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Dealing With The Unexpected - What To Do When Things Don't Go As Planned
15th In A Series From The IPBA
Pipe bursting is a reliable and proven method of replacement of deteriorated or under capacity utility lines. The IPBA has developed a recurring series of technical articles and this article will be written with the understanding that the reader has an advanced knowledge of the pipe bursting process.
As with any underground construction there are times when things do not go as planned and pipe bursting is no exception to that rule. Managing changes that are either anticipated or unexpected can often mean the difference between a project being considered successful in the eyes of the owner or public, and profitable for the contractor performing the work.
As a contractor that has field experience with pipe bursting of both water and sewer as well as static and pneumatic processes of pipes from two – 24-inches, I have seen firsthand what real time decision making can do towards the success and the profit and loss of a project. In a pre-job risk assessment it is important to identify what could possibly go wrong and what are the field crews going to do about it. These situations can typically be put into two categories: items within our control and items outside of our control. An experienced project team should be able to adjust in real time to surprises or problems that arise in the field, thus greatly increasing the chances of a successful project.
Items within our control would include employee skills, layout of the project plan, selection of process (static or pneumatic), size and type of bursting machine, execution of the project work plan, equipment reliability and the sequence of the work.
Out of control
Items often considered out of the contractors control include geotechnical conditions, pipe repairs made of unknown materials, narrow trench geometry, etc. A contractor is often able to influence these situations even if they cannot be completely managed or anticipated. For example, pre-existing pipe repairs in a sewer line, although not always clearly indicated prior to the start of work (a water main replacement with mechanical repairs comes to mind) can be reasonably anticipated to exist. Something like this is often referred to as “known unknowns.” By having a project team with the tools and ability to recognize and adapt to such problems dramatically reduces the potential for failure.
Let's review a list of some of the potential situations that could occur on a pipe bursting project and some of the potential remedies.