The trick is in the timing

But a research team from the Adelaide Business School have introduced a novel twist to the current planning methods available, that may just help keep projects on track. They have developed a new method for determining buffer sizing in Critical Chain Project Management (CCPM).

Buffers are key to the CCPM method. ‘Traditional project planning offers a task schedule that is longer, allowing for delays. But people quickly fall into the “student syndrome” trap. In other words, if I have two days to do this task, why would it do it in five hours?’ says Dr Zarghami, University of Adelaide PhD graduate and research lead. In CCPM, the time allocated to an individual task is pared down, with the excess reallocated to buffers at critical points of the project.

These buffers focus on resources, often the cause of project delays. In a first, the research team have developed a way of calculating these buffers more accurately – by treating resources as variable, rather than just available or unavailable.

Their calculations are based on probability. Even equipment, such as trucks, can and do fail, causing delays and problems. As Dr Zarghami acknowledges, ‘Maybe there’s only a 2% chance that the motor will fail, but there is still that element of probability that it could fail and not be available.’ So, by treating resources as variables, rather than fixed binary points, more realistic buffers can be created, and project managers can work towards reasonable timeframes and expectations.

This method also helps with agility, allowing the project to re-adapt to dynamic environments where schedule and resource allocation require flexibilityAssociate Professor Graciela Corral De Zubielqui

It’s difficult to tell just want impact this method can have on major projects. ‘I can’t say it’s a panacea. Determining buffer sizes is only one part of the overall project plan.’ Says Dr Zarghami. ‘However,’ as Assoc Prof Corral de Zubeilqui notes, ‘project management methodologies have not been revisited or reconsidered in a long time, and this does have the potential to help organisations to operate in a more dynamic environment in which resources are tighter and harder to find. This method also helps with agility, allowing the project to re-adapt to dynamic environments where schedule and resource allocation require flexibility,’ added Assoc Prof Graciela Corral de Zubielqui.

Project delays are obviously very costly, but they can also affect company reputations and have political and economic consequences. Any new tool that can give project managers more control, and more knowledge about which resources have the greatest impact on overall completion, is surely a good thing. By using this new statistical method, project managers may be better able to identify and respond to problems quickly.

The CCPM is still a relatively new method for managing projects and the industry is crying out for more research in this area. The School of Business research team are already working on other closely related projects that may impact project outcomes. ‘We are looking at extending this research to address the accelerating complexity of projects. In particular, rooted in network theory, forthcoming research aims to develop a complexity index that assists in providing a more accurate estimate of buffer sizing,’ says Assoc Prof Corral de Zubielqui. Like many things, often the trick is in the timing. 

Seyed Ashkan Zarghami, Indra Gunawan, Graciela Corral de Zubielqui and Bassam Baroudi, 2019, Incorporation of resource reliability into critical chain project management buffer sizing, International Journal of Production Research.