A new paradigm for project
nothing is average!
Scheduling, Planning, Resource Optimisation, CPM, Flow Line, Critical
optimisation - a new paradigm for project scheduling [P152]
current focus of CPM scheduling on activities, sequences, float and
criticality is failing to deliver successful project outcomes. This
paper will look at the alternative approach based on workflows and the
optimisation of available resources; the underlying approach in
methodologies such as Flow-Line, ToC and Critical Chain (although non
of these methodologies use optimisation).
Current CPM scheduling is failing to deliver successful project
are two solutions to this problem, one is to move to a proper resource
optimisation approach (already included, in part, in tools such as
Spider) the second is to adopt a more pragmatic approach to scheduling
based on ‘what you know’.
project’s ignore the contract schedule (Glenwright: PM World
Today – August 2011)
of contract and penalty clauses don’t work (CIOB report)
project’s have shown no improvement in productivity for 40
years, the rest other industries have shown a 200% improvement (BSI
automatic resource levelling systems in most tools, most of the time,
produce sub-optimal results and changing a few settings in any of the
tools can produce wildly different outcomes.
The short-term pragmatic
A realistically achievable approach in the short term, can be
summarised as ‘plan what you
know and budget the rest’.
This is the
approach adopted in the CIOB ‘Guide
to good practice in the management
of time in Complex Projects’.
The Guide introduces the concept of
Density schedule is developed
and agreed with the client and
represents the contractual commitment to deliver the project.
more than 12 months in the future is planned at Low Density
and defines the long-term strategic commitments of the project
more than 3 months in the future is scheduled at Medium
Density and defines the
tactical approach to achieving the overall
strategy set out in the Low Density schedule.
in the near term is scheduled at High
and defines in
detail who will be doing what, where and when based on the resources
actually available and their measured productivity.
Density schedule is
developed and agreed with the key
suppliers and subcontractors, but only for the work planned to be
accomplished in the next year or so. It defines the way the
organisations committed to the project will achieve the strategic
objectives defined in the Low
Density schedule is developed
and agreed with the people
actually doing the work and should be realistic and achievable
statement of what will occur in the next 3 months. If this does not
achieve the overall strategic objectives, the problems are resolved in
Density schedule so as to
minimise disruption to current
Current scheduling practice has clearly demonstrated that trying to
predict detailed resource requirements years in advance when no-one
knows who will be doing the work, how effective they will be and
frequently what the details of the work actually are is pointless
only use for this type of schedule is measuring failure after the
event. Unfortunately the requirement for a multi-year,
resource loaded schedule is a far too common contractual and legal
new paradigms proposed in this section of the paper offer a short term
solution based on The
Guide, that can be adopted on
any project using
most of the currently available scheduling tools.
A Resource Optimisation
a resource optimisation approach would involve changing the underlying
philosophical approach embedded in CPM from a belief that the
pre-determined duration and sequencing of activities takes precedence,
constrained by the availability of resources (if resource levelling is
used); to one that recognises the real objective of scheduling is to
keep the resources working effectively (resource work flows) and any
activity sequencing represents a constraint on the locations where
resources can work.
This change in approach would represent a totally new paradigm in the
modern age, although interestingly, the original objective of CPM was
resource optimisation! CPM was dumbed down to its current
form to achieve realistic processing times on the computers available
in the late 1950s; unfortunately almost no-one has moved on from the
basic structure for a CPM model that were fully defined by the early
1960s despite the massive advances in computer power. Re-introducing
resource optimisation would result in:
is a longer term option that could be
as radical as the shift from
barcharts to CPM. Developing
this paradigm will require academic research, resulting in new
approaches to software, contracts and the management of projects.
that activities are variable. Any division of work into activities is
arbitrary and can be changed.
are a consequence of both the quantity and quality of resources
actually assigned to the work. The relationship is complex (not
simplistic resource driven durations) and capable of optimisation based
on the project objectives.
workflows are the core determinant of project outcomes. Optimising
resource workflows minimises cost and time outcomes. Sub-optimal or
disrupted workflows increases cost and time
outcomes (SCL Delay and
tools that are introducing optimisation capabilities include:
ideas outlined in this abstract will be developed in two stages.
initail presentations were Differentiating
between activities and work = Resource Optimization,
presented at ProjectChat 2011,
Sydney, the Construction CPM
conference, Orlando and PMOz,
these presentations was to outline the shortcomings of CPM, review
the alternative methodologies and approaches including Flow-Line,
ToC, Critical Chain, Momentology, Location Based Scheduling,
and RD-CPM, then consider the
additional requirements needed to fully
implement resource optimisation. The first part of the presentation
will outline the concept followed by a discussion period with
colleagues at the conferences.
on feedback from the above, the full paper, Resource
optimisation - a new paradigm for project scheduling
will be developed.