There are many factors that determine the
outcome of a project but the six main parameters that can sufficiently define a
construction project are size, complexity, quality, productivity, completion
time and cost.
· Size
denotes the number of tasks to be executed in a project and each task is
measured in terms of quantities of work involved.
· Complexity
is a measure of variety in the nature of tasks to be executed i.s. complexity
increases as the number of dissimilar task increase and it decreases if the
tasks are repetitive or similar in nature.
· Quality
to be achieved in accomplishing tasks is stated in terms of standard
specifications.
· Productivity,
in its broader sense, measures the ratio of planned effort to produce a unit
quantity of work divided by the actual effort employed to achieve this unit of
work.
· Completion
time depends upon the speed with which the project is to be executed.
· Cost
is the expenditure which the client has agreed to commit for creating the
desired construction facility.
The above six parameters are
interdependent and interactive, that is each parameter is a function of the
other. For example, consider the effect of repetition on completion time of a
project containing 12 tasks of specified quality and cost, with each taking a
unit time to execute. If there is no repetition of task, that is, if all the
tasks are dissimilar, sequential and are taken one at a time, the earliest
completion time for the project would be 12 units. But if four tasks can be
repeated, each three times, as shown in Fig. then the earliest completion time
would be six units.
With an increase in the repetition of
similar tasks, there is an improvement in resource productivity due to the
experience gained, which consequently results in reduced overall costs.
The evaluation of interrelationship among
the six project parameters is a complicated process. However, in a given
project, the scope of work in terms of size, repetition and quality gets
specified and these parameters thus can be treated as constants. Productivity
standards for each item of resources needed to execute a work in a given time
is estimated, and this forms the basis for determining the time and cost of the
project. The achievement of the two parameters, that of time and cost, depends
upon the effectiveness and efficiency with which the project resources are
managed.
The planning and controlling of the
project objectives of time and cost and setting up of the resources
productivity standards to achieve these objectives, are the most important
functions of the project management. The planning and controlling methodology
employed for this purpose is loosely called the ‘project management techniques’
.