by 90%. Moreover, the most effective distance between the confinement wall and the foundation was found to be 0.5 B.

Keywords: Bearing capacity, cohesionless soils, spread footings, soil confinement, soil modelling.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 890
1141 Numerical Modeling of Steel-Composite Hybrid Tubes Subject to Static and Dynamic Loading

Authors: Y. S. Tai, M. Y. Huang, H. T. Hu

Abstract:

The commercial finite element program LS-DYNA was employed to evaluate the response and energy absorbing capacity of cylindrical metal tubes that are externally wrapped with composite. The effects of composite wall thickness, loading conditions and fiber ply orientation were examined. The results demonstrate that a wrapped composite can be utilized effectively to enhance the crushing characteristics and energy absorbing capacity of the tubes. Increasing the thickness of the composite increases the mean force and the specific energy absorption under both static and dynamic crushing. The ply pattern affects the energy absorption capacity and the failure mode of the metal tube and the composite material property is also significant in determining energy absorption efficiency.

Keywords: fiber-reinforced metal tubes, energy absorption, axial crushing, impact loading.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2525
1140 Simulation of the Effect of Sea Water Using Ground Tank to the Flexural Capacity of GFRP Sheet Reinforced Concrete Beams

Authors: Rudy Djamaluddin, Arbain Tata, Rita Irmawaty

Abstract:

The study conducted a simulation of the effect of sea water to the bonding capacity of GFRP sheet on the concrete beams using a simulation tank. Fiber reinforced polymer (FRP) has been developed and applied in many fields civil engineering structures on the new structures and also for strengthening of the deteriorated structures. The FRP has advantages such as its corrosion resistance as well as high tensile strength to weight ratio. Compared to the other FRP materials, Glass composed FRP (GFRP) is relatively cheaper. GFRP sheet is applied externally by bonding it on the concrete surface. The studies regarding the application of GFRP sheet have been conducted such as strengthening system, bonding behavior of GFRP sheet including the application as reinforcement in new structures. For application to the structures with direct contact to sea environment, a study regarding the effect of sea water to the bonding capacity of GFRP sheet is important to be clarified. To achieve the objective of the study, a series of concrete beams strengthened with GFRP sheet on extreme tension surface were prepared. The beams then were stored on the sea water tank for six months. Results indicated the bonding capacity decreased after six month exposed to the sea water.

Keywords: GFRP sheet, sea water, concrete beams, bonding.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1868
1139 Developing Intellectual Capital to Advance Innovation and Entrepreneurial Capacity and Sustain Knowledge Economy

Authors: Hamid Alalwany, Nabeel A. Koshak, Mohammad K. Ibrahim

Abstract:

Both knowledge economy and sustainable development are considered key dimensions in the policy action lines of many developed and developing countries. In this context, universities and other higher education institutes have a vital role in developing and sustaining wellbeing communities.

In this paper, the authors’ aim is to address the links between the concepts of innovation and entrepreneurial capacity and knowledge economy, and to utilize the approach of intellectual capital development in building a sustainable knowledge economy.

The paper will contribute to two discourses:

  1. Developing a common understanding of the intersection aspects between the three concepts: Knowledge economy, Innovation and entrepreneurial system, and sustainable development.
  2. Paving the road towards developing an integrated multidimensional framework for sustainable knowledge economy.

Keywords: Innovation and Entrepreneurial Capacity, Intellectual Capital Development, Sustainable Development, Sustainable Knowledge Economy.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2269
1138 Managers’ Capacity Building for Institutional Sustainability Performance

Authors: Analiza Acuña-Villacorte

Abstract:

The Institutional Sustainability Performance (ISP) of State Universities and Colleges (SUCs) in the Philippines reveals the level of compliance and fidelity of the latter to the mandates of the state. This performance evaluation procedure aims to perpetually monitor and sustain the quality of services provided by the state institutions in the country. Importantly, the SUC level rating is one of the key indicators of the merit system adopted by the state to give incentives to government institutions. With the crucial role of the ISP and SUC level in the performance of an institution and in sustaining quality assurance, this study theorized that the top managers’ capacity to influence is the critical factor in meeting the expectations of the state. This study assessed the top managers’ capacity to influence. The hypothesis in this study proved that leadership style of top managers has significant relationship to the managers’ capacity to influence for institutional sustainability performance. Thus, the subjects of this study were restricted only to the State Universities and Colleges (SUC) that qualified in the top 20 Institutional Sustainability Performance; the digital governance performance, and the SUC leveling status nationwide. The top managers and their subordinates with doctorate of Bulacan State University and Bataan Peninsula State University whose programs have been consistently submitted to accreditation and were ranked Levels III and IV were subjected and participated to the study. This study assessed the top managers’ capacity to influence. The hypothesis in this study proved that leadership style of top managers has significant relationship to the managers’ capacity to influence for institutional sustainability performance. Thus, the subjects of this study were restricted only to the State Universities and Colleges (SUC) that qualified in the top 20 Institutional Sustainability Performance; the digital governance performance, and the SUC leveling status nationwide. The top managers and their subordinates with doctorate of Bulacan State University and Bataan Peninsula State University whose programs have been consistently submitted to accreditation and were ranked Levels III and IV were subjected and participated to the study.

Keywords: Capacity to Influence, Descriptive Design, Institutional Sustainability Performance, Management.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1903
1137 Effect of Temperature on the Water Retention Capacity of Liner Materials

Authors: Ahmed M. Al-Mahbashi, Mosleh A. Al-Shamrani, Muawia Dafalla

Abstract:

Mixtures of sand and clay are frequently used to serve for specific purposes in several engineering practices. In environmental engineering, liner layers and cover layers are common for controlling waste disposal facilities. These layers are exposed to moisture and temperature fluctuation specially when existing in unsaturated condition. The relationship between soil suction and water content for these materials is essential for understanding their unsaturated behavior and properties such as retention capacity and unsaturated follow (hydraulic conductivity). This study is aimed at investigating retention capacity for two sand-natural expansive clay mixtures (15% (C15) and 30% (C30) expansive clay) at two ambient temperatures within the range of 5 -50 °C. Soil water retention curves (SWRC) for these materials were determined at these two ambient temperatures using different salt solutions for a wide range of suction (up to 200MPa). The results indicate that retention capacity of C15 mixture underwent significant changes due to temperature variations. This effect tends to be less visible when the clay fraction is doubled (C30). In addition, the overall volume change is marginally affected by high temperature within the range considered in this study.

Keywords: Soil water retention curve, sand-expansive clay mixture, suction, temperature.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 644
1136 A Comparison between Russian and Western Approach for Deep Foundation Design

Authors: Saeed Delara, Kendra MacKay

Abstract:

Varying methodologies are considered for pile design for both Russian and Western approaches. Although both approaches rely on toe and side frictional resistances, different calculation methods are proposed to estimate pile capacity. The Western approach relies on compactness (internal friction angle) of soil for cohesionless soils and undrained shear strength for cohesive soils. The Russian approach relies on grain size for cohesionless soils and liquidity index for cohesive soils. Though most recommended methods in the Western approaches are relatively simple methods to predict pile settlement, the Russian approach provides a detailed method to estimate single pile and pile group settlement. Details to calculate pile axial capacity and settlement using the Russian and Western approaches are discussed and compared against field test results.

Keywords: Pile capacity, pile settlement, Russian approach, western approach.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 856
1135 Two Area Power Systems Economic Dispatch Problem Solving Considering Transmission Capacity Constraints

Authors: M. Zarei, A. Roozegar, R. Kazemzadeh, J.M. Kauffmann

Abstract:

This paper describes an efficient and practical method for economic dispatch problem in one and two area electrical power systems with considering the constraint of the tie transmission line capacity constraint. Direct search method (DSM) is used with some equality and inequality constraints of the production units with any kind of fuel cost function. By this method, it is possible to use several inequality constraints without having difficulty for complex cost functions or in the case of unavailability of the cost function derivative. To minimize the number of total iterations in searching, process multi-level convergence is incorporated in the DSM. Enhanced direct search method (EDSM) for two area power system will be investigated. The initial calculation step size that causes less iterations and then less calculation time is presented. Effect of the transmission tie line capacity, between areas, on economic dispatch problem and on total generation cost will be studied; line compensation and active power with reactive power dispatch are proposed to overcome the high generation costs for this multi-area system.

Keywords: Economic dispatch, Power System Operation, Direct Search Method, Transmission Capacity Constraint.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2486
1134 Reliability Based Performance Evaluation of Stone Column Improved Soft Ground

Authors: A. GuhaRay, C. V. S. P. Kiranmayi, S. Rudraraju

Abstract:

The present study considers the effect of variation of different geotechnical random variables in the design of stone column-foundation systems for assessing the bearing capacity and consolidation settlement of highly compressible soil. The soil and stone column properties, spacing, diameter and arrangement of stone columns are considered as the random variables. Probability of failure (Pf) is computed for a target degree of consolidation and a target safe load by Monte Carlo Simulation (MCS). The study shows that the variation in coefficient of radial consolidation (cr) and cohesion of soil (cs) are two most important factors influencing Pf. If the coefficient of variation (COV) of cr exceeds 20%, Pf exceeds 0.001, which is unsafe following the guidelines of US Army Corps of Engineers. The bearing capacity also exceeds its safe value for COV of cs > 30%. It is also observed that as the spacing between the stone column increases, the probability of reaching a target degree of consolidation decreases. Accordingly, design guidelines, considering both consolidation and bearing capacity of improved ground, are proposed for different spacing and diameter of stone columns and geotechnical random variables.

Keywords: Bearing capacity, consolidation, geotechnical random variables, probability of failure, stone columns.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1178
1133 Magnetic Fluid Based Squeeze Film in Rough Rotating Curved Porous Annular Plates: Deformation Effect

Authors: M. E. Shimpi, G. M. Deheri

Abstract:

This article aims to investigate the performance of a magnetic fluid based squeeze film between rotating transversely rough curved porous annular plates incorporating the effect of elastic deformation. The associated stochastically averaged Reynolds type equation is solved to obtain the pressure distribution leading to the calculation of the load carrying capacity. The results suggest that the transverse roughness of the bearing surfaces affects the performance adversely although the bearing systems register a relatively improved performance due to the magnetization. The deformation causes reduced the load carrying capacity while the curvature parameters tend to nominally increase the load carrying capacity. Besides, the adverse effect of porosity, deformation and standard deviation can be minimized to some extent by the positive effect of the magnetization and the curvature parameters in the case of negatively skewed roughness by suitably choosing the rotational inertia and the aspect ratio, which becomes significant when negative variance occurs.

Keywords: Annular plates curved rough surface, deformation, load carrying capacity, rotational inertia, magnetic fluid, squeeze film.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1826
1132 Application Research on Large Profiled Statues of Steel-Concrete Composite Shear Wall

Authors: Zhao Cai-qi, Ma Jun

Abstract:

Twin steel plates-concrete composite shear walls are composed of a pair of steel plate layers and a concrete layer sandwiched between them, which have the characteristics of both reinforced concrete shear walls and steel plate shear walls. Twin steel plates-composite shear walls contain very high ultimsate bearing capacity and ductility, which have great potential to be applied in the super high-rise buildings and special structures. In this paper, we analyzed the basic characteristics and stress mechanism of the twin steel plates-composite shear walls. Specifically, we analyzed the effects of the steel plate thickness, wall thickness and concrete strength on the bearing capacity of the twin steel plates-composite shear walls. The analysis results indicate that: (1) the initial shear stiffness and ultimate shear-carrying capacity is not significantly affected by the thickness of concrete wall but by the class of concrete, (2) both factors significantly impact the shear distribution of the shear walls in ultimate shear-carrying capacity. The technique of twin steel plates-composite shear walls has been successfully applied in the construction of an 88-meter Huge Statue of Buddha located in Hunan Province, China. The analysis results and engineering experiences showed that the twin steel plates-composite shear walls have great potential for future research and applications.

Keywords: Twin steel plates-concrete composite shear wall, huge statue of Buddha, shear capacity, initial lateral stiffness, overturning moment bearing.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2122
1131 Use of Cell Phone by Farmers and its Implication on Farmers- Production Capacity in Oyo State Nigeria

Authors: Bolarinwa, K. K., Oyeyinka, R. A.

Abstract:

Relevant agricultural information disseminator (extension agent) ratio of 1:3500 farm families which become a menace to agricultural production capacity in developing countries necessitate this study. Out of 4 zones in the state, 24 extension agents in each zone, 4 extension agents using cell phones and 120 farmers using cell phone and 120 other farmers not using cell phone were purposively selected to give 240 farmers that participated in the research. Data were collected using interview guide and analysized using frequency, percentage and t-test.. Frequency of contact with agricultural information centers revealed that cell phone user farmers had greater means score of X 41.43 contact as against the low mean X19.32 contact recorded by farmers receiving agricultural information from extension agents not using cell phone and their production was statistically significant at P < 0.05. Usage of cell phone increase extension agent contact and increase farmers- production capacity.

Keywords: Cell phone, contact, extension agents and production.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2885
1130 Evaluating the Durability and Safety of Lithium-Ion Batteries in High-Temperature Desert Climates

Authors: Kenza Maher, Yahya Zakaria, Noora S. Al-Jaidah

Abstract:

Temperature is a critical parameter for lithium-ion battery performance, life, and safety. In this study, four commercially available 18650 lithium-ion cells from four different manufacturers are subjected to accelerated cycle aging for up to 500 cycles at two different temperatures (25 °C and 45 °C). The cells are also calendar-aged at the same temperatures in both charged and discharged states for six months to investigate the effect of aging and temperature on capacity fade and state of health. The results showed that all battery cells demonstrated good cyclability and had a good state of health at both temperatures. However, the capacity loss and state of health of these cells are found to be dependent on the cell chemistry and aging conditions, including temperature. Specifically, the capacity loss is found to be higher at the higher aging temperature, indicating the significant impact of temperature on the aging of lithium-ion batteries.

Keywords: Lithium-ion battery, aging mechanisms, cycle aging, calendar aging.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 211
1129 Air Cargo Overbooking Model under Stochastic Weight and Volume Cancellation

Authors: N. Phumchusri, K. Roekdethawesab, M. Lohatepanont

Abstract:

Overbooking is an approach of selling more goods or services than available capacities because sellers anticipate that some buyers will not show-up or may cancel their bookings. At present, many airlines deploy overbooking strategy in order to deal with the uncertainty of their customers. Particularly, some airlines sell more cargo capacity than what they have available to freight forwarders with beliefs that some of them will cancel later. In this paper, we propose methods to find the optimal overbooking level of volume and weight for air cargo in order to minimize the total cost, containing cost of spoilage and cost of offloaded. Cancellations of volume and weight are jointly random variables with a known joint distribution. Heuristic approaches applying the idea of weight and volume independency is considered to find an appropriate answer to the full problem. Computational experiments are used to explore the performance of approaches presented in this paper, as compared to a naïve method under different scenarios.

Keywords: Air cargo overbooking, offloaded capacity, optimal overbooking level, revenue management, spoilage capacity.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2187
1128 Numerical Study of Modulus of Subgrade Reaction in Eccentrically Loaded Circular Footing Resting

Authors: Seyed Abolhasan Naeini, Mohammad Hossein Zade

Abstract:

This article is an attempt to present a numerically study of the behaviour of an eccentrically loaded circular footing resting on sand to determine ‎its ultimate bearing capacity. A surface circular footing of diameter 12 cm (D) was used as ‎shallow foundation. For this purpose, three dimensional models consist of foundation, and medium sandy soil was modelled by ABAQUS software. Bearing capacity of footing was evaluated and the ‎effects of the load eccentricity on bearing capacity, its settlement, and modulus of subgrade reaction were studied. Three different values of load eccentricity with equal space from inside the core on the core boundary and outside the core boundary, which were respectively e=0.75, 1.5, and 2.25 cm, were considered. The results show that by increasing the load eccentricity, the ultimate load and the ‎modulus of subgrade reaction decreased.

Keywords: Circular foundation, eccentric loading, sand, modulus of subgrade reaction.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1650
1127 Experimental Study of CO2 Absorption in Different Blend Solutions as Solvent for CO2 Capture

Authors: Rouzbeh Ramezani, Renzo Di Felice

Abstract:

Nowadays, removal of CO2 as one of the major contributors to global warming using alternative solvents with high CO2 absorption efficiency, is an important industrial operation. In this study, three amines, including 2-methylpiperazine, potassium sarcosinate and potassium lysinate as potential additives, were added to the potassium carbonate solution as a base solvent for CO2 capture. In order to study the absorption performance of CO2 in terms of loading capacity of CO2 and absorption rate, the absorption experiments in a blend of additives with potassium carbonate were carried out using the vapor-liquid equilibrium apparatus at a temperature of 313.15 K, CO2 partial pressures ranging from 0 to 50 kPa and at mole fractions 0.2, 0.3, and 0.4. Furthermore, the performance of CO2 absorption in these blend solutions was compared with pure monoethanolamine and with pure potassium carbonate. Finally, a correlation with good accuracy was developed using the nonlinear regression analysis in order to predict CO2 loading capacity.

Keywords: Absorption rate, carbon dioxide, CO2 capture, global warming, loading capacity.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1301
1126 Effect of the Truss System to the Flexural Behavior of the External Reinforced Concrete Beams

Authors: Rudy Djamaluddin, Yasser Bachtiar, Rita Irmawati, Abd. Madjid Akkas, Rusdi Usman Latief

Abstract:

The aesthetic qualities and the versatility of reinforced concrete have made it a popular choice for many architects and structural engineers. Therefore, the exploration of natural materials such as gravels and sands as well as lime-stone for cement production is increasing to produce a concrete material. The exploration must affect to the environment. Therefore, the using of the concrete materials should be as efficient as possible. According to its natural behavior of the concrete material, it is strong in compression and weak in tension. Therefore the contribution of the tensile stresses of the concrete to the flexural capacity of the beams is neglected. However, removing of concrete on tension zone affects to the decreasing of flexural capacity. Introduce the strut action of truss structures may an alternative to solve the decreasing of flexural capacity. A series of specimens were prepared to clarify the effect of the truss structures in the concrete beams without concrete on the tension zone. Results indicated that the truss system is necessary for the external reinforced concrete beams. The truss system of concrete beam without concrete on tension zone (BR) could develop almost same capacity to the normal beam (BN). It can be observed also that specimens BR has lower number of cracks than specimen BN. This may be caused by the fact that there was no bonding effect on the tensile reinforcement on specimen BR to distribute the cracks.

Keywords: External Reinforcement, Truss, Concrete Beams.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2265
1125 Limit State of Trapezoidal Metal Sheets Exposed to Concentrated Load

Authors: Kateřina Jurdová

Abstract:

In most industrial compounds are used trapezoidal metal sheets like a roof decks. These trapezoidal metal sheets are exposed by concentrated loads, usually by service loads arise from installation of air distribution, sanitary distribution, sprinkler system or wiring installation. In objects of public facilities (like shopping centre, tennis hall, etc.) they can be used for hanging advertising posters etc, too. These systems work as “building kit”. These anchoring systems are represented by clamps in shape of “V”.

This paper is occupy with recapitulation of installation systems available in trade with focus on load-bearing capacity specified by producer and on possible methods, how exactly define load bearing capacity of trapezoidal sheet loaded by concentrated load. The load bearing capacity was verified at experimental samples to determine real behavior of trapezoidal metal sheets exposed to concentrated loads.

Keywords: Clamps, concentrated load, loading test, trapezoidal metal sheet.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1717
1124 Prediction of Load Capacity of Reinforced Concrete Corbels Strengthened with CFRP Sheets

Authors: Azad A. Mohammed, Gulan B. Hassan

Abstract:

Analytical procedure was carried out in this paper to calculate the ultimate load capacity of reinforced concrete corbels strengthened or repaired externally with CFRP sheets. Strut and tie method and shear friction method proposed earlier for analyzing reinforced concrete corbels were modified to incorporate the effect of external CFRP sheets bonded to the corbel. The points of weakness of any method that lead to an inaccuracy, especially when overestimating test results were checked and discussed. Comparison of prediction with the test data indicates that the ratio of test / calculated ultimate load is 0.82 and 1.17 using strut and tie method and shear friction method, respectively. If the limits of maximum shear stress is followed, the calculated ultimate load capacity using shear friction method was found to underestimates test data considerably.

Keywords: Corbel, Strengthening, Strut and Tie Model, Shear Friction

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2754
1123 Numerical Investigation on Load Bearing Capacity of Pervious Concrete Piles as an Alternative to Granular Columns

Authors: Ashkan Shafee, Masoud Ghodrati, Ahmad Fahimifar

Abstract:

Pervious concrete combines considerable permeability with adequate strength, which makes it very beneficial in pavement construction and also in ground improvement projects. In this paper, a single pervious concrete pile subjected to vertical and lateral loading is analysed using a verified three dimensional finite element code. A parametric study was carried out in order to investigate load bearing capacity of a single unreinforced pervious concrete pile in saturated soft soil and also gain insight into the failure mechanism of this rather new soil improvement technique. The results show that concrete damaged plasticity constitutive model can perfectly simulate the highly brittle nature of the pervious concrete material and considering the computed vertical and horizontal load bearing capacities, some suggestions have been made for ground improvement projects.

Keywords: Concrete damaged plasticity, ground improvement, load bearing capacity, pervious concrete pile.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1047
1122 A Study on Improving the Flow Capacity of the Valves

Authors: A. G. Pradeep, Gorantla Giridhar Kumar, Vijay Turaga, Vinod Srinivasa

Abstract:

The major problem in the flow control valve is of lower Flow Capacity (Cv) which will reduce overall efficiency of flow circuit. Designers are continuously working to improve the Cv of the valve, but they need to validate the design ideas they have regarding the improvement of Cv. Traditional method of prototype and testing take a lot of time, that is where CFD comes into picture with very quick and accurate validation along with the visualization which is not possible with traditional testing method. We have developed a method to predict Cv value using CFD analysis by iterating on various Boundary conditions, solver settings and by carrying out grid convergence studies to establish correlation between the CFD model and Test data. The present study investigates 3 different ideas put forward by the designers for improving the flow capacity of the valves like reducing the cage thickness, changing the port position, and using the parabolic plug to guide the flow. Using CFD, we analyzed all design changes using the established methodology that we developed. We were able to evaluate the effect of these design changes on the Valve Cv. We optimized the wetted surface of the valve further by suggesting the design modification to the lower part of the valve to make the flow more streamlined. We could find that changing cage thickness and port position has little impact on the valve Cv. Combination of optimized wetted surface and introduction of parabolic plug improved the Cv of the valve significantly.

Keywords: Flow control valves, flow capacity, CFD simulations, design validation.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 441
1121 Column Size for R.C. Frames with High Drift

Authors: Sunil S. Mayengbam, S. Choudhury

Abstract:

A method to predict the column size for displacement based design of reinforced concrete frame buildings with higher target inter storey drift is reported here. The column depth derived from empirical relation as a function of given beam section, target inter-story drift, building plan features and common displacement based design parameters is used. Regarding the high drift requirement, a minimum column-beam moment capacity ratio is maintained during capacity design. The method is used in designing four, eight and twelve story frame buildings with displacement based design for three percent target inter storey drift. Non linear time history analysis of the designed buildings are performed under five artificial ground motions to show that the columns are found elastic enough to avoid column sway mechanism assuring that for the design the column size can be used with or without minor changes.

Keywords: Column size, point of contra flexure, displacement based design, capacity design.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27316
1120 The Evaluation of Load-Bearing Capacity of the Planar CHS Joint Using Finite Modeling

Authors: Anežka Jurčíková, Miroslav Rosmanit

Abstract:

The subject of this paper is to verify the behavior of the truss-type CHS joint which is beyond the scope of use of the EN 1993-1-8. This is performed by using the numerical modeling in program ANSYS and the analytical methods recommended in the CIDECT publication. The recommendations for numerical modeling of such types of joints as well as for evaluation of load-bearing capacity of the joint are given in this paper. The results from both analytical and numerical models are compared.

Keywords: ANSYS, CHS joints, FEM, Lattice structure

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1923