A Study of Lean Construction Practices in Gaza Strip

4.5 Remove or Reduce the Influence of Waste as it is Observed
Simulation has been used in each activity to measure the duration and number of steps.
Productivity data in Table (3.1) was used in the simulation model. Results are shown on
Table (4.17). The full simulation results are shown in appendix (C).
The results that were reached from mobilization and plain concrete are explained as
follows ( the other activities use the same methodology).
Figure (4.2) shows how lean is applied to mobilization and excavation activity. Firstly
by using the five why tool. The steps were reduced from seven (Table 4.3) to three steps
(Table 4.18). The seven steps are cleaning the site, demolishing existing walls, building
engineer's office, excavation work, checking soil, extended excavation and checking the
new extension excavation land.
The first three steps can be reduced to one step by coordinating cleaning, demolition
and building. These three contractors can begin work at the same time. The sixth and
seventh steps can be avoided because there is a design error.
Create 1
0
Cleaning Ex cav ation Laboratory
0 0 0
Dispose 1
0
0
Figure 4.2 Arena simulation of mobilization and excavation
Secondly, applying productivity to three processes. Cleaning lasted for 48 hours,
demolition took 32 hours and building engineer's office took 32 hours. These three
processes may start at the same time. Since the project was ready, the duration of
cleaning is supposed to be 48 hours (Table 4.3). This is considered non-value added
process.
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