NCHRP 20-65 Task 53 Stuart Anderson, Texas A&M Univ. Clifford Schexnayder, Arizona State Univ. Keith...

Post on 18-Jan-2016

212 views 0 download

Tags:

Transcript of NCHRP 20-65 Task 53 Stuart Anderson, Texas A&M Univ. Clifford Schexnayder, Arizona State Univ. Keith...

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, s-anderson5@tamu.edu

Clifford Schexnayder, cliff.s@asu.edu