Other Scheduling Methods - Construction Project Scheduling and Control - page 314

Figure 11.17 Combination of solutions 2 and 4 for avoiding an intersection in the LSM
Figure 11.18 Rate of successor slower than rate of predecessor in the LSM
activity B during intervals, we can reduce the crew size to slow the rate until there is
a safe time buffer (a combination of solutions 2 and 4; see Figure 11.17).
The time buffer is necessary only if the rate of the successor is faster than the rate
of the predecessor. If the rate of the successor is slower than the rate of the predecessor,
the time buffer can start at zero. Naturally, the successor (activity B) will finish after
the predecessor (activity A). See Figure 11.18.
To calculate the time buffer (Figure 11.19), we start from the end: allow activities
A and B to finish simultaneously. Then,
DurationA = DurationB + Time buffer