- A basic Function : defines a performance feature that must be attained. it reflects the primary reason for an item or system
- In the case of the screwdriver, " transfer torque" would normally, but not necessarily, be the basic function.
- For example, if the desired appliation was to open lids of paint cans, the function would be defined in terms of the transfer of a linear force rather than a rotational force.
- Thus, a clear understanding of the user's need is necessary
- An item may have more than one basic function
A secondary function: aslko defines performance character of a system or item.
- It answers the questrion, " What else does it do ?"
- For example, the basic function of exterior paint is "protect surface. " Then a secondary function is "improve appearance."
Seconday functions support, the basic function.
* Many times, the presence of a secondary function depends on the method chosen to achieve a basic function and, if the method to achieve the basic function is changed, the secondary function may be removed.
Terminologies
- Capital Cost- initial cost of construction, design, land, legal fees, etc.
- Maintenance - the cost of regular maintenance patrol, repair, salaries of maintenance personnel, and maintenance contracts.
- Rehabilitation / Replacement - the cost of replacing materials, equipment or other elements during the life cycle of the entire facility.
- Salvage- income derived from disposal of a facility or the value of unused services life.
- Miscellaneous - other factor to be considered ifr appropriate include:
- FInance cost
- Denial of use
- Lost Revenue
Checklist
- What is the item ?
- Are environmental commitments satisfied ?
- Are other commitments met ?
- How does it work ?
- What does it do or accomplish >
- WHy does it work ?
- What must it do or accomplish ?
- How does it relate to other systems ?
- Why is it needed ?
- Have all of the functions been identified ?
- Have redundant function been identified ?
- Have required functions been identified ?
- Are functional requirements understood ?
SPecification
- Have specifications and requiremnents been reviewed ?
- Are specifications relaistic ?
- Can a modification of the specifications simplify designa and construction ?
- Are the specifications required, or are they just guidelines ?
- Are all performance and environmental requirements necessay and sufficient ?
- Have all of the specifications been interpreted correctly ?
- What are the desireable characterisitcs ?
- Have State and Federal policies, procedures and regulations been reviewed ?
Engineering and Design
- Has the background information been collected
- WHo designed it and when ?
- who determined the requirements ?
- Who must review and approve a change (this would normnally be the Project Manager ) ?
- WHo must approve implementation funcing( the deputy State Highway Engineer Developemtn ) ?
- Who must implement the change (this will probably be the Design Engineer) ?
- Does the design meet or exceed those set forth in the report ?
- What alternatives were considered during design ?
- Why were the lternatives rejected ?
- Are any changes to the design planned ?
- \Doe the drawings reflect state-of the art ?
- What is the design life ?
- What are the Life Cycle Costs ?
Methods and Processes
- Can functions be combined, simplified, or eliminated ?
- Are any non-functional or appearance- only items required ( these should be identified in the Environmental Docuemtns ) ?
-How is construction performance and why ?
Are there any high direct labor costs ?
Are high- cost areas or items identified ?
What is the schedule ( this si very important, because VE cannot be seen as a delaying process) ?
Materials
- Are special, hard-to-get, or costly materials specified ?
- Were alternative materials considered, and if so why were they rejected ?
- Are the specified materials hazardous or difficult to handle ?
- Are there new materials that may perform the same function ?
Maintenance
- Has the Maintenance Division , District Engineer, and the District Maintenance Engineer been consulted ?
- What is normal maintenance ?
Function and Worth
- Are costs assigned to each function ?
- Has a woth been established for each function?
- Have target costs been determine for each functions ?
- Are design requirements established that don't require any function to be performed ?
- Have functional requirements exceeded ?
- Are unnecessary features called for ?
- Can a function be eliminated, entirely or in part ?
- Does it cost more than it's worth ?
- Have all the high and unnecessry cost areas and high cost/ worth ratio areas been identified ?
- Does the potential cost reduction ( net savings) appear to be sufficient to make further VE investigations and potential worthwhile ?
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