A refined formula for the allowable soil pressure using shear wave velocities
March 2012
Based on a variety of case histories of site investigations, including extensive bore hole data, laboratory testing and geophysical prospecting at more than 550 construction sites, an empirical formulation is proposed for the rapid determination of allowable bearing pressure of shallow foundations in soils and rocks. The proposed expression corroborates consistently with the results of the classical theory...
Forecasting the lowest cost and steel ratio of reinforced concrete simple beams using the neural network
March 2012
Given the compressive strength of concrete, yield strength of steel, span, dead and live loads, singly reinforced concrete simple beams are first optimally designed using genetic algorithms with constraints satisfying the specifications of the ACI code. The objective function is to minimize the total cost of tension steels, stirrups and concrete. A variety of beams are designed for the use of the neural...
Mechanical and hardening properties of accelerator on the cement concrete composites containing metallic reinforcements
March 2012
Research efforts in the past have been very successful in obtaining high strength concrete using various supplementary cementitious materials in concrete; however, the restriction on adding these mineral admixtures is primarily due to delayed reactivity with the hydration product of cement and the decelerated strength gain compared to plain cement concrete. Research efforts in the past have focused on the...
Simulation of the wire reverse bending test
March 2012
Steel wires are used for pre-stressing concrete structural units and for the construction of suspension bridges among other applications in civil engineering. The reverse bending and straightening of wires by rollers is employed as a routine quality check to detect laminations in wires. Experimental work on the reverse bending of wires and Finite Element (FE) simulation of bending of wires...
Pelletized fly ash lightweight aggregate concrete: A promising material
February 2012
The production of concrete requires aggregate as an inert filler to provide bulk volume as well as stiffness to concrete. Crushed aggregates are commonly used in concrete which can be depleting the natural resources and necessitates an alternative building material. This led to the widespread research on using a viable waste material as aggregates. Fly ash is one promising material which can be used as both...
The appropriate model geometrical characteristics suitable for use in an Eiffel type subsonic boundary layer wind tunnel
February 2012
The study of parameters selection of model sizing appropriate for use in an Eiffel type subsonic boundary layer wind tunnel was investigated. Using a prototype-model dimension scale of 1:300 on a 72 m, 20 storey prototype building with ratio 1:2:6; a width of 43.33, 83.33 mm breadth and 240 mm height was produced as physical model. The result of the application of methods of global modular...
A multilayer perceptron for predicting the ultimate shear strength of reinforced concrete beams
February 2012
A number of codes of practice exist that predict the maximum shear capacity of reinforced concrete beams. Since the behavior of reinforced concrete (RC) beams with non-homogeneous, non-isotropic, and nonlinear material under a combined shear and bending state of stress is very difficult to establish, these codes seem to under or over-estimate this shear capacity for many cases. This is attributed to...
Clean energies for sustainable development for built environment
January 2012
The move towards a de-carbonised world, driven partly by climate science and partly by the businessopportunities it offers, will need the promotion of environmentally friendly alternatives, if an acceptablestabilisation level of atmospheric carbon dioxide is to be achieved. This requires the harnessing and use of natural resources that produce no air pollution or greenhouse gases and provides...
Analysis by homogenisation method of structures in reinforced soil and behaviour interfaces of soil/reinforcement
January 2012
The reinforced soil is a composite material formed by the addition to a non cohesive soil of steel strip reinforcement which is able to withstand important tension forces. Through friction between the soil and the reinforcement, the ground transmits the tension forces, which develop into the mass that cannot be supported, to the steel reinforcement. The stretched reinforcements thus confer to...
An optimization solution by service science management and engineering (SSME) for using minibuses service as an alternative for private cars around Hentian Kajang in Malaysia
January 2012
There are lots of problems in Hentian Kajang: traffic congestion, unnecessary loss of fuel and global warming are only but a few of these problems. This study is an attempt to understand people's behaviour and modal choice and try to influence them, and public transport. A survey was conducted to develop the choice among private cars, minibuses and trains users, and a total of n=250 questionnaires were...
Seismic hazard and deaggregation assessment at the nuclear power plants (NPP) sites in Spain using an updated seismological database
December 2011
In this paper we present the results obtained in the seismic hazard reassessment at the sites, in the free field, of the seven Spanish nuclear power plants (NPPs), six of them are still operative till date. The computation was done using the spatially-smoothed seismicity approach, and an updated seismic catalog. In most cases, the results do not greatly differ from those previously reported. In addition, at...
Ductility demand of structures with vertical irregularities subjected to pulse-like ground motions
December 2011
The present paper addresses the seismic displacement ductility demand of structures with vertical irregularities when subjected to velocity pulse-like ground motions. Specifically, the irregularities are in strength, stiffness, and combined strength-and-stiffness in the first storey of structures. A nonlinear dynamic time history analysis was performed based on lumped mass shear-type multi-degree-of-freedom...
Manchester congestion charge scheme: A review
November 2011
Traffic is a major problem in Manchester, UK. Various methods had been considered by the local authority to cut vehicle numbers, congestion charging was widely viewed as being amongst the most effective. The widely perceived success of the London congestion pricing scheme also led Manchester to follow suit. Legislation permits British cities to introduce road pricing schemes, although they require approval of...
Risk identification techniques knowledge and application in the Brazilian construction
November 2011
The purpose of this study is to assess the use and knowledge degree of risk identification techniques in the construction industry. They are classified in residential housing construction, institutional and commercial building construction, specialized industrial construction, infrastructure and heavy construction. Therefore, we conducted a survey research by applying a questionnaire among...
Reliability studies on the Nigerian Ekki timber as bridge beam in bending under the ultimate limit state of loading
November 2011
This paper provides the results of structural reliability analysis carried out on the Nigerian Ekki timber subjected to bending forces, to ascertain its structural performance as a timber bridge beam. Samples of the Nigerian Ekki timber were collected, seasoned naturally and their structural/strength properties were determined at a moisture content of 18%, in accordance with the British Standard BS 373,...
Sustainability and value of steel recycling in Uganda
October 2011
This paper assesses the value of recycling based methods of steel manufacture in Uganda and the level at which it is likely to be successfully depended on especially if no serious iron ore exploitation is done. By analyzing the factors that underlie steel re-melting in Uganda, this study aims at highlighting the conditions that surround the reliable production of scrap based steel and the sustainability...
Characteristic studies on the mechanical properties of quarry dust addition in conventional concrete
October 2011
Currently India has taken a major initiative on developing the infrastructures such as express highways, power projects and industrial structures etc., to meet the requirements of globalization, in the construction of buildings and other structures. Concrete plays the key role and a large quantum of concrete is being utilized in every construction practices. River sand, which is one of the constituents used...
Coconut fibre: A versatile material and its applications in engineering
September 2011
This paper presents the versatility of coconut fibres and its applications in different branches of engineering, particularly in civil engineering as a construction material. Coconut fibre is one of the natural fibres abundantly available in tropical regions, and is extracted from the husk of coconut fruit.Not only the physical, chemical and mechanical properties of coconut fibres are shown; but also...
A framework of customer requirement classification and application to product configuration
September 2011
Modular structure of product family is established and the product family is decomposed into generic modules. Then, the module model denoted by attribute variable is established for each generic module. Based on the classification of customer requirement and erection of product decision tree, the description and explanation type of customer requirement can be used to restrict the sub branch of decision tree...
Effect of heavy metal and magnesium sulfate on properties of high strength cement mortar
August 2011
The effect of lead (Pb) present in mixing water on compressive strength, setting times, soundness and magnesium sulfate attack on high strength cement mortar was experimentally evaluated. Cement mortar specimens were cast using deionised water and lead (Pb) spiked deionized water for reference and the test specimens as mixing waters respectively. On comparison with reference specimens, at higher...
Reflectance spectroscopy as a tool to assess the quality of concrete in situ
August 2011
Modern high-performance concrete (HPC) is one of the most versatile, durable, and cost effective building materials known to man. Its composition has been well-characterized in 'test sample' reports from laboratory specimens and trial castings: however, its internal structure often reveals large differences from that of 'test sample concrete'. Moreover, the test procedure is considered...
Confined site construction: A qualitative investigation of critical issues affecting management of health and safety
July 2011
The construction industry is inherently risky, with a significant number of accidents and disasters occurring, particularly on confined construction sites. This research investigates and identifies the various issues affecting successful management of health and safety in confined construction sites. The rationale is that identifying the issues would assist the management of health and safety...
Influence of hybrid fibres on the post crack performance of high strength concrete: Part I experimental investigations
July 2011
This paper discusses the experimental results of tests carried out on the flexural properties of various fibre-reinforced concretes at low volume fractions of fibres upto 0.5%. The flexural properties, namely flexural strength, toughness, and ductility, were measured using four point bending tests on beam specimens. Compared to reference concrete without fibres, fibre addition was seen to enhance the pre-peak...
The effect of project types on the occurrence of rework in expanding economy
June 2011
Construction projects are complex in nature because they entail complex activities characterized with uncertainties and changes that are capable of increasing time and cost of construction projects. Rework is a waste that involves doing certain task more than once, it may not be totally eliminated but it is avoidable. It occurs as a result of so many factors ranging from omission or error in design,...
Construction planning supported in 4D interactive virtual models
June 2011
The construction of a building has been traditionally supported on the timeline schedules of the construction activities established in each case, and on technical drawings of the project. A prototype based on virtual reality (VR) technology with application to construction planning, was implemented. This interactive virtual model intends to present the project in a three-dimensional (3D) way, connected to...
Network analysis and building construction: Implications for timing and costing of activities
May 2011
The upsurge in building collapses in Nigeria recently has been a source of concern to builders, engineers, individuals and policy makers. Previous researches have observed many factors responsible for the menace, which includes; use of substandard product, poor design, and unskilled labour. None have adequately addressed the impact of timing and costing of stages in the building process as part of their key...
Design and analysis of bridge foundation with different codes
May 2011
This paper discussed the design and analysis of bridge foundation subjected to load of train with four codes, namely AASHTO code, British Standard BS Code 8004 (1986).The Chinese National Standard (CNS, 2002) and Chinese code (TB10002.5-2005). The study focused on the design and analysis of bridge’s foundation manually with the four codes and found which code is better for design and controls...
Development of profiled steel sheeting dry board roof panel system in school classroom modules
April 2011
This paper describes the latest development, application, finite element modelling and testing of a full-scale composite roof panel system which was applied as an alternative to traditional forms of roof construction. The system known as the Profiled Sheeting Steel Dry Board (PSSDB) system consists of profiled steel sheeting connected to dry board using simple mechanical connectors. Compared to traditional...
A review of design specifications of opening in the web for simply supported RC beams
April 2011
The present study reviews the design specifications of openings in the web for simply supported reinforced concrete (RC) beams and rectangular concrete beams conducted by previous researchers. A number of papers have been found to handle the reinforced concrete beams containing a series or isolated web openings. The effects of the size and location of the openings on the behavior of such beams are examined...
Seismic performance reliability analysis for reinforced concrete buildings
March 2011
Reliability analysis assessment of seismic performance for reinforced concrete buildings was investigated in this work. This was performed through the response surface methodology in order to derive explicit expression of the failure function. Two limit states defined in terms of the total building roof displacement and the maximum inter-story drift were considered. The seismic behaviour of the building was...
Artificial neural networks in calculation of telecommunication towers natural frequency
March 2011
The present paper presented the training or learning algorithms in telecommunication towers based on the artificial neural networks to calculate accurately their natural frequency in different supporting conditions. Using SAP2000 program, the real frequency is calculated and is defined as a goal function for neural network, so that all outputs of the network can be compared to this function and the error can...
A conceptual approach of the mixture proportioning technique for producing self compacting concrete
March 2011
Self Compacting Concrete (SCC) refers to a highly flowable concrete composite, designed for sufficient viscosity and cohesion to avoid segregation of aggregates. A carefree concreting practice at construction site and reduction in construction time makes SCC the most popular material among civil engineers. However, the lack of good understanding of the material properties and a reliable mixture proportioning technique...
Assessing the properties of freshly mixed concrete containing paper-mill residuals and class F fly ash
February 2011
The disposal of wastewater treatment-plant solids collected from the paper-mill has become a crucial problem as the landfill space is limited. The use of paper-mill residuals in concrete formulations was investigated as an alternative to landfill disposal. Currently, there is still lack of information on the effect of fresh properties of residual concrete. Furthermore, the effect of class F fly ash on fresh...
Flexural behaviour of cantilever concrete beams reinforced with glass fiber reinforced polymers (GFRP) bars
February 2011
The objective of the current study is to investigate and evaluate the flexural behavior of concrete cantilever beams when using locally produced GFRP bars as a longitudinal main reinforcement. The experimental program includes six concrete cantilever beams. The main parameters were the type of rebars (steel or GFRP), strength of concrete and ratios of GFRP rebars. The results of experiments were evaluated and...
A techno-economic rating system for highways using discrete multi-criteria analysis
January 2011
In developing countries, like Bangladesh, priority to upgrade a national highway is mainly based on technical aspects like daily traffic demands; whereas due consideration to economic factors is generally neglected. Based on a few parameters, if highways are rated keeping in mind some social economic attributes, significant contribution to our infrastructure-based economy could be made....
Magneto–thermo-viscoelastic material with a spherical cavity
January 2011
The present paper is concerned with a homogeneous isotropic perfect conducting viscoelastic body with a spherical cavity subjected to both ramp-type heating and external constant magnetic field. The model of the equations in the context of generalized thermoelasticity with one relaxation time is introduced. The closed form solution for distributions of displacement; temperature, strain, and stress are...
Review of the Algerian seismic design code spectrum
December 2010
The specific "seismic design spectrum" proposed by the Algerian seismic design code, namely the "normalized acceleration spectrum", seems to present an anomaly in comparison with other seismic design spectra over the world and with computed spectra, especially in the first branch of the curve, corresponding to the range of short periods, where the spectrum is a decreasing line whereas...
An experimental study on the flexural behavior of FRP RC beams and a comparison of the ultimate moment capacity with ACI
December 2010
As it is known, fiber reinforced polymer (FRP) bars are typically quite different from those of steel bars and they depend mainly on both matrix and fibers type, as well as on their volume fraction; although generally, FRP bars have lower weight, lower modulus of elasticity, but higher strength than steel. In the other hand, FRP has disadvantages, for instance: no yielding before brittle rupture and low...
Importance of spatial variability of seismic ground motion effects on long beams response
April 2010
Rigorous seismic analysis of long structures requires a complete description of the free field ground motion. At a given site, the recorded motions at distinct points are different; this may induced by loss of seismic wave’s coherency, wave passage effect, site response effect and attenuation of seismic waves. In this paper, the effects spatial variability of ground motion (SVGM) on the stochastic...
Forest roads planning and construction in Iranian forestry
April 2010
The total length of Hyrcanian forest roads in Iran at the end of year 2009 was about 10000 km. Forest roads facilitate timber harvest and attainment of other multiple use objectives requires a high capital investment. A mistake in planning a road, such as ignoring the effects of environmental and other parameters leads not only to the waste of public investment but also to adverse environmental impacts and...
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