SHRINKAGE AND CREEP BEHAVIOUR OF SLAG CEMENT CONCRETE
PROF. PAZHANI K. C. AND MR. CHANDRU N.
Large scale investments are witnessed recently in the infrastructure projects such as highways, road and railway bridges, airports etc. Most of the spending on these projects has been attributed to the cost of bulk materials like cement, steel and concrete. Any small breakthrough in the research and development in concrete will be cost effective as far as the materials are concerned. Cement production is one of vast potential damages of environment. Hence, it is necessary to replace cement with some alternates. Creep and shrinkage of concrete are known to have significant effects at early age of concrete. The strength and durability of concrete mainly depend on the shrinkage and creep of concrete. To predict the behavior in terms of strength and durability, it is essential to know the behavior of shrinkage and creep of the concrete at various ages. So, the current paper is aimed to study the behavior of creep and shrinkage of concrete at various ages with replacement to cement by slag and fly ash with different replacement levels.
Shrinkage, Creep, Slag Cement Concrete
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Research Articles
PROJECT SCHEDULING ANALYSIS AND QUANTIFYING RISK IN CONSTRUCTION DELAYS USING BAYESIAN BELIEF NETWORKS
PROF. K. R. SURESH AND MR. KISHORE R.
Project management techniques are widely used to plan, execute, control, and deliver construction projects. The goals of a successful project management endeavor are to finish on time, within budget and according to the specifications and quality standards. The ultimate benefit of implementing project management techniques is a satisfied customer. With higher requirements of quality, increasing demand for shorter project completion times and more efficient use of available budgets, project management professionals are facing the necessity of using analytical and quantitative tools that are more sophisticated than traditional qualitative approaches. Management of risks and uncertainties in construction projects is only possible if risks have been identified and the potential impacts have been analysed. Principles of probability theory offer the mathematical basis for modelling risks and uncertainty and the analysis of its effect. Construction schedules are affected by uncertainties in weather, productivity, design, scope, site conditions, soil properties, material delivery time, equipment efficiency, etc,.[18]. All risks in a construction project might be schedule risks because they are related to the schedule directly or indirectly. Moreover, all activities can be critical due to uncertainties, even those that are not critical according to deterministic Critical Path Method (CPM). Capturing uncertainty in projects 'needs to go beyond variability and available data'. It needs to address ambiguity and incorporate structure and knowledge. In order to measure and analyse uncertainty properly, one needs to model relations between trigger (source), risk and impacts (consequences). The duration of a task is uncertain because there is no similar experience before, so the data is incomplete and suffers from imprecision and inaccuracy. Estimation of this sort of uncertainty is mostly subjective and based on estimator judgment. Any estimation is conditionally dependent on some assumptions and conditions even if they are not mentioned explicitly. These assumptions and conditions are major sources of uncertainty and need to be addressed and handled explicitly. The most well established approach to handling uncertainty in these circumstances is Bayesian approach [9][12]. The present work is an attempt to identify the uncertainties in the construction project activity duration estimates of a construction project in Indian context and quantifying the risk involved in construction delays using Bayesian Belief Networks (BBN's).
Project Scheduling, Risk in Construction delays, Bayesian Belief Networks
(BBN's)
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Research Articles
ANALYSIS OF CONTRACT CLAUSES AFFECTING THE SCHEDULE PERFORMANCE OF A CONSTRUCTION PROJECT
MR. SYED TABISH, MR. S. A. H. PANDIAN AND DR. K. N. JHA
About one third of Indian Construction Projects are facing time over run ranging from 1 to 195 months. The delay in a project could be on account of several factors including poorly drafted contract clauses. Although a number of studies have been conducted to identify the factors causing time overrun very few studies have been conducted to identify and evaluate the contract clauses in general affecting the schedule performance of a construction project. As a case study, General Conditions of Contract (GCC) 2005 Form Central Public Works Department (CPWD) 7/8 is used for the study as most of the projects in India are being executed using this form. Through a two-stage questionnaire survey 16 clauses were found to have significant impact on schedule performance of a project. The factor analysis indicates 'determination of contract' clause as an important clause affecting the schedule performance of a project frequently besides payment and advances, deviations measures, schedule performance, and reimbursement of taxes related contract clauses. The results could help the professionals in focusing on key clauses affecting schedule performance of a project and modifying them to help projects achieve schedule and possibly budget goals.
Contract Conditions, Contract Drafting, India, Delay, Factor Analysis, Contract Clauses
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Research Articles
PROJECT DURATION CONTROLLING METHODS: AN EARNED VALUE
ANALYSIS APPROACH
PROF. JYOTI TRIVEDI AND MR. VARUN SHAH**
Earned value project management is a well-known management
system that integrates cost, schedule and technical performance.
It allows the calculation of cost and schedule variances and
performance indices and forecasts of project cost and schedule
duration. The earned value method provides early indications of
project performance to highlight the need for eventual corrective
action. Earned value management was originally developed for
cost management and has not widely been used for forecasting
project duration. However, recent research trends show an increase
of interest to use performance indicators for predicting total
project duration. Project management and its related processes are
the keys to staying organized and focused, and to accomplishing
the solutions a community needs after being hit by a disaster.
Reconstruction project management is about solving problems and
delivering intended results through an organized, structured methodology.
During execution of reconstruction projects many a time project
management methods and tools like earned value (cost loaded
schedule with focus on cost to complete) is missed out or not
taken into consideration thus, the study focuses on traditional
EVM methods compared with different methods to be used for
predicting project duration. It is very significant to complete any
task or project within planned time duration and cost. Schedule
variance is an important concept in EVM to monitor & control
actual work, but there are some criticisms associated with it. So
substitute methods have to be found out to control the project
duration, which can be effectively applied during execution of
project and will give us accurate result. The purpose of this paper
is to compare the classic earned value performance indicators SV
and SPI with the newly developed earned schedule performance
indicators SV(t) and SPI(t). Next objective is, to present a generic
schedule forecasting formula applicable in different project situations
and compare the three methods from literature to forecast total
project duration. Finally, application of the use of each method
on a simple real-life project data is presented.
STUDY ON FACTORS AFFECTING LABOUR PRODUCTIVITY IN THE
CONSTRUCTION INDUSTRY
PROF. S. KAMAL, DR. C. UMARANI AND MR. T. ANBU SELVARAJ
Productivity is one of the most important factors affecting the
overall performance of any organization. At the micro-level, improved
productivity decreases unit costs and serves as an indicator of the
project performance. At the macro-level, improved productivity is
a vital tool in countering inflationary effects and determining wage
policies. The efficiency and availability of materials along with the
effective labour productivity result in the best performance. The
productivity of individual workers or firms or industries differs
widely due to many numbers of factors which initiates a thorough
study of these factors both in terms of positive or negative
aspects. If all factors influencing the labour productivity are
known, it will be easier to forecast the productivity accordingly
and take necessary steps. This paper reports an empirical study
which applies the Delphi survey technique to formulate a model
to assess the productivity index. The survey is conducted and the
factors are ranked and out of these top six factors are chosen.
A formula for calculating the Labour Productivity Index (LPI) is
derived which can be used to find the productivity of a project.
LPI also broadens the existing knowledge of both academics and
practitioners in the construction industry because the research
method can be replicated in other geographical locations to create
similar indices for better understanding about various factors
affecting labour productivity at the global level.
Labour Productivity, Productivity Index, Construction Industry
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Research Articles
LITERATURE REVIEW OF FIELD DATA
BASED MATHEMATICAL
SIMULATION OF COMPLEX
CONSTRUCTION ACTIVITIES
Prof. S. P. Mishra, Dr. D. K. Parbat and Dr. J. P. Modak
The present article gives the detailed review
of the research papers published in the area
of mathematical simulation of construction
process by various researchers by adopting
different approaches. They include all modern
aspects in construction, but with respect
to Indian scenario where majority of total
construction works are still executed
manually and consume a lot of human energy
they need to be focused and develop a
mathematical relation which can simulate
the real input and output data directly from
the construction field where the work is
actually being executed. Here, the advantages
and limitations of the applied mathematical
models are identified and the models are
classified in terms of application range and
goals. The findings indicate that the topic
under study is of great importance as no
such approach of field data based
mathematical simulation is adopted where
human energy is related to productivity of
construction process.
Simulation, Construction Process, Ergonomics, Method Study, Human Factor, Work Station, Optimization, Anthropometry
Research & Publications Department 