Abstract: Malaysia is rich with historic buildings, particularly in
Penang and Malacca states. Restoration activities are increasingly
important as these states are recognized under UNESCO World
Heritage Sites. Restoration activities help to maintain the uniqueness
and value of a heritage building. However, increasing in restoration
activities has resulted in large quantities of waste. To cope with this
problem, the 3R concept (reduce, reuse and recycle) is introduced.
The 3R concept is one of the waste management hierarchies. This
concept is still yet to apply in the building restoration industry
compared to the construction industry. Therefore, this study aims to
promote the 3R concept in the heritage building restoration industry.
This study aims to examine the importance of 3R concept and to
identify challenges in applying the 3R concept in the heritage
building restoration industry. This study focused on contractors and
consultants who are involved in heritage restoration projects in
Penang. Literature review and interviews helps to reach the research
objective. Data that obtained is analyzed by using content analysis.
For the research, application of 3R concept is important to conserve
natural resources and reduce pollution problems. However, limited
space to organise waste is the obstruction during the implementation
of this concept. In conclusion, the 3R concept plays an important role
in promoting environmental conservation and helping in reducing the
construction waste.
Abstract: Factors affecting construction unit cost vary
depending on a country’s political, economic, social and
technological inclinations. Factors affecting construction costs have
been studied from various perspectives. Analysis of cost factors
requires an appreciation of a country’s practices. Identified cost
factors provide an indication of a country’s construction economic
strata. The purpose of this paper is to identify the essential factors
that affect unit cost estimation and their breakdown using artificial
neural networks. Twenty five (25) identified cost factors in road
construction were subjected to a questionnaire survey and employing
SPSS factor analysis the factors were reduced to eight. The 8 factors
were analysed using neural network (NN) to determine the
proportionate breakdown of the cost factors in a given construction
unit rate. NN predicted that political environment accounted 44% of
the unit rate followed by contractor capacity at 22% and financial
delays, project feasibility and overhead & profit each at 11%. Project
location, material availability and corruption perception index had
minimal impact on the unit cost from the training data provided.
Quantified cost factors can be incorporated in unit cost estimation
models (UCEM) to produce more accurate estimates. This can create
improvements in the cost estimation of infrastructure projects and
establish a benchmark standard to assist the process of alignment of
work practises and training of new staff, permitting the on-going
development of best practises in cost estimation to become more
effective.
Abstract: Self-compacting concrete (SCC) developed in Japan
in the late 80s has enabled the construction industry to reduce
demand on the resources, improve the work condition and also
reduce the impact of environment by elimination of the need for
compaction. Fuzzy logic (FL) approaches has recently been used to
model some of the human activities in many areas of civil
engineering applications. Especially from these systems in the model
experimental studies, very good results have been obtained. In the
present study, a model for predicting compressive strength of SCC
containing various proportions of fly ash, as partial replacement of
cement has been developed by using Fuzzy Inference System (FIS).
For the purpose of building this model, a database of experimental
data were gathered from the literature and used for training and
testing the model. The used data as the inputs of fuzzy logic models
are arranged in a format of five parameters that cover the total binder
content, fly ash replacement percentage, water content,
superplasticizer and age of specimens. The training and testing results
in the fuzzy logic model have shown a strong potential for predicting
the compressive strength of SCC containing fly ash in the considered
range.
Abstract: Bamboo is extensively used in construction industry.
Low durability of bamboo due to fungus infestation and termites
attack under storage puts certain constrains for it usage as modern
structural material. Looking at many chemical formulations for
bamboo treatment leading to severe harmful environment effects,
research on eco-friendly preservatives for bamboo treatment has been
initiated world-over. In the present studies, eco-friendly preservative
for bamboo treatment has been developed. To validate its application
for structural purposes, investigation of effect of treatment on
compressive strength has been investigated. Neemoil (25%)
integrated with copper naphthenate (0.3%) on dilution with kerosene
oil impregnated into bamboo culm at 2 bar pressure, has shown
weight loss of only 3.15% in soil block analysis method. The results
from compressive strength analysis using HEICO Automatic
Compression Testing Machine reveal that preservative treatment has
not altered the structural properties of bamboo culms. Compressive
strength of control (11.72 N/mm2) and above treated samples (11.71
N/mm2) was found to be comparable.
Abstract: Off-site construction methods have played an
important role in the construction sector in the past few decades. It is
increasingly becoming a major alternative technique and strategic
direction compared to traditional in-situ method. It produces a
significant amount of value for the construction industry and the
economy more generally. To date, an impressive number of studies
have been lunched on the perceived perception of off-site
construction. However, it seems that a quantifying benefit on the
offsite construction area is lacking. Therefore, this paper examines
the recent research literature on the benefits of off- site construction
and provides future direction. In the beginning, this paper provides a
brief history and current value of the off-site construction followed
by a detailed discussion on the benefit of off-site construction. These
benefits include but not limited to time saving, quality improvement,
relieving skills shortages, cost reduction and productivity
improvement. Toward this end, off-site construction should learn
from other productive industry similar to services or manufacturing
industry by applying operational management tools and techniques
with extensive focus on employee empowerment will shed the light
on future uptake of Off-site construction. This study is of value in
providing scholars have a clear picture of perceived benefit of off-site
construction research and give an opportunities for future uptake of
off-site method.
Abstract: This research paper aims to identify, analyze and rank
factors affecting labor productivity in Spain with respect to their
relative importance. Using a selected set of 35 factors, a structured
questionnaire survey was utilized as the method to collect data from
companies. Target population is comprised by a random
representative sample of practitioners related with the Spanish
construction industry. Findings reveal the top five ranked factors are
as follows: (1) shortage or late supply of materials; (2) clarity of the
drawings and project documents; (3) clear and daily task assignment;
(4) tools or equipment shortages; (5) level of skill and experience of
laborers. Additionally, this research also pretends to provide simple
and comprehensive recommendations so that they could be
implemented by construction managers for an effective management
of construction labor forces.
Abstract: As Malaysia aims to be a developed country by year 2020; the construction industry has since been identified as a major catalyst for the country to attain the status. It is one of the sectors that contribute to most environmental pollutions. It is, therefore, important for the industry to implement sustainable construction practices to reduce the negative impacts that it has on the environment. However, most Malaysian developers have placed much focus on market demand and economic factors; neglecting the need for attention on environmental issues. The practice of sustainable construction is deemed to be an obstacle to achieve short-term economic goals due to the higher cost incurred in the operations. Hence, choices need to be made and a balance needs to be struck in weighing the long-term environmental benefits against immediate economic factors. This paper discusses the challenges faced by Malaysian developers in adopting sustainable practices in the construction industry and the cause of these challenges. It also looks into the achievements and breakthroughs that developers in Malaysia have achieved so far. The paper aims explores the long-term benefits of sustainable practices that would potentially raise awareness on the feasibility and economic potential of sustainable construction.
Abstract: Sustainability, being the urgent issue of our time, is
closely related with the innovations in technology. Nanotechnology
(NT), although not a new science, can be regarded relatively a new
science for buildings with brand new materials and applications. This
paper tends to give a research review of current and near future
applications of nanotechnology (NT) for achieving high-performance
and healthy buildings for a sustainable future. In the introduction, the
driving forces for the sustainability of construction industry are
explained. Then, the term NT is defined, and significance of
innovations in NT for a sustainable construction industry is revealed.
After presenting the application areas of NT and nanomaterials for
buildings with a number of cases, challenges in the adoption of this
technology are put forward, and finally the impacts of nanoparticles
and nanomaterials on human health and environment are discussed.
Abstract: Self-Consolidating Concrete (SCC) is considered as a relatively new technology created as an effective solution to problems associated with low quality consolidation. A SCC mix is defined as successful if it flows freely and cohesively without the intervention of mechanical compaction. The construction industry is showing high tendency to use SCC in many contemporary projects to benefit from the various advantages offered by this technology.
At this point, a main question is raised regarding the effect of enhanced fluidity of SCC on the structural behavior of high strength self-consolidating reinforced concrete.
A three phase research program was conducted at the American University of Beirut (AUB) to address this concern. The first two phases consisted of comparative studies conducted on concrete and mortar mixes prepared with second generation Sulphonated Naphtalene-based superplasticizer (SNF) or third generation Polycarboxylate Ethers-based superplasticizer (PCE). The third phase of the research program investigates and compares the structural performance of high strength reinforced concrete beam specimens prepared with two different generations of superplasticizers that formed the unique variable between the concrete mixes. The beams were designed to test and exhibit flexure, shear, or bond splitting failure.
The outcomes of the experimental work revealed comparable resistance of beam specimens cast using self-compacting concrete and conventional vibrated concrete. The dissimilarities in the experimental values between the SCC and the control VC beams were minimal, leading to a conclusion, that the high consistency of SCC has little effect on the flexural, shear and bond strengths of concrete members.
Abstract: Construction industry in Greece consumes annually
more than 25 million tons of natural aggregates originating mainly
from quarries. At the same time, more than 2 million tons of
construction and demolition waste are deposited every year, usually
without control, therefore increasing the environmental impact of this
sector. A potential alternative for saving natural resources and
minimize landfilling, could be the recycling and re-use of Concrete
and Demolition Waste (CDW) in concrete production. Moreover, in
order to conform to the European legislation, Greece is obliged to
recycle non-hazardous construction and demolition waste to a
minimum of 70% by 2020. In this paper characterization of recycled
materials - commercially and laboratory produced, coarse and fine,
Recycled Concrete Aggregates (RCA) - has been performed. Namely,
X-Ray Fluorescence and X-ray diffraction (XRD) analysis were used
for chemical and mineralogical analysis respectively. Physical
properties such as particle density, water absorption, sand equivalent
and resistance to fragmentation were also determined. This study,
first time made in Greece, aims at outlining the differences between
RCA and natural aggregates and evaluating their possible influence
in concrete performance. Results indicate that RCA’s chemical
composition is enriched in Si, Al, and alkali oxides compared to
natural aggregates. X-ray diffraction (XRD) analyses results
indicated the presence of calcite, quartz and minor peaks of mica and
feldspars. From all the evaluated physical properties of coarse RCA,
only water absorption and resistance to fragmentation seem to have a
direct influence on the properties of concrete. Low Sand Equivalent
and significantly high water absorption values indicate that fine
fractions of RCA cannot be used for concrete production unless
further processed. Chemical properties of RCA in terms of water
soluble ions are similar to those of natural aggregates. Four different
concrete mixtures were produced and examined, replacing natural
coarse aggregates with RCA by a ratio of 0%, 25%, 50% and 75%
respectively. Results indicate that concrete mixtures containing
recycled concrete aggregates have a minor deterioration of their
properties (3-9% lower compression strength at 28 days) compared to
conventional concrete containing the same cement quantity.
Abstract: Preference for different conflict resolution styles is
influenced by cultural background and power distance of two parties
involving in conflict. This research put forward 7 hypotheses and
tested the preference differences of the five conflict resolution styles
between Chinese owner and contractor as well as the preference
differences concerning the same style between two parties. The
research sample includes 202 practitioners from construction
enterprises in mainland China. Research result found that theories
concerning conflict resolution styles could be applied in the Chinese
construction industry. Some results of this research were not in line
with former research, and this research also gave explanation to the
differences from the characteristics of construction projects. Based on
the findings, certain suggestions were made to serve as a guidance for
managers to choose appropriate conflict resolution styles for a better
handling of conflict.
Abstract: The construction industry is turning towards sustainability. It is a well-known fact that sustainability is based on a balance between environmental, social and economic aspects. In order to achieve sustainability efficiently, these three criteria should be taken into account in the initial project phases, since that is when a project can be influenced most effectively. Thus the aim must be to integrate important tools like BIM and LCA at an early stage in order to make full use of their potential. With the synergies resulting from the integration of BIM and LCA, a wider approach to sustainability becomes possible, covering the three pillars of sustainability.
Abstract: This paper presents a study on use of alkali activated bottom ash (BA) and ground granulated blast furnace slag (GGBS) blend in paver blocks. A preliminary effort on alkali-activated bottom ash, blast furnace slag based geopolymer (BA-GGBS-GP) mortar with river sand was carried out to identify the suitable mix for paver block. Several mixes were proposed based on the combination of BA-GGBS. The percentage ratio of BA: GGBS was selected as 100:0, 75:25, 50:50, 25:75 and 0:100 for the source material. Sodium based alkaline activators were used for activation. The molarity of NaOH was considered as 8M. The molar ratio of SiO2 to Na2O was varied from 1 to 4. Two curing mode such as ambient and steam curing 60°C for 24 hours were selected. The properties of paver block such as compressive strength split tensile strength, flexural strength and water absorption were evaluated as per IS15658:2006. Based on the preliminary study on BA-GGBS-GP mortar, the combinations of 25% BA with 75% GGBS mix for M30 and 75% BA with 25% GGBS mix for M35 grade were identified for paver block. Test results shows that the combination of BA-GGBS geopolymer paver blocks attained remarkable compressive strength under steam curing as well as in ambient mode at 3 days. It is noteworthy to know BA-GGBS-GP has promising future in the construction industry.
Abstract: Excavators are high power machines used in the mining, agricultural and construction industry whose principal functions are digging (material removing), ground leveling and material transport operations. During the digging task there are certain unknown forces exerted by the bucket on the soil and the digging operation is repetitive in nature. Automation of the digging task can be performed by an automatically controlled excavator system, which is not only control the forces but also follow the planned digging trajectories. To develop such a controller for automated excavation, it is required to develop a dynamic model to describe the behavior of the control system during digging operation and motion of excavator with time. The presented work described a dynamic model needed for controller design and which is derived by applying Lagrange-Euler approach. The developed dynamic model is intended for further development of an automated excavation control system for light duty construction work and can be applied for heavy duty or all types of backhoe excavators.
Abstract: Development in construction industry is leading to involve complexities in engineering systems; whereas it also required to its sustainability towards social, environmental, and economical aspects. Experts with requisite background and expertise are involved in order to integrate knowledge in achieving whole criteria through design process. Collaborative design is needed in order to attain optimum design through shared solution and goal from experts. This study is conducted to explore issues and approaches development of collaborative design research in construction and its influence to sustainability of the development. Literature review method is used in order to conceptually figure future research direction of collaborative design research. This research is a part of beginning process in doctoral research program, and will be used to support dissertation’s conceptual definition.
Abstract: The construction industry is a very dynamic field. Every day new technologies and methods are developed to fasten the process and increase its efficiency. Hence, if a project uses fewer resources it will be more efficient.
This paper examines the recycling of concrete construction and demolition (C&D) waste to reuse it as aggregates in on-site applications for construction projects in Egypt and possibly in the Middle East. The study focuses on a stationary plant setting. The machinery set-up used in the plant is analyzed technically and financially.
The findings are gathered and grouped to obtain a comprehensive cost-benefit financial model to demonstrate the feasibility of establishing and operating a concrete recycling plant. Furthermore, a detailed business plan including the time and hierarchy is proposed.
Abstract: The construction sector constitutes one of the most important sectors in the economy of any country. Contractor selection is a critical decision that is undertaken by client organizations and is central to the success of any construction project. Contractor selection (CS) is a process which involves investigating, screening and determining whether candidate contractors have the technical and financial capability to be accepted to formally tender for construction work. The process should be conducted prior to the award of contract, characterized by many factors such as: contactor’s skills, experience on similar projects, track- record in the industry, and financial stability. However, this paper evaluates the current state of knowledge in relation to contractor selection process and demonstrates the findings from the analysis of the data collected from the Delphi questionnaire survey. The survey was conducted with a group of 12 experts working in the Libyan construction industry (LCI). The paper starts by briefly explaining the general outline of the questionnaire including the survey participation rate, the different fields the experts came from, and the business titles of the participants. Then the paper describes the tests used to determine when the experts had reached consensus. The paper is based on research which aims to develop rank contractor selection criteria with specific application to make construction projects in the Libyan context. The findings of this study will be utilized to establish the scope of work that will be used as part of a PhD research.
Abstract: The population growth in the world requires an increase in demand of residential and housing construction. Using lightweight construction materials such as cold formed steel sections and ferrocement could be an alternate solution to foster the construction industry. In this study, a new composite column is introduced. It consists of cold formed steel section and ferrocement jacket. The ferrocement jacket was constructed using self-compacting mortar with two wire steel mesh of 550 MPa yield strength. Experimental push out tests was conducted to investigate the strength capacities and behavior of proposed shear connectors namely, bolt, bar-angle and self-drilling screw shear connectors. It was found that bolt connector showed the best behavior followed by bar-angle. Also, it was concluded that the ferrocement could be used to strength and improve the behavior of cold formed steel column.
Abstract: Delay can be defined as time overrun or extension of time to complete the project. There are high possibilities that delay issues in final account closing cannot be avoided especially in construction project in Malaysia which is unique and dynamic in the terms of nature of design and technical skill. Delay in final account closing is a situation when the actual planning (time and budget allocation) of a construction project exceeds the planned schedule or on the other hand, final account closing exceeds the time and other provisions specified in the contract. The causes of delay discussed in this paper are appraised from the literature review. There are two main types of delay: excusable delay and non-excusable delay. The literature reviews on the delay in final account closing which is then translated into a theoretical framework are summarized in the context of construction players and academician perspective. It is anticipated that the finding reported in this paper could assist the planning of future strategies and guidelines of final account closing for the betterment of construction projects in Malaysia.
Abstract: Construction industry is considered as one of the main contributor of natural resources depletion, responsible for high level pollution and it is one of the attributes that pose climate changes and other environmental threats. A lot of efforts had and have been done to reduce and control these impacts. Project Environmental Management (PEM) includes the processes required to ensure that the impacts of the project execution to the surrounding environment will remain within the limits stated in legal permits. The main aim of most of researches conducted managing Environmental Impacts (EI) is to protect earth planet from pollution. Those researches are presenting four major environmental elements; Environmental Management Systems (EMS), Environmental Design (ED), Environmental Planning (EP) and Environmental Impacts Assessments (EIA). Although everything has been said about environmental management for construction projects, but almost everything remains to be said and therefore to be explored or rediscovered because incontestably, almost everything remains to be done. This paper aimed at reviewing some of what has been said about PEM. Also one of its objectives is to explore and rediscover the whole view of managing the EI problems by proposing a framework that based on the relation between these environmental researches.