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Full-Text Articles in Engineering

Changes In Heavy Rainstorm Characteristics With Time And Temperature, Barry A. Palynchuk Phd, Yiping Guo Phd Apr 2015

Changes In Heavy Rainstorm Characteristics With Time And Temperature, Barry A. Palynchuk Phd, Yiping Guo Phd

Barry A. Palynchuk PhD

The effects of climate change upon extreme rainfall is evaluated, based upon the identification of individual storms, and the changes in their statistical parameters and distributions. Those changes will be measured based upon historical time spans, and climatic temperature associated with the events. A brief review and comparison with other research is provided.


Changes In Heavy Rainstorm Characteristics With Time And Temperature - Presentation, Barry A. Palynchuk Phd Apr 2015

Changes In Heavy Rainstorm Characteristics With Time And Temperature - Presentation, Barry A. Palynchuk Phd

Barry A. Palynchuk PhD

The effects of climate change upon extreme rainfall is evaluated, based upon the identification of individual storms, and the changes in their statistical parameters and distributions. Those changes will be measured based upon historical time spans, and climatic temperature associated with the events. A brief review and comparison with other research provided.


Strengthening And Evaluation Of Reinforced Concrete Beams For Flexure By Using External Steel Reinforcements, Innovative Research Publications Irp India, Akhtar Gul, Bashir Alam, Fayaz A Khan, Yasir Irfan Badrashi, Khan Shahzada Apr 2015

Strengthening And Evaluation Of Reinforced Concrete Beams For Flexure By Using External Steel Reinforcements, Innovative Research Publications Irp India, Akhtar Gul, Bashir Alam, Fayaz A Khan, Yasir Irfan Badrashi, Khan Shahzada

Innovative Research Publications IRP India

The most implementable and favorable technique, used for the flexural strengthening of reinforced concrete (RC) beams is the attachment of external steel members. Attachment of external steel sections or fiber reinforced polymers is considered as a common technique used for the enhancement of flexural capacity of the existing structural elements. To investigate and evaluate the flexural capacity of reinforced concrete beams, strengthened with external steel bars, a research study was carried out and is presented in this paper. Three reinforced concrete beams reinforced with minimum reinforcement ratio were constructed and tested. Two beams were strengthened by attaching external steel bars …


Finite Element Modelling Of Modular Precast Composites For Railway Track Support Structure – A Battle To Save Sydney Harbour Bridge, Dane Griffin, Olivia Mirza, Kenny Kwok, Sakdirat Kaewunruen Apr 2015

Finite Element Modelling Of Modular Precast Composites For Railway Track Support Structure – A Battle To Save Sydney Harbour Bridge, Dane Griffin, Olivia Mirza, Kenny Kwok, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Railway networks in Australian alone require replacing a large amount of aging timber components in excess of 280,000 m3 per year. The replacement of timber track components is responsible for producing greenhouse gas emissions 6 times greater than equivalent reinforced concrete counterparts. Sydney Harbour Bridge presently experiences similar problem. A feasibility study to develop an innovative solution for the replacement of aging timber transoms installed on the Sydney Harbour Bridge was conducted to evaluate environmental, safety and financial benefits. The development of alternative composite structure to replace the timber components overcomes some potential compatibility issues with track stiffness as well …


Prediction Of Unconfined Compressive Strength Of Pulverized Fuel Ash-Cement-Sand Mixture Apr 2015

Prediction Of Unconfined Compressive Strength Of Pulverized Fuel Ash-Cement-Sand Mixture

Faculty of Engineering University of Malaya

Recently, ground improvement has become much more feasible. Chemical stabilization is a quick and affordable approach to enhancing soil characteristics. An important avenue of research is discovering alternative materials for use in soil enhancement. Pulverized fuel ash (PFA), which is a waste byproduct of coal power plants, has been shown to reduce the environmental risks and costs involved in construction. In this study, a series of unconfined compressive tests were performed for various mixtures of cement, PFA, and sand; the tests considered both the curing period and the optimum moisture content (OMC). In addition, multiple variable linear regression was used …


Eggshells: A Novel Bio-Filler For Intumescent Flame-Retardant Coatings Apr 2015

Eggshells: A Novel Bio-Filler For Intumescent Flame-Retardant Coatings

Faculty of Engineering University of Malaya

The aim of this study was to develop intumescent flame-retardant coatings that incorporate chicken eggshell (CES) waste as a novel eco-friendly bio-filler. Three flame-retardant additives, namely, ammonium polyphosphate phase II, pentaerythritol and melamine were mixed with flame-retardant fillers and acrylic binder to synthesize the intumescent coatings. The fire performance of the coatings was evaluated in accordance with 'BS 476: Part 6-Fire Propagation' and 'BS 476: Part 7-Surface Spread of Flame' test standards. It was found that 4 out of 5 of the coated specimens (B, C, D and E) neither showed surface spread of flame nor any afterglow combustion upon …


Zastosowanie Systemu Modeli Calmet/Calpuff O Wysokiej Rozdzielczości Do Oceny Wpływu Na Jakość Powietrza Spalarni Odpadów Komunalnych W Krakowie, Mateusz Rzeszutek, Robert Oleniacz Mar 2015

Zastosowanie Systemu Modeli Calmet/Calpuff O Wysokiej Rozdzielczości Do Oceny Wpływu Na Jakość Powietrza Spalarni Odpadów Komunalnych W Krakowie, Mateusz Rzeszutek, Robert Oleniacz

Robert Oleniacz

In this paper there was presented a comprehensive assessment of the impact on air for the Municipal Solid Waste Incineration (MSWI) plant in Krakow with the planned start of operation by the end of 2015. Construction of the plant started in autumn 2013 in the district of Nowa Huta in Krakow. Modeling of the spread of pollutants in ambient air was conducted using an advanced multi-layer cloud CALPUFF Gaussian model, whose algorithms include, among other things, diversity of terrain. Spatial data of land area in the admitted computational domain are obtained from digital terrain model Shuttle Radar Topography Mission (SRTM3) …


Flexural Behaviour Of Rc Beams Strengthened With Wire Mesh-Epoxy Composite Mar 2015

Flexural Behaviour Of Rc Beams Strengthened With Wire Mesh-Epoxy Composite

Faculty of Engineering University of Malaya

In this research work, the flexural behaviour of reinforced concrete (RC) beams strengthened with a new type of strengthening material, namely wire mesh-epoxy composite, was investigated. The flexural behaviour of RC beams strengthened using this new material was compared with RC beams strengthened with carbon fibre reinforced polymer (CFRP) sheet. In addition, the structural performance of a beam strengthened using a hybrid of wire mesh-epoxy and CFRP sheet was investigated. The results showed that the use of wire mesh-epoxy composite provides considerable enhancement in the performance of strengthened beams. Compared to CFRP, the wire mesh-epoxy strengthened beams showed more improvement …


Innovative Hybrid Bonding Method For Strengthening Reinforced Concrete Beam In Flexure Mar 2015

Innovative Hybrid Bonding Method For Strengthening Reinforced Concrete Beam In Flexure

Faculty of Engineering University of Malaya

This paper presents the test results of the experimental behavior of reinforced concrete (RC) beams strengthened with the newly proposed hybrid bonding technique, which is the wise combination of plate bonding and near surface mounting (NSM) technique. Many studies have focused on the experimental behavior of RC beams strengthened with externally bonded steel plates. However, the presence of high interfacial shear stresses at the end of the plate may reduce the resistance to failure of the strengthened structure. Recently, to a certain extent, the development of the near surface mounted strengthening technique can reduce the problem of this premature end …


Stiffness Modulus Of Polyethylene Terephthalate Modified Asphalt Mixture: A Statistical Analysis Of The Laboratory Testing Results Mar 2015

Stiffness Modulus Of Polyethylene Terephthalate Modified Asphalt Mixture: A Statistical Analysis Of The Laboratory Testing Results

Faculty of Engineering University of Malaya

Stiffness of asphalt mixture is a fundamental design parameter of flexible pavement. According to literature, stiffness value is very susceptible to environmental and loading conditions. In this paper, effects of applied stress and temperature on the stiffness modulus of unmodified and Polyethylene Terephthalate (PET) modified asphalt mixtures were evaluated using Response Surface Methodology (RSM). A quadratic model was successfully fitted to the experimental data. Based on the results achieved in this study, the temperature variation had the highest impact on the mixture's stiffness. Besides, PET content and amount of stress showed to have almost the same effect on the stiffness …


Manganese Removal By Low Cost Adsorbent From Synthetic Wastewater-A Review, Innovative Research Publications Irp India, Vinod Pahade, A. K. Sharma Mar 2015

Manganese Removal By Low Cost Adsorbent From Synthetic Wastewater-A Review, Innovative Research Publications Irp India, Vinod Pahade, A. K. Sharma

Innovative Research Publications IRP India

Manganese (Mn) is one of the most abundant metals in Earth’s crust. Manganese is present in ground water as a divalent ion (Mn2+) and is considered a pollutant mainly because of its organoleptic properties. It is an essential metal for the human system and many enzymes are activated by manganese. Therefore, manganese has to be removed from some waters and wastewaters for various reasons. Conventional chemical and physical treatments for Mn(II) removal from contaminated effluent consist of precipitation, depth filtration, ion exchange, adsorption and oxidation. The adsorption technique has been found to be one of the most effective for the …


Modelling The Effect Of Income And Car Ownership On Recreational Trip In Akure ,Nigeria, Innovative Research Publications Irp India, Busari Ayobami Adebola, Owolabi Adebayo, Modupe Abayomi Emmanuel Mar 2015

Modelling The Effect Of Income And Car Ownership On Recreational Trip In Akure ,Nigeria, Innovative Research Publications Irp India, Busari Ayobami Adebola, Owolabi Adebayo, Modupe Abayomi Emmanuel

Innovative Research Publications IRP India

The effect of income and car ownership on recreational trip pattern in the study area was analysed, focusing on the frequency of trips, modal choice and the land use pattern. It is an attempts to extend research on travel characteristics and behaviour to cities of the developing world with focus on Akure metropolis.


A Review Of Survivability And Remedial Actions Of Tidal Current Turbines Mar 2015

A Review Of Survivability And Remedial Actions Of Tidal Current Turbines

Faculty of Engineering University of Malaya

Tidal current energy is one of the most predictable ocean renewable energies. Survivability of the device used to harness tidal power and its remedial actions are critical to ensure a successful power generation. Marine environment is harsh with the continuous attacks of waves, current saline water and microorganism. Support structures are discussed including gravity base, monopile, tripod/piled jacket and floating structure. Extreme weather increases the wave height and current speed to produce high loading at the turbine. Support structure is designed to sustain the loadings from the extreme weather. Protective seabed unit should be included to prevent the seabed scouring. …


Using Local Stiffness Indicator To Examine The Effect Of Honeycombs On The Flexural Stiffness Of Reinforced Concrete Beams Mar 2015

Using Local Stiffness Indicator To Examine The Effect Of Honeycombs On The Flexural Stiffness Of Reinforced Concrete Beams

Faculty of Engineering University of Malaya

Experimental modal analysis was performed on RC beams with honeycombs. The mode shapes were extracted, and the eigenvectors were used in determining the mode shape equations using nonlinear regression. The equation used in the regression was the generalized solution of transverse vibration of a Bernoulli-Euler prismatic beam. By utilizing the regressed phase variable, the global flexural stiffness was evaluated. It was observed that the global stiffness dropped with increasing volumes of the honeycombs in the beam. The results were compared with values computed using the secant modulus from the load-deflection plot obtained upon loading at each load stage and the …


Optimal Crop Water Allocation Based On Constraint-State Method And Nonnormal Stochastic Variable Mar 2015

Optimal Crop Water Allocation Based On Constraint-State Method And Nonnormal Stochastic Variable

Faculty of Engineering University of Malaya

Integrated and holistic approach of water resources management is important for sustainability. Since the optimum use of water resources needs taking into account different environmental issues. Accordingly, the use of supportive models in decision making as an effective tool is significantly important. To addressing uncertainty in crop water allocation, several methodologies have been proposed. The most of these models consider rainfall as a stochastic variable affecting soil moisture. Applying a new methodology/model while considering the stochastic variable in nonnormal state and uncertainties for both irrigation depth and soil moisture looks more realistic. In this research, a mathematical model was developed …


Application Of A Novel Catalyst In The Esterification Of Mixed Industrial Palm Oil For Biodiesel Production Mar 2015

Application Of A Novel Catalyst In The Esterification Of Mixed Industrial Palm Oil For Biodiesel Production

Faculty of Engineering University of Malaya

Mixed industrial palm oil (MIPO) is proposed in this study as a renewable and agro-industrial raw material to produce biodiesel fuel. MIPO was obtained by mixing of acidic crude palm oil with sludge palm oil. Due to the high level of free fatty acid (FFA) in MIPO (8.5 %), esterification is needed to remove the acidity to the minimum level before biodiesel production. This is the first time 1-propanesulphonic acid (1-PSA) has been introduced as a catalyst for the pretreatment of MIPO. Using optimum conditions, the FFA content was successfully reduced from 8.5 % to less than 1 %. The …


Feasibility Study Of High Volume Slag As Cement Replacement For Sustainable Structural Lightweight Oil Palm Shell Concrete Mar 2015

Feasibility Study Of High Volume Slag As Cement Replacement For Sustainable Structural Lightweight Oil Palm Shell Concrete

Faculty of Engineering University of Malaya

This paper presents a study on the use of high volume slag as a cement replacement material, and waste oil palm shell (OPS) as a lightweight aggregate to produce a sustainable lightweight concrete (LWC). In order to establish the feasibility of such concrete for structural purposes, the first part of the paper deals with the investigation of the mechanical and bond properties of OPS concrete (OPSC) with varying slag content. The results showed that even though an increase in the slag content led to the reduction in the strength, the OPSC with slag as a 60% cement replacement material exhibited …


Feasibility Study Of High Volume Slag As Cement Replacement For Sustainable Structural Lightweight Oil Palm Shell Concrete Mar 2015

Feasibility Study Of High Volume Slag As Cement Replacement For Sustainable Structural Lightweight Oil Palm Shell Concrete

Faculty of Engineering University of Malaya

This paper presents a study on the use of high volume slag as a cement replacement material, and waste oil palm shell (OPS) as a lightweight aggregate to produce a sustainable lightweight concrete (LWC). In order to establish the feasibility of such concrete for structural purposes, the first part of the paper deals with the investigation of the mechanical and bond properties of OPS concrete (OPSC) with varying slag content. The results showed that even though an increase in the slag content led to the reduction in the strength, the OPSC with slag as a 60% cement replacement material exhibited …


The Impacts Of Climate Change Policies On The Transportation Sector Mar 2015

The Impacts Of Climate Change Policies On The Transportation Sector

Faculty of Engineering University of Malaya

This study examines the impact of carbon tax and its alternative, energy tax, on both the Malaysian economy and the transport sector, using a CGE (Computable General Equilibrium) framework. In order to achieve government revenue neutrality, two schemes for revenue recycling, namely lump-sum transfer and labour tax recycling, are employed. The simulation's results show that the carbon tax policy is more effective than the energy tax policy in reducing carbon emissions; because it is less expensive. The negative impact of the carbon tax, on real GDP (Gross Domestic Product) and investment, is less than the energy tax in both recycling …


Kinetics Of Superoxide Ion In Dimethyl Sulfoxide Containing Ionic Liquids Mar 2015

Kinetics Of Superoxide Ion In Dimethyl Sulfoxide Containing Ionic Liquids

Faculty of Engineering University of Malaya

The chemical generation of superoxide ion (O-2 (aEuro cent a')) by dissolving potassium superoxide was investigated. The chemically generated O-2 (aEuro cent a') was then used to study the long-term stability of O-2 (aEuro cent a') in dimethyl sulfoxide (DMSO) containing ionic liquids (ILs) and determine the rate constants based on pseudo 1st- and 2nd-order reactions between the IL and O-2 (aEuro cent a') generated in DMSO. O-2 (aEuro cent a') was unstable in DMSO containing [S-222][TFSI], [DMIm][MS], [BDMIm][TfO], [EMIm][TFSI], [EMIm][MS], [P-14,P-666][TPTP], [P-14,P-666][TFSI], and all pyridinium-based ILs. In contrast, O-2 (aEuro cent a') was very stable in DMSO containing [MOPMPip][TFSI], …


Soft Computing Methodologies For Estimation Of Bridge Girder Forces With Perforations Under Tsunami Wave Loading Mar 2015

Soft Computing Methodologies For Estimation Of Bridge Girder Forces With Perforations Under Tsunami Wave Loading

Faculty of Engineering University of Malaya

Tsunamis pose a great threat to coastal infrastructures. Bridges without adequate provisions for earthquake and tsunami loading generally are vulnerable when a tsunami occurs. During the last two disastrous tsunami events (i.e., the tsunami in the Indian Ocean and the tsunami that struck Japan), many bridges were damaged by the waves created by the tsunamis. In this paper, in order to address this crucial problem, we used soft computing techniques to design and develop a process that simulates the effects of perforations in the girders of bridges on reducing the forces applied on the bridge when a tsunami occurs. Soft …


Engineering And Sustainability Performance Of Self-Compacting Palm Oil Mill Incinerated Waste Concrete Feb 2015

Engineering And Sustainability Performance Of Self-Compacting Palm Oil Mill Incinerated Waste Concrete

Faculty of Engineering University of Malaya

The different stages in the processing of palm oil generate various types of waste by-products, which have to be disposed of appropriately for a cleaner environment and to reduce pollution. In this study, palm oil clinker (POC), one of the by-products of the palm oil mill, was utilized in the production of self-compacting concrete (SCC). SCC has diverse types of structural application due to its own enhanced self-consolidating behaviour. The proportioning of the mixes was based on particle packing, which integrates both aggregate packing and void volume for a mix of aggregates. Combinations of POC and natural aggregate were studied …


Geometric Design Steps Of The Upper Toggle-Brace-Damper System, Innovative Research Publications Irp India, Zhefei Zhao, Ricky W.K. Chan Feb 2015

Geometric Design Steps Of The Upper Toggle-Brace-Damper System, Innovative Research Publications Irp India, Zhefei Zhao, Ricky W.K. Chan

Innovative Research Publications IRP India

The design procuress for toggle-brace-damper system is to complex. Particularly for those engineers who not have any much experiences in this area. In this paper, a comprehensive economic geometric design steps of the novel toggle-brace-damper system to enhance in new or retrofit existing structure is presented. Nonlinear time history analyses are carried out in Opensees.


Assessment Of Ghg Emission Reduction Potential From Source-Separated Organic Waste (Sow) Management: Case Study In A Higher Educational Institution In Malaysia Feb 2015

Assessment Of Ghg Emission Reduction Potential From Source-Separated Organic Waste (Sow) Management: Case Study In A Higher Educational Institution In Malaysia

Faculty of Engineering University of Malaya

In Malaysia, the greenhouse gases (GHGs) emissions reduction via composting of source-separated organic waste (SOW) in municipal solid waste (MSW) has not been assessed. Assessment of GHG emissions reduction via composting of SOW is important as environmental impacts from waste management are waste-specific and local-specific. The study presents the case study for potential carbon reduction via composting of SOW in University of Malaya (UM). In this study, a series of calculations were used to evaluate the GHG emission of different SOW management scenarios. The calculations based on IPCC calculation methods (AM0025) include GHGs emissions from landfilling, fuel consumption in transportation …


Lead Sorption By Carbon Nanofibers Grown On Powdered Activated Carbon - Kinetics And Equilibrium Feb 2015

Lead Sorption By Carbon Nanofibers Grown On Powdered Activated Carbon - Kinetics And Equilibrium

Faculty of Engineering University of Malaya

Carbon nanofibers (CNFs) were synthesized by using a safe and less hazardous method, compared to using floating catalysts in chemical vapor deposition (CVD) process. This process used C2H2 as carbon source and oil palm kernel shell-based powdered activated carbon (PAC) as cheap solid substrate. Use of nickel (Ni2+) impregnated PAC as fixed substrate for the synthesis of CNF is one of the novelties of the research work accomplished by the authors. The PAC CNFs porous nanocomposite product was used for the sorption of lead ions (Pb2+) from synthetic aqueous solution. Kinetics of Pb2+ adsorption and isotherms were investigated by varying …


Flexural Behavior Of Engineered Cementitious Composite (Ecc) Slabs With Polyvinyl Alcohol Fibers Jan 2015

Flexural Behavior Of Engineered Cementitious Composite (Ecc) Slabs With Polyvinyl Alcohol Fibers

Faculty of Engineering University of Malaya

This paper investigates the effects of polyvinyl alcohol (PVA) fibers on the toughness, compressive and flexural strength of engineered cementitious composite (ECC) cubes and slabs. The key parameter discussed in this study is the reinforcing index. To evaluate the strain-hardening behavior of ECC with different PVA fiber contents, tests were conducted in direct tension. Flexural toughness was also evaluated following ASTM C 1018 procedure and post-cracking strength technique (PCSm). Results showed that the compressive strength decreases as the reinforcing index increases in a nonlinear trend. By increasing the reinforcing index, the first crack load decreases and ultimate strength slightly increases. …


Supplementary Cementitious Materials Origin From Agricultural Wastes - A Review Jan 2015

Supplementary Cementitious Materials Origin From Agricultural Wastes - A Review

Faculty of Engineering University of Malaya

Concrete is heavily used as a construction material in modern society. With the growth in urbanization and industrialization, the demand for concrete is increasing day by-days. Therefore, raw materials and natural resources are required in large quantities for concrete production worldwide. At the same time, a considerable quantity of agricultural waste and other types of solid material disposal are posing serious environmental issues. To minimize and reduce the negative impact of the concrete industry through the explosive usage of raw materials, the use of agricultural wastes as supplementary cementitious materials, the source of which are both reliable and suitable for …


Long-Term Response Prediction Of Skewed Integral Bridges Under Creep Effects, Innovative Research Publications Irp India, Akilu Muhammad, Redzuan Abdullah, Ibrahim Ogiri Hassan Jan 2015

Long-Term Response Prediction Of Skewed Integral Bridges Under Creep Effects, Innovative Research Publications Irp India, Akilu Muhammad, Redzuan Abdullah, Ibrahim Ogiri Hassan

Innovative Research Publications IRP India

A research was carried out to assess the effect of concrete creep on long-term performance of skewed Integral Abutment Bridge. Time-history transient analysis was conducted using Finite Element method for 75-year period. Parametric study was conducted in LUSAS to assess the effect of bridge total length (60m,90m,150m), skew angles (00 ,100 ,200 ,300 ,400 ), backfill soil stiffness (dense sand, loose sand) on the behaviour of the bridge measured by girder and abutment displacement, moment and shears. Three dimensional nonlinear thick beam element with CEP-FIP 1990 creep material properties was used to model bridge girders. Other structural members were modelled …


Chemical Modification Of Byrsonima Crassifolia With Citric Acid For The Competitive Sorption Of Heavy Metals From Water, Jacqueline Monroy-Figueroa, Didilia I. Mendoza-Castillo, Adrian Bonilla-Petriciolet, María Ana Pérez-Cruz Jan 2015

Chemical Modification Of Byrsonima Crassifolia With Citric Acid For The Competitive Sorption Of Heavy Metals From Water, Jacqueline Monroy-Figueroa, Didilia I. Mendoza-Castillo, Adrian Bonilla-Petriciolet, María Ana Pérez-Cruz

Adrian Bonilla-Petriciolet

This study reports the chemical modification of the Byrsonima Crassifolia biomass with citric acid to improve its sorption properties for the removal of cadmium and nickel ions from aqueous solutions under competitive sorption conditions (i.e., multicomponent solutions). The best operating conditions of the chemical modification process were identified using the signal-to-noise ratio to enhance the metal uptakes and to reduce the competitive sorption effects during the simultaneous removal of these metals using the modified biomass. Results indicated that both the sorption capacity and selectivity for heavy metal removal can be improved in multicomponent metal solutions. This improvement in sorption properties …


Strengthening The Rail Mode Of Transport By Condition Based Preventive Maintenance, René Schenkendorf, Jörn Groos, Lars Johannes Jan 2015

Strengthening The Rail Mode Of Transport By Condition Based Preventive Maintenance, René Schenkendorf, Jörn Groos, Lars Johannes

René Schenkendorf

No abstract provided.