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NCHRP 20-65 Task 53
Stuart Anderson, Texas A&M Univ.Clifford Schexnayder, Arizona State Univ.
Keith Molenaar, Univ. of Colorado
Independent Cost Estimates for Design and Construction of Rural
& Small Urban Transit Facilities
THESE FACILITIES ARE Usually small Numerous, and Geographically dispersed Diverse types
DIFFICULT TO ESTIMATE BECAUSE:
Variations in facility function & size Features differ Projects often involve renovation Lack of historical cost data Unique risk factors impact cost Estimating processes not structured
PRODUCTS
An Excel spreadsheet Conceptual Estimating Tool
NCHRP Research Results Digest 397: Independent Cost Estimates for Design and Construction of Transit Facilities in Rural and Small Urban Areas (Project 20-65/Task 53).
Available late December
In many cases small urban/rural transit managers only one person trying to handle everything.The estimating tool gives this person the
ability to easily develop agross estimate number
independent of a consultant.
OUR WORK Reviewed the literature Interviewed:
DOT staff, Consultants, and Transit managers
Collected design & construction cost data Identified risk factors Identified risk frequency levels
EARLY IN THE PROJECT LIFE CYCLE
Project definition still uncertain. Use a parametric estimating model.
Association for the Advancement of Cost Engineering International (AACEI) has a parametric model that supports estimation of buildings.
SOURCES of ESTIMATING DATA
RS Means Building Construction Cost Data For feasibility, preliminary, and intermediate cost,use the square-foot cost section of the manual.
RS Means Square Foot Costs for final estimates. However, the square-foot cost data fails to reflect small size and remote location transit facility characteristics.
Judgment is necessary when using square foot data.
Fails to capture the types of facilities
Usable Floor AreaPercent of Area Heated
Exterior Finish
Escalation Factor• Rural Area• US Average• Innercity urban
Percent of Area Cooled
Estimating Tool
TYPICAL PROJECT SIZE
AVERAGE COST FOR FACILITIES
West Coast facilities could be four times more expensive.
RISK MANAGEMENT Soil conditions (contaminated/unexpected). Underground features (debris or utilities). Neighborhood complaints: noise and dust
cause construction delays. Increased scope/ incremental changes in scope. Higher transportation expenses: projects in
remote areas. Lack of competition (i.e., the number of
bidders).
CONTINGENCY
Contingency set according to project type, size, location, and characteristics.
10 to 15 percent of construction cost is an often suggested appropriate contingency.
COST ESTIMATING TOOL For administration, operations, maintenance, and vehicle storage type facilities. Developed in MS Excel with five tabs: Introduction, User’s Guide, Project Information, Estimate Report, and Estimate Details.
The tool supports cost estimating for years 2015 thru 2025.
TOOL BASED ON REGRESSION ANALYSISDesign and construction costs based on similar projects.
Functions for costs were obtained through regression analysis.
The functions used in the tool to predict future costs during the schematic development phase.
Estimate Report from the Tool
LIMITATIONS The tool only supportsconceptual estimating.
The database and tool were constructed based on actual historical cost data available for rural and small urban transit facilities.
CONCLUSIONS1. Target more practitioners involved in rural and
small urban transit facility projects for historical data.
2. Instead of actual data use a Delphi process. 3. Most rural and small urban transit projects are
combinations of administration, operation, maintenance, and vehicle storage. Thus, it may be better to secure data for such facilities.
4. The data for park and ride, shelter bus stops, un-shelter bus stops, and sign-only bus stops is limited.
THANK YOU
A special thanks to Patti Monahan, Executive Director National Rural Transit Assistance Program (National RTAP)For helping us contact Transit agencies across the country.
QUESTIONSStuart Anderson, [email protected]
Clifford Schexnayder, [email protected]