Flexibility in Construction Building Structures-A Case Study

Buildings are generally heavy, fixed, and normally irreversible once construction has been completed. Due to changing demands of the occupants, they may confront the need for future expansion or complete changeover. Due to economic-based irreversibility, the expansion or conversion of a constructed building requires the foundation and columns to be enhanced and such options for expansion or conversion are planned at the very beginning of construction. Enhancing the foundation and columns represents an up-front cost, but has a return in flexibility for future expansion. This trade-off can be viewed as an investment problem, in that a premium has to be paid first for an option that can be exercised later. An optimum choice is required to be taken for foundations versus flexibility trade-off in order to balance the expected profits that may arise from future expansion, i.e., the value of flexibility, and the cost of enhancing the foundation. The authors in this paper explain a case of an educational institution in order to show the value of flexibility. The value of flexibility in this case study is so significant that failure to account for flexibility is not economical. *Corresponding author: Rashmi Shahu, Shri Ramdeobaba College of Engineering and Management (RCOEM), Nagpur, India, Tel: +917122580011; E-mail: rashmishahu17@gmail.com Received August 28, 2017; Accepted September 06, 2017; Published September 13, 2017 Citation: Shahu R (2017) Flexibility in Construction Building Structures A Case Study. Ind Eng Manage 6: 229. doi:10.4172/2169-0316.1000229 Copyright: © 2017 Shahu R. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Introduction
There is some or the other uniqueness in each construction project due to which change in the construction process is inevitable on most construction projects. Change is defined as any event or situations that results in a modification or alterations of the original scope, execution time, or cost of work [1]. Such changes occur on a project for many reasons, such as design errors, design changes, additions to the scope, or unknown conditions. Each such change has a high impact on the original cost and schedule of the project [1]. In most of the industries where there is a stable environment the changes are predictable and are not frequent. Due to which the critical variables can be identified and a plan can be developed for the same. However, in extremely turbulent and dynamic environments like construction industry where change is frequent and unpredictable, it becomes difficult to go through the routine process and follow the plan. Hence flexibility becomes inevitable for such environments [2]. The present study explores the scope of structural design characteristics of building (flexible building structure) that can make the renovation work much easy and relatively less costly. The study uses 3 major renovation cases of old educational building projects for exploring the scope of design flexibility in building structures.

Literature Review
There is a huge mismatch between what the occupant requirement is and how the building is functioning. Most of the large construction projects are planned at least 5-6 years in advance. During this time, demands on the infrastructure are likely to change significantly. Changing demands may result from new forms of construction technology, changes in government regulations, change of rules in funding agencies, etc. There are many key stakeholders who are directly linked with a construction projects like project owners, users, project management, architects, consultants, and contractors. With so many stakeholders playing a key role there is scope of frequent changes in the requirements of each stakeholder. This creates a need of flexibility in the construction projects [3]. It has been observed that a very little thought has been given on the design of flexible building structure to meet future requirement. The building developers do not want to invest for attaining future flexibility of buildings, particularly when the future requirement is not known [4]. In the present dynamic society where the occupants requirement are changing very fast, the buildings need to be design so as to adapt to the changing needs of its occupants. It has been observed that in order to cater to the occupant's requirements, relatively young buildings (10-25 years old) are demolished. For a ready adaptation to market fluctuations it would be good to impose the condition that the building, along with its installations should be suitable for several uses [5]. This is not a desirable situation in terms of investment, waste production, energy, materials and sustainability of building [6]. There is a need to increase the functional life span of building which could be achieved if the buildings could easily be adapted to new occupant requirements [7]. It is therefore important to look at buildings from a broader perspective than just the first occupant requirements. "Flexibility can be defined as the ability to change or react with little penalty time, effort, cost or performance" [8].
Flexibility is a property of a building that is realized to some extent in all projects, even if it had not been actually taken into account in during the design phase. There are certain design characteristics of building which makes it feasible for a building for renovation work. There is a need to understand these design characteristics in order to save the future renovation cost. The projects in which there was a scope of flexibility in process, decision making, design, etc. showed higher level of success rate as compared to the projects with rigid system [9].

Method
A case study approach was used in this study to explore the scope of flexibility in design structures that makes renovation work easy. 3 major cases of renovation of old educational buildings were studied. The description of which is given below.

Flexibility in design:
There was a column beam frame structure constructed 27 years before, which proved to be supportive. So, for expansion there was no requirement for additional cost for foundation (Figures 1-4).
The first year bock was built with a foresight of expansion at that time laying additional cost for making the foundations and columns strong. Thus, leaving a scope of flexibility for future expansion.
The additional floor is constructed same as the second floor hence no chance to modify the architectural parameter of the building. While going on the construction of the building all management parameter is consider by the management like safety, construction activity etc.

Flexibility in design:
There was a column beam frame structure constructed 27 years before, which proved to be supportive. For additional floor it was required to give the additional treatment support of column from outer periphery of the building wherever necessary as consulted by the structural engineer hence additional cost was required to make this strategy (Figures 6-9).
The additional floor is constructed same as the second floor hence no chance to modify the architectural parameter of the building. While going on the construction of the building all management parameter is consider by the management like safety, construction activity etc.     The total construction cost=9576400+1950000=11526400.

Case 3
Location: Shri Ramdeobaba College of Engineering and Management, Katol Road, Nagpur.
Building name: Civil dept. block.

Literature:
The Civil block built in 1984 with G+2 floor. Civil block architectural and structural planning was carried out by considering the future vertical expansion of building. Hence additional foundation cost was laid in the year 1984 but construction was carried only up to second floor. The following are the plans of the building.

Flexibility in design:
There was a column beam frame structure constructed 27 years before, which proved to be supportive for additional floor (Figures 11-14).
The civil block was built with a foresight of expansion at that time laying additional cost for making the foundations and columns. Thus, leaving a scope of flexibility for future expansion.

Case Interpretation
The careful analysis of the three cases shows that:

Case 1
The additional investment for expansion was done in 1984 of Rs. 72533.24/-which proved to be beneficial at the time of expansion in 2005 with no additional treatment cost required.

Case 2
There was no scope left for expansion at the time of initial construction and hence the treatment cost required for expansion was Rs. 1950000/-.  The additional investment for expansion was done in 1984 of Rs. 56855/-but no expansion is done till date.
After a careful analysis of the three major cases it was observed that it is much beneficial to leave a scope of expansion or change by investing additional cost at the time of initial construction rather than incurring heavy treatment cost later. Even though no expansion is required later the additional investment is negligible as compared to the heavy treatment cost.

Result and Conclusion
The extra investment done to leave the scope of flexibility for building is much lower than the cost of expansion in case of building where there was no scope for expansion.
Bringing flexibility in projects involves costs as well as benefits. The cost of applying flexibility is much lower as compared to cost of managing unexpected changes. Hence it is better to make arrangements for flexible approach rather than dealing with changes on time. For having a proper flexible management it is necessary to identify the parts of the project where flexibility can be applied with little or no penalty costs on projects. While some researchers consider that bringing flexibility in projects will increase costs, cause delays of projects and thus will hamper the efficiency of projects, but looking at the long term goals, flexibility can be seen as adding value to the projects by improving on the overall effectiveness of projects and customer satisfaction.