Paper tries to list out the objectives, role and importance of mechanised construction in the built environment to achieve economy, efficiency, quality, cost-efficiency besides controlling time over run and cost over run.

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Mechanized Construction- Relevance and
Importance in India
* J.K. Gupta
** Amanjeet Kaur
INTRODUCTION
With globalization, liberalization and opening of the economy, India has been
experiencing major transformation in both physical and economic terms. With
technology and knowledge as major drivers of Indian economy, human
settlements in general and urban settlements in particular are fast emerging as hub
of economic activities and generators of employment. Large scale migration has
accordingly being witnessed in the urban sector. In order to meet the growing
needs of built space / infrastructure for the rapidly increasingly population, large
scale construction has been taking place in the country. With traditional and
outdated methods used for construction, most of the built
environment/infrastructures created in the process are cost and material intensive,
energy inefficient and largely responsible for project delays and cost over runs.
Massive population growth, rapid migration and ever increasing industrialization/
urbanization have been demanding cost effective, energy efficient and disaster
resistance structures. In order to provide affordable, environmentally sustainable
and state of art built environment, appropriate technology driven solutions will
have to be put in place. Various options will have to be explored which would
increase the speed of construction without compromising with the quality,
minimize time span of the projects, reduces the project cost and wastage of
materials besides making optimum use of available resources and materials
through innovative and latest technologies. In search of such solutions, we have
to critically look at the options provided in terms of use of mechanized
construction utilizing the modern materials and technologies, standardization of
various structural and non-structural building components, training people
involved in construction industry and developing techniques to improve/upgrade
the traditional materials and technologies.
INDIAN CONTEXT
Rapid growth of Indian economy has led to the emergence of construction as the
second largest industry in the country after agriculture, making significant
contribution to the national economy and generating large scale employment. The
use of state of art technologies and deployment of project management strategies
has made it possible to undertake construction projects at mega scale. With
exponential growth brought in by IT and ITES, the cities are being gripped by
feverish construction activity and land development. The skylines of our towns
are witnessing a veritable burgeoning dotted with tall buildings in all the sectors.

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The economic boom India is witnessing requires adequate support and backing
from services and manufacturing industry to sustain and accelerate it. Strategy
should focus on building industry and promoting planned development in order to
strike a balance between built and open space and creation of quality living for
majority of urban inhabitants rather than cursing urbanization.
CONSTRUCTION INDUSTRY AND NATIONAL ECONOMY
Looking at the current economic scenario of India and its economy, it is said that
current annual budget of India is placed at Rs.438,795 Crores against the total
Gross National Product (GNP) of about Rs.2200,000 Crores or more
(www.indiabudget.nic.in, 2004) with more than half of the expenditure made on
civil engineering works. Accordingly, the construction industry has emerged as
the prime mover of economical growth and development in the country.
Investment in this sector alone contributes 6.5% of Gross Domestic Product
(GDP) (Das, 2003). It is said that every Rupee invested in the construction
industry causes an increment of Rs.0.80 in GDP as against Rs.0.20 and Rs.0.14
made in the case of agriculture and manufacturing industry, respectively.
Statistics over the period have shown that compared to other sectors, this sector of
economy creates 4.7 times increase in incomes and 7.76 times increase in
employment generation. Sustained efforts by the Indian construction industry and
the Planning Commission have led to assigning the status of industry to
construction sector. With about 31 million persons employed in building industry,
formal and above board financial planning would be the obvious destination of
the construction sector in the country in order to achieved rapid growth, create
cost-effective, sustainable and energy efficient buildings.
PRESENT STATUS OF MECHANIZED CONSTRUCTION IN INDIA
Indian construction industry has suffered enormously and continues to suffer due
to use of outdated technologies and non-implementation of modern and
mechanized construction methodologies. Innovative practices have been adopted
as an exception rather than rule in few selected special and high budget structures.
Therefore, their use cannot be publicized. But these days the increasing load on
the building industry and feverish construction activities demand the adoption of
mechanized construction processes. The commonly used practices which can help
India to accelerate the construction processes include use of Ready Mix Concrete
(RMC), Pre Fabricated Components, Equipment Banks, Advance Training of
Labour, Project Management, Project Programming and Building Design with the
help of latest software’s and use of information technology. All of these practices
direct us towards making the construction industry modern and innovative.
However, recent times have seen the use of mechanized practices in the building
construction industry. Some of the mechanized practices already adopted in our
country include:
1. Project Management
2. Use of Prefabricated Components

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3. Use of Computer based technologies and IT in planning and conceptualization
4. Pre-Engineered Buildings
5. New and Hybrid Materials involving concrete, glass, steel components etc.
Project Management
There are large numbers of stakeholders in the process of planning, designing,
financing, constructing and operating physical facilities. They all have different
stakes and perspective on project management involving construction. Therefore,
specialized knowledge related to project management can be highly beneficial,
particularly in large and complicated projects for achieving the desired results, since
experts in various specialties can render valuable services. Waste, excessive cost and
delays can result from poor coordination and communication among specialists. It is
particularly in the interest of owners to ensure that such problems do not occur. If
attention is focused on the process of project management involving construction
then to be sure, each specialty has to make important contribution in developing new
techniques and tools for efficient implementation of construction projects. However,
it is through the understanding of the entire gamut of project management that these
specialists can respond more effectively in providing, marketing their specialties and
in improving the productivity and quality of their work.
Cost Management
Managing construction cost within the defined project budget outlay, plays a critical
role in achieving the three cardinal goals of project management i.e., cost within
budget, schedule on time, and quality as specified. In order to limit the construction
Fig. 1 Building components located in position with the
help of Crane
Fig. 2 Vertical transportation of material with the help of
machines

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cost within the specified budget, accurate and reliable cost estimations would be
critical throughout the project lifecycle. There have been three broad categories of
estimations widely utilized in the area of construction management depending on the
available information and required accuracy as defined below:
* Magnitude Estimation—This estimation is based on hypothetical design
information and minimum site information. It has the lowest level of accuracy and
reliability.
* Conceptual Estimation—Primitive design and construction site information are
the basis for formulating Conceptual Estimation. Depending upon the reliability of
the information available estimation has low to high level of accuracy.
* Detail Estimation—This estimation is based on complete project design,
specification, and environmental information and accordingly has highest level of
accuracy.
The detailed and accurate estimation, can be made when the detailed designs are
available. It is not feasible in the early stages of a project, such as the conceptualizing
and planning stages. As a result, the conceptual estimating methods are often adopted
for most of the projects for working out the estimate. The conceptual cost estimation
during engineering planning is the most critical for a construction project, since the
main structural systems, major construction methods and most construction materials
are determined at that stage. However, due to the lack of detailed design information
during the planning phase, the accurate cost estimation becomes a difficult task for
professional estimators. It has been observed that the estimators has a critical role in
determining the accuracy of project estimate and estimators with more estimating
experience can do better job of preparing cost estimates.
Prefabricated Components & Techniques:
Prefabrication has been the latest addition to the domain of mechanized constructions.
Looking at the complexity of the building construction projects and time/cost over
runs prefabrications offers numerous inherent advantages meeting all stringent
requirements related to areas of design, manufacture, transport and installation in
terms of:
• Achieving Precision
• Promoting Efficiently
• Over coming Scheduling constraints
• Ensuring Fire protection
• Achieving Durability

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• Ensuring Sound insulation
• Promoting Functionality
Architects, qualified design engineers and structural engineers guarantee practical and
economical designs – from planning, designing , construction and production. If
properly trained and educated, they can guide the construction process and ensure
Internet
The most dramatic new technology applied to construction has been the use of
Internet and its private, corporate Intranet versions. The Internet is widely used as a
means to foster collaboration among professionals working on a project, to
communicate for bids and results, and to procure necessary goods and services. Real
time video from specific construction sites is widely used to illustrate construction
progress to interested parties and its effective monitoring. The result has been more
effective collaboration, better communication and easy procurement.
Impact on Society
Impact of many new technologies on construction costs have been mixed because of
the high development costs involved in the use of new technologies. However, it has
been well accepted fact that design professionals and construction contractors who
have not adapted the latest technologies have gone out of the mainstream of design
and construction activities. Construction quality can be improved and construction
cost can be reduced with the adoption of new technologies which have already
proved their efficiency in the context of both performance and economy. However,
there appears to be inherent reluctance on the part of stakeholders involved in the
construction to accept latest technologies. Widespread public attitude representing
considerable skepticism about the external benefits and costs which new facilities
impose have been found to be major drivers to non acceptance of such technologies.
Fig. 4 Machine for mixing cement, fine and coarse aggregate
in desired ratio

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It is this attitude which is likely to make public scrutiny and regulation a continuing
concern for the construction industry looking for improvement and efficiency.
Pre-Engineered Buildings
These are special class of buildings, which are constructed by assembling pre-built
primary framing systems with other secondary structures and claddings. Various
types of framing systems such as clear span rigid frames, beam and column frames,
space saver frames, single slope; multi-span and lean-to frames are available
depending upon the needs of the builders. They are also built to accommodate various
sidewall heights, bay spacing’s and loading conditions. The invention of these
buildings has greatly increased the speed of construction. However, concerns have
been expressed over the multi-disaster resistance of these buildings. Hence, full scale
testing should be conducted on them especially on their connections to confirm their
reliability in sustaining hazards.
FUTURE OF MECHANISED CONSTRUCTION PROCESSES
USE OF ARTIFICIAL INTELLIGENCE IN PROJECT MANAGEMENT
With the development of modern artificial intelligence (AI) techniques such as
neuron-fuzzy systems, the aforementioned estimating experience (knowledge) can be
acquired by learning from historical examples, so that accurate estimation (compared
with the detail estimation) could be obtained with limited available information
Unfortunately, an essential difficulty which faces the traditional conceptual cost
estimation is the large variation of the unit prices of the cost items in the
marketplace. In that case the estimation knowledge learned previously may not be of
much relevance and readily applicable in the future projects.
According to past experience, the applications of knowledge-based systems in the
fields of construction engineering and management confront a major problem—
Fig. 5 Present construction trends in Building Industry

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updating of the knowledge base and maintenance of software systems. In such cases
providing the easiest accessing means is the best way to avoid use of absolute and
out-dated information.
PRINCIPAL ITEMS RATIO ESTIMATION METHOD (PIREM)
Among the many conceptual estimating methods, parametric cost estimating has been
widely applied in the industry for economic feasibility analysis in the early stage of a
construction project. The parametric cost estimating takes critical parameters as
inputs, such as the floor area, cubic volume, bay width, etc. By using statistic
regression or other mapping schemes, the relations between the estimated costs and
the influential parameters are established. The cost estimates of new projects are
obtained by mapping inputs of parameter values based on the pre-determined
mathematical relation.
Model of PIREM
With the effective use of Pareto Optimum Criterion, almost 80% of estimation cost
and time can be saved. Thus, it does not only reduce the cost but also expedite the
process of estimation, and more importantly provide a feasible solution for real-time
cost estimation. The selected top 20% cost items is called “Principal Items (PI)”. The
summation of quantities and unit prices of the principal cost items constitutes the
Cost of Principal Items (PIC).
The PIREM method separates unit price from the quantity of a cost item, so that the
current unit market price can be reflected in the estimation results. Detailed
verification and testing of the proposed system are conducted to ensure the
performance of the system and its successful application to the industry. It is found
that the proposed WICE not only achieves a higher accuracy than any existing
conceptual estimation systems, but also provides a globally and all-time accessible
system so that real-time cost estimation becomes possible. Moreover, the centralized
knowledge base maintenance and management of WICE guarantee the users with the
most updated cost estimation knowledge. Qualitative and quantitative analyses on the
benefits expected from WICE are also analyzed and discussed. Both of the analyses
show that significant benefits can result from WICE.
Future directions of web-based applications on construction engineering and
management may include business intelligence development for design, construction,
and management problems. Knowledge-based economy products generated from
historical data are worthy of follow-up research.
Closed Structurals
The structural and functional advantages of hollow sections have always appealed to
the engineers. Till 1959, square and rectangular hollow sections were shop fabricated
by welding or jointing together structural plates and sections. This involved expensive

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fabrication, restricting architectural expressions to traditional steel forms. Research
and development in the area of hollow sections is primarily carried out by an
international organization, CIDECT (Headquarters: Paris). In India, TATA STEEL
adopted this concept. The excellent distribution of the material around the centroidal
axis of closed structurals exhibits remarkable strength and thus offers decisive
advantages in its applications. Compared to conventional sections, hollow sections
result in reduced use of steel without compromising with their strength and
performance standards and are accordingly emerging as preferred materials for
mechanized construction.
Engineered Steel Guardrail Systems
A noticeable change in the construction projects is the quantitative design of systems
that were hitherto provided in a prescriptive way. The engineered steel guardrail
systems provide utmost safety for vehicles and pedestrians on roads, highways and
bridges. These rail systems are specially profiled with W- or 3-Beam systems. They
are manufactured using facilities such as high precision cold forming lines, large
presses, automated welding lines and complete in-house fabrication facilities ideally
suitable for manufacture of high quality steel guard systems. Mainly used as medians
and edges of highways and bridges, these systems are highly beneficial for promoting
mechanized construction because of their capability to:
(a) absorb large impact and minimum damage to the vehicle;
(b) restrain laterally the vehicle from veering off the carriageway;
(c) prevent vehicles from skidding back to the carriageway during impact;
(d) provide gradual deceleration of the vehicle into the carriageway after impact
minimizing any risk to flowing traffic;
(e) act as a visible guide to drivers during nights and in poor weather conditions; and
(f) permit quick repair in case of damage caused due to accident.
Urban Construction Strategies
For smoother flow of traffic, urban areas are having large scale construction projects
involving road network in terms of flyovers and under-passes on important roads.
Considering the importance of the roads, traffic connot be closed while the
construction process is in operation. In such cases, large-size pre-cast piers are used
in the construction of flyovers over existing roads or other utility services that are too
important to be closed or dismantled for the construction work of the flyovers These
massive precast structures are erected at site with large capacity cranes that are
themselves not to restrict the flow of traffic. In addition, the Indian Society of Trench
less Technology (INDSTT) introduced the trench-less pipe laying technology to assist
in interruption free construction in urban environments. Besides project design,
development, implementation and monitoring are gradually getting transferred to the
computers by consultants, project owners and contractors. Some leading corporate
agencies are planning initiatives for web-enabled design, control and monitoring of
construction projects.

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Machine Automated Slip-form Pavers
The hectic pace of construction of highways across the country and the extensive
work of flyovers in the urban areas, made it imperative to use mechanized methods of
pavement construction. The machines in use are equipped with guidance systems that
guide the pavers along the desired alignment of the pavement. These machines are
fitted with tilt sensors that deliver information about the longitudinal and transverse
slopes of the machines. Monitoring devices stationed on ground transmit a permanent
stream of measurements by radio to the machine's on-board PC. The PC uses this data
to calculate the current position of machines and its orientation and then compares it
with the project design. The resulting control parameters are then sent to the machine.
The guidance system continually matches instantaneous position with the desired
profile of the pavement, adjusting the height profile of the concrete as it is being laid
besides steering the machine in the required direction. This non-stop machine
guidance accomplishes greater speed and precision than would be possible with the
eye or conventional measurement and control techniques. With the machine
operatoring under automatic control, the driver can concentrate fully on the
production process. Better operational safety and reliability result in greater paving
speed and productivity.
NEW MATERIALS, EQUIPMENT AND TECHNOLOGIES
Manufacturing of new materials is going on at a more aggressive pace but the
manufacturing of new equipment is constrained by large capital investments and the
uncertain markets. However, the growing market for such advanced equipment will
eventually push the entrepreneurs to manufacture these equipment also. On the
technological front, the picture is abysmally low. The country has not invested
adequately into making technical human resources capable of addressing the
professional services needs of the construction industry like litigation, training of
artisans, cost indices, contracting, insurance, finance, banking and taxation. On the
engineering design front, the college education of the practicing engineers has not
been adequately augmented from time to time with introduction of latest in-house or
distance education modules. Thus, senior engineers are often found oblivious to new
technologies and mechanized tools. As a consequence, the country is faced with
acute shortage of technical manpower. The following are some of the newer
initiatives of the construction industry in the area of materials and construction
strategies.
Corrosion Resistant Steel (CRS)
This new-generation high strength ribbed reinforcement bar, was first introduced in
India by m/s TATA Steel Limited, Jamshedpur. It is different from traditional bars in
its method of manufacture and consequently in its properties. CRS is produced using
the Tempcore Process, introduced in India for the first time by TATA Steel under
license from Center de Rechaerche Metallurgiques (CRM), Belgium – inventors of

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the process. The process imparts high strength to the bar using the thermo mechanical
treatment (TMT) technique; this is in contrast to the cold twisting that was used in the
manufacture of traditional reinforcing bars. The cross-section of bars produced by this
treatment process has a strong outer layer of tempered martensite and a ductile inner
core of ferrite-pearlite. The duality in the constitution gives these bars their unique
combination of high strength and high ductility. These bars have additional desirable
properties: no residual stress, uniform properties along the length, high bond strength
(2-3 times that in mild steel bars), and superior bendability.
PRESENT SCENARIO OF FACTORY-BUILT COMPONENTS IN HOUSING
INDUSTRY IN USA
According to the recent trends, the Factory-built components demand is projected to
increase 5.3 percent per annum through 2006 to $16.9 billion. Growth will be driven
by the increased utilization of prefabricated components on a unit structure basis,
which will in turn be supported by the advantages in construction cycle time, cost and
product quality offered by the components relative to site-built construction methods.
Moreover, this pace will represent an improvement from the 1996-2001 periods based
on an anticipated recovery in the manufactured housing market major end users for
components.
• I-joists, walls/partitions to offer strong growth
Roof trusses have traditionally dominated prefabricated components, accounting
for over one-half of total production in 2001. However, future gains for roof
trusses will be limited after 2006 by the high market penetration levels already
achieved by the products, as the market is nearing saturation. Components such as
I-joists and prefabricated walls and partitions will offer much stronger growth
prospects.
• Prefabricated housing market to post double digit annual gains
The sheer size of the site-built housing market leads to site-built housing
dominating demand for prefabricated components. These applications accounted
for over four-fifths of total sales in 2001, and demand will rise @ of nearly four
percent per year through 2006. In contrast, demand for factory-built components
in prefabricated housing will show a significant improvement from the 1996-2001
periods with projected annual gains of over ten percent.
• Industry concentration
The factory-built housing component industry is highly fragmented, consisting of
thousands of companies, the majority of which are small, privately-held firms
operating in only a single product grouping or regional market. Industry leaders
are generally segmented along market lines, consisting of diversified building

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material suppliers that serve the site-built housing market and prefabricated
housing manufacturers that produce components for internal use.
Although it is generally believed that factory-built housing applies only to single-
family homes, a number of builders are realizing time, and in case of mass
housing cost savings with modular apartments. Modular multiple dwellings are
available as customized buildings that looks like site-built structures, assembled
in a factory while earthwork, foundations, and utilities are prepared onsite. The
scale and repetition that characterizes many multi-family buildings lends itself to
an automated solution, especially in areas located near the factories. The
controlled indoor environment and stable, experienced labor are conducive to
assemblies with consistent quality, often at reasonable cost. Workers familiar with
their product can more easily integrate unfamiliar materials and techniques with
other trades working side-by-side. Also, the rapid building cycle of modular
construction can reduce or eliminate jobsite and theft.
Modular apartment buildings first burst on the scene in the '60s with the
celebrated "Habitat" in Montreal, designed by architect Moshe Safdie. The costly
assembly of concrete cubes and terraces looks like an industrial-age
Mediterranean hill town. Today's modular multiple dwellings are less complex
and almost always wood framed, except for some companies which also frames
with steel or some which use steel exclusively. Modular multiple dwellings
consist of boxlike sections stacked vertically and horizontally with a crane. Each
box is approximately 14' wide by 50' long (this varies considerably), one-story
high, and includes all partitions between a fully-framed floor and ceiling.
Although companies accommodate various configurations, most are orders for
side-by-side duplexes in two-story attached townhouses. Other arrangements
include townhouse flats, duplexes over flats, and "quads" with two flats over two
flats. Less common are apartment buildings with shared entrance halls. Although
the design is standardized, it can be offered in a number of site-specific plans and
elevations. In many cases the buyer will order through an options/configuration
checklist categorized by trade.
CONCLUSION
TECHNICAL HUMAN RESOURCE and EMPLOYMENT POTENTIAL
In India, traditionally the construction industry has been labour intensive as the
labour is cheap and easily available. In 1995-96, approximately 1.50 Crores
people were employed in this industry which increased to be 3.26 Crores in the
year 2004-2005 (Das, 2003). There are three categories of manpower involved in
this industry consisting of the artisan level, the supervisory level and managerial
level. It has been observed that every Rs.1 Crore, investment on construction
project, generates employments of 22,000 unskilled man-days, 23,000 skilled or
semiskilled man-days and 9,000 managerial and technical man-days
approximately. With only 3% of total teaching in the country addressing the direct

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needs of the construction engineering and management aspects required in the
construction industry, the 14th
Engineering Congress on Human Capital
Development in January 2002 observed that “in time to come, India will not have
sufficient quality civil engineers even to undertake basic infrastructure work.”
Urgent steps are to be initiated to reverse this trend of severe shortage of technical
manpower.
THE CHALLENGES
The construction industry everywhere faces problems and challenges. However,
in developing countries like India, these difficulties and challenges are highly
pronounced alongside a general situation of socio-economic stress, chronic
resource shortages, institutional weaknesses and a general inability to deal with
the critical issues. There is also evidence that the problems have become greater
in extent and severity in recent years. One of the charges leveled at the
construction industry, as at the beginning of the 21st century, is that it has a poor
record on innovation, when compared with manufacturing industries such as
aerospace or electronics.
References:
• Material from net
• Civil Engineering and Construction Review
• Proceedings of the National Conference on “Infrastructure Development
in Civil Engineering” held in NIT, Hamirpur on 16-17 May, 2008.
• Proceedings of the National Conference on “Quality Reliability and
Maintainability Aspects in Engineering Systems” held in NIT, Hamirpur
on 27-28 December, 2007.
Authors
Ar. Jit Kumar Gupta Ar. Amanjeet Kaur
Director, College of Architecture, Lecturer, Deptt. of Architecture,
IET Bhaddal, P.O. Mianpur, (Ropar) (Punjab) NIT Hamirpur (H.P)

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