A Study of Lean Construction Practices in Gaza Strip

More documents

Recommendations

Info

2. Unnecessary material handling. 3. Tradesmen slow/ineffective. 4. Far distance between place of working and storage. 5. Poor distribution of materials in site. 6. Lack of proper maintained pathways. 7. Difficulty in motion of worker in the site 2.8.7 Over-processing Over-processing is unintentionally doing more processing work than the customer requires in terms of product quality or features – such as polishing or applying finishing on some areas of a product that won’t be seen by the customer. Doing more work tends to keep people “busy,” but adds no “value” such as writing a comprehensive legal agreement when a simple agreement would suffice, replacing more parts than necessary, spending extra time doing more analysis than is really necessary, unnecessary complexity. Over-processing waste of construction in the Gaza Strip is due to: 1. Conversion waste from cutting uneconomical shapes. 2. Using excessive quantities of materials more than the required. 3. Wrong handling of materials. 4. Insufficient instructions about handling. 5. Lack of workers or tradesmen or subcontractors’ skill. 6. Difficulty in performance and professional work. 7. Interaction between various specialists. 8. Using untrained labors 28
2.9 Summary The lean construction takes its idea from the lean manufacturing by making customer’s needs as the main priority of the company objectives. The application of lean construction started in 1992 by International Group of Lean Construction. The main objective of lean construction is to increase the value added activities and remove or reduce the non-value added activities in the project. The impact of lean construction gives more value to the client with less waste of time and resources. It helps contractors improve processes and overall project delivery, improve productivity by improving the planning. The impact is also an approach well suited to accommodate change, reduces cost, accelerates delivery, improves both quality and safety, delivers products or services on time and within budget. It also injects reliability, accountability, certainty, and honesty into the project environment and reduces system noise, improves project delivery methods and promotes continuous improvement in project delivery methods through lessons learned. Lean thinking consist of five points: Value, value stream, flow, pull and perfection. Koskela (1992) applied lean production in the construction with eleven criteria which are: non-value-added activities reduction, increase output value, variability reduction, cycle times reduction, simplifies by minimizing the number of steps, increase output flexibility, increase process transparency, benchmark, build continuous improvement into the process, balance flow improvement with conversion improvement and focus control on the complete process. The lean construction tools are: Just in time (JIT), last planner system, increased visualization, first run studies, productivity, the 5S process, fail-safe for quality, the 5 why's and daily huddle meetings. The seven wastes according to the research thesis of the construction wastes in the Gaza Strip (Said, 2006) are: over-production (ordering of materials that do not fulfill project requirements defined on design documents, and waiting for replacement, over ordering or under ordering due to a mistake in quantity surveys, over ordering or under ordering due to lack of coordination between warehouse and construction crews), defects (damage materials on site, unnecessary inventories in site which lead to waste, poor quality of materials, use of incorrect material, thus requiring replacement, equipment frequently breakdown, poor technology of equipment, shortage of tools and equipments required, rework due to workers’ mistakes, damage to work done caused by subsequent trades, poor workmanship and choice of wrong construction method ), 29
Page 1: The Islamic University of Gaza Dean
Page 4 and 5: Acknowledgment I would like to expr
Page 6 and 7: ABSTRACT This research deals with t
Page 8 and 9: 2.5.6 Increase Output Flexibility .
Page 10 and 11: Appendices Appendix (A): Daily Repo
Page 12 and 13: List of Tables Table 2.1: Conceptua
Page 14 and 15: List of Figures Figure 2.1: Reducti
Page 16 and 17: 1.1 Statement of the Problem Most o
Page 18 and 19: 2.1 Lean Construction History Chapt
Page 20 and 21: 2.3 Impact of Lean Construction Acc
Page 22 and 23: Table 2.1 Conceptualization of lean
Page 24 and 25: for measuring the percent plan comp
Page 26 and 27: 2.5.6 Increase output flexibility F
Page 28 and 29: � The more wastes inherent in the
Page 30 and 31: 3. System requires the need to deve
Page 32 and 33: the work flow, material flow, produ
Page 34 and 35: • Straighten Next, materials were
Page 36 and 37: Material Productivity = Total Outpu
Page 38 and 39: investigation showed that 25 percen
Page 40 and 41: 7. Poor technology of equipment. 8.
Page 44 and 45: inventory (Wrong storage of materia
Page 46 and 47: Main Activity Mobilization and exca
Page 48 and 49: 4. Sort the candidates in order of
Page 50 and 51: 4.2 Project Activities Lean constru
Page 52 and 53: Table 4.2 represents the resources,
Page 54 and 55: Main Activity Slab work Building wo
Page 56 and 57: 4.4.1 Mobilization and excavation T
Page 58 and 59: 4.4.4 Neck column Table (4.6) shows
Page 60 and 61: 4.4.7 Ground beam The twelve proces
Page 62 and 63: 4.4.10 Ground floor slab The eleven
Page 64 and 65: No. 9 10 11 Table 4.14 Non-value ad
Page 66 and 67: 4.5 Remove or Reduce the Influence
Page 68 and 69: The result by using arena simulatio
Page 70 and 71: Table 4.17 Simulation results No. A
Page 72 and 73: Table 4.17 Simulation results (Cont
Page 74 and 75: 4.5.3 Foundation Table (4.20) shows
Page 76 and 77: 4.5.7 Ground beam Table (4.24) show
Page 78 and 79: 4.5.11 Column first floor Table (4.
Page 80 and 81: 4.6 Identify the Cause of Waste Tab
Page 82 and 83: Percent of value adding time 35% 30
Page 84 and 85: Table 4.33 Total project duration N
Page 86 and 87: Then, the processes with the greate
Page 88 and 89: number of workers to 12 workers sho
Page 90 and 91: Activity Process Ground floor Colum
Page 92 and 93:
Actual project duration was 6000 ho
Page 94 and 95:
Date Process Assigned Process Compl
Page 96 and 97:
5.1 Conclusion Chapter Five Conclus
Page 98 and 99:
References 1. Abudallah Fawaz , (20
Page 100 and 101:
27. Graham, P. and Smithers, G., (1
Page 102 and 103:
51. Serpell, A.; Venturi, A. and Co
Page 104 and 105:
Appendices (A) Daily report Date Ac
Page 106 and 107:
04/09/2003 06/09/2003 07/09/2003 08
Page 108 and 109:
18/12/2003 20/12/2003 21/12/2003 22
Page 110 and 111:
11/04/2004 12/04/2004 13/04/2004 14
Page 112 and 113:
Appendix (B) Arena Simulation Compu
Page 114:
Appendix (C ) Simulation result of
show all

A Study of Lean Construction Practices in Gaza Strip

Create successful ePaper yourself

Delete template?

Save as template?