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LEAN CONSTRUCTION Lean construction main objective
is to maximizes value and reduces waste.
It applies specific techniques in an innovative project delivery approach.
It including:1. supply chain management, 2. Just-In-Time techniques.
LEAN CONSTRUCTION
Just-In-Time(JIT)
Supply ChainManagement
(SCM)
LeanConstruction
maximizes valuereduceswaste
Based on LeanManufacturing, of the Toyota
Production system
High productivity
LAST PLANNERSYSTEM
LEAN CONSTRUCTION
As well as the open sharing of information between all the parties involved in the production process.
Lean manufacturing is an outgrowth of the Toyota Production system.
Developed by Taichii Ohno in Toyota in the 1950s.
LEAN CONSTRUCTION
Ohno identified several wastes in mass production systems in car industry such as:
1. overproducing2. waiting time 3. transporting
LEAN CONSTRUCTION
also, in other areas such as:1. processing methods; 2. unnecessary stock on hand; 3. unnecessary motion;4. defective goods; 5. failure to meet customers’ needs;6. high waste through out the process.
LEAN CONSTRUCTIONWomack and Jones (1996) suggested that
there are five key principles that need to be monitored when lean construction systems are applied in construction. Those are:
Value-clarifying the customer’s needs; the supply chain involvement in all stages,
from inception to completion; By clarifying activities or products that signify value.
LEAN CONSTRUCTION
Value stream: By mapping thewhole value streamestablishing cooperation between
all parties involved;identifying and eliminating waste; From taking such steps the
construction process can be improved.
LEAN CONSTRUCTION
Just-In-Time(JIT)
Supply ChainManagement
(SCM)
Business FlowPull
Perfection
LeanConstruction
maximizes valuereduceswaste
Based on LeanManufacturing, of the Toyota
Production system
JIT onlyconsiders the
Resourcesrequired
Construction LeanImprovement Programme
(CLIP),(Supply chain)
High quality product with minimallead-time
Eliminating delays and disruptions
WORK PLAN
Construction Planning is a fundamental and challenging activity in the management and execution of construction projects
It involves:1. Managerial 2. Technological3. Social factors.
WORK PLAN
A good construction plan is the basis for developing the budget and the schedule for work.
Developing the construction plan is a critical task in the management of construction.
In developing a construction plan, it is common to adopt a primary emphasis on either cost control or on schedule control.
WORK PLAN
ConstructionPlan
Resourcesand cost
ResourceOrientated
Criticalpath
NetworkAnalysis
TimeOriented
Scheduleof
workbased plan
IndirectCost
involved
DirectCost
involved
Budgetbasedplan
WORK PLAN
A database program called WorkPlan has been developed to systematically provide weekly work plans.
WorkPlan adopts the Last Planner methodology, which implements a number of lean construction techniques.
WORK PLAN
A week before the actual work starts WorkPlan guides the management team step by step through the process of producing work packages in order to identify issues such:
checking constraint resolving constraints Sending out work packages allocating resources
WORK PLAN
Then at the end of the week, collecting site progress data such as:
reasons for cost overrunreason for time overrunreason for delaysDisruptionsetc
WORK PLAN
This well planned and systematic approach helps the management team to create quality work plans.
They learn from any failurea good WorkPlan is a weekly work planbased lean constructionproduction scheduling
WORK PLAN
screening work package Constraint percentage of planned completed (PPC) Scheduling of construction work is often
done with the help of computer tools It implement the critical-path method
(CPM)
WORK PLAN
based on activities of given duration and unit resources allocated to them
as well as predecessor relationships between activities
for different parties involved in a construction project to communicate with one another whom should be doing what work and when.
WORK PLAN
The application of lean production techniques in construction has been triggered by its success in manufacturing (Womack and Jones 1996).
Weekly work plans can be developed as valuable tools for production planning and control.
WORK PLAN
This is possible through the application of lean construction techniques.
In the application weekly work plans are generated using a database (Choo, Tommelein, Ballard, and Zabelle -1998).
Value Engineering-Constructability
VALUE ENGINEERING Value Engineering (VE) has been defined as: the systematic effort directed at analyzing the
functional requirements of: systems equipment facilities procedures and supplies for the purpose of achieving the
essential function at the lowest total (life-cycle) cost.
Value Engineering-Constructability
Also, all the efforts are focused on meeting needed issues such as:
Performance; Reliability; quality, maintainability; aesthetics, Safety; fire resistance; while, at the same time, achieving lowest life-cycle
cost.
Value Engineering-Constructability
Constructability implementation can act as a predecessor to value engineering.
Providing information through constructor input and lessons learned from past projects such that value engineering may be more effective.
Value Engineering
Implementation of value engineering involves several steps:
1. Information;2. functional analysis;3. creative mind;4. Evaluation;5. planning & proposal; 6. Implementation;7. follow-up.
Value Engineering
The creative step involves a brainstorming session where life-cycle cost alternatives, for design components are considered.
Value engineering may be performed in two ways:
(1) Proactively (2) Reactively
Value Engineering(Value Analysis)
What Is Value Engineering? Value Engineering (V.E.), also known as Value Analysis, is a systematic and function-based approach to
improving the value of products, projects, or processes. VE involves a group of people following a structured
process. The process helps team members communicate better
across boundaries. understand different perspectives, innovate, and analyze.
Value Engineering
What does Value Engineering do? Value Engineering improves value. On a major road development, improvements
to value might include: reducing the life cycle cost of an interchange,
enhancing safety in a design; or reducing impacts to the public by
shortening the duration of a construction project.
Value Engineering
Value Engineering uses a combination of creative and analytical techniques to identify alternative ways to achieve objectives.
The use of Function Analysis differentiates Value Engineering from other problem solving approaches.
VE focuses on delivering the product or service at the best price.
This is achieved by incorporating those value characteristics deemed most important by the customer.
Value Engineering
How does V.E. work? V.E. follows a structured thought process
to evaluate options. Every V.E. session goes through a
number of steps: Gather information -What is being done
now? Measure Performance -How will the
alternatives be measured?
Value Engineering Analyse Functions -What must be done?
What does it Cost? Generate Ideas (Brainstorming) -What else
will do the job? Evaluate and Rank Ideas -Which Ideas are
the best? Develop and Expand Ideas -What are the
impacts? What is the cost? What is the performance?
Present Ideas Sell Alternatives
This is not helpdesk figure (different source)
CostingTeam (4)
DesignTeam(3)
Value Team(2)
Client Team(1)
Initial VE meetingAll parties involved
(A)
VE ReviewWorkshop
ResultSummarised
Recommendation put forward
VE IdeasImplemented
The overall VE study process
(A) general introductoryProgrammingBudgetDelegation of ResponsibilityFinancial Issues
(2) Qualitative Analysis(3)Quantitative and Qualitative(4) Quantitative Analysis
Value EngineeringVE
TO ANALYZEFUNCTION
REQUIREMENTOF
facilitiesequipmentsystemsprocedures
Performance;Reliability;
quality, maintainability;aesthetics,
Safety;fire resistance;
while, at the same time,achieving lowestlife-cycle cost.
TO MEET NEEDED ISSUES
Highproductivity
Reducing the lifecycle cost
Enhancingsafety in a
design
(2)Reactively
(1)Proactively
There are four important steps most be taken inmodified VE job plan. They are as follow:
Value Engineering
VETO ANALYZEFUNCTION
REQUIREMENTOF
Highproductivity
(2)Reactively
(1)Proactively
1
• 1. Information PhaseBriefing by the Client -Feasibility study with client presence-Outline proposals-Scheme design
2• 2-VE Steps- Validation or preparation of cost estimate- Familiarisation and
breakdown of data into elements- cost models- Functional evaluation of areas to isolate high cost, poor value areas,
3• 3-Speculative Phase- Team review of project-idea listing- Development of
final idea listing
4
• 4-Analytical Phase-Evaluation of ideas listing-Selection of high cost areas for in-depth study,- Team brainstorming for generation of possible alternatives suitable for in-depth analysis- Investigate alternatives- Team review of analysis-Preparation of proposal drafts.
INTEGRATING LEAN SUPPLY WITH WORK PLAN & VE
Just-In-Time(JIT)
Supply ChainManagement
(SCM)
LeanConstruction
maximizes valuereduceswaste
Based on LeanManufacturing, of the Toyota
Production system
High productivity
LAST PLANNERSYSTEM
ConstructionPlan
Resourcesand cost
ResourceOrientated
Criticalpath
NetworkAnalysis
TimeOriented
Scheduleof
workbased plan
IndirectCost
involved
DirectCost
involved
Budgetbasedplan
VETO ANALYZEFUNCTION
REQUIREMENTOF
facilitiesequipmentsystemsprocedures
Performance;Reliability;
quality, maintainability;aesthetics,
Safety;fire resistance;
while, at the same time,achieving lowestlife-cycle cost.
TO MEET NEEDED ISSUES
Highproductivity
Reducing the lifecycle cost
Enhancingsafety in a
design
(2)Reactively
(1)Proactively
