Fast tracking – Trying to do things in parallel, which were originally scheduled sequentially. When the design is 80% complete, we can start construction.
Crashing – The process of trying to compress the duration of activity by deploying more resources into it. Reducing the duration of the compound wall construction by deploying more resources into it.
Fast tracking and crashing is done either to optimize the schedule or when there is a delay in the schedule. Both crashing and fast tracking must happen on the critical path, else one may not get the desired results.