To recognize outstanding VE achievements and promote awareness of the importance of this program, the AASHTO Value Engineering Task Force has established national awards to be given to state transportation agencies. These awards are presented every 2 years to agencies that have shown special achievement in either cost-effectiveness or innovation.
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TABLE 10.4 Life Cycle Cost Calculations for Two Pipes A. Annualized cost method
Pipe A has the lower annualized cost. Annual difference = $9873 — 8507 = $1366. Present worth of annual difference = (1/0.0548) X $1366 = $24,900. *Note that salvage values are treated as negative numbers in the summations for annualized cost and present worth. |
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B. Direct present worth method
Pipe A has the lower cost based on present worth. Difference in present worth = $180,166 — 155,311 = $24,900 (same result as in part A). *Note that salvage values are treated as negative numbers in the summations for annualized cost and present worth. |
The VE Task Force presents the awards in the categories of (1) process improvement, (2) project delivery, and (3) preconstruction engineering (design, utilities, right — of-way, and construction). The awards for 2007 for the most value added proposals are summarized below.
Category: Improved Process
Agency: California Department of Transportation (Caltrans)
Project: Antioch and Dumbarton bridges Geotechnical Investigation Requirements to
Develop Retrofit Strategy
Citation:
This unique study analyzed the geotechnical investigation requirements necessary to develop the strategy that leads to retrofit recommendations for the Antioch and Dumbarton bridges. Caltrans will use this study to develop an appropriate retrofit strategy for each bridge. The baseline scope placed heavy emphasis on conducting new explorations and associated laboratory testing to obtain more dependable data (baseline estimate of $12,100,000). The value analysis (VA) team concluded that the objectives of the investigation could be achieved with fewer new exploratory borings drilled to somewhat shallower depths. Other recommended alternatives also improved the project and lowered cost, with implemented savings of $2,350,000 or 19 percent. All recommended alternatives were accepted and implemented.
Category: Project Delivery
Agency: Minnesota Department of Transportation
Project: TH 212 Design-Build Project, State Project No. SP 1017 12
Citation:
The TH 212 Design-Build Project is a $238 million construction project consisting of 11.75 miles of new four-lane divided highway realignment, 7 interchanges, 28 bridges, and numerous retaining and noise walls. The VE proposal is to eliminate a bridge and provide for the realignment of a crossing road to intersect where the main line creek crossing occurs. This combined crossing concentrates impacts and construction activities in one location. This change minimizes environmental impacts to the creek, the big woods remnant vegetation, and the flood plains, and reduces slope stability issues. The VE impacts include savings in project costs, and reduced construction impacts and future maintenance activities. The new design eliminates an insufficient horizontal curve design exception, improves sight distance at an intersection, reduces the total acreage disturbed, and creates less impervious area.
Category: Preconstruction Engineering < $25 Million
Agency: Florida Department of Transportation Project: Protection of US 98 on Okaloosa Island Citation:
US 98 on Okaloosa Island has been damaged by storm surges from at least five tropical events in the last ten years, resulting in more than $16 million in repair work. The purpose of this project was to provide additional protective features to reduce the potential for future damage from similar storm events. The District wanted the additional protection in place prior to the next storm season, which required the project to be designed and constructed in less than one year. The recommendation developed by the team and accepted by management reduced the cost of the $20.6 million project by $8.3 million, or 40 percent, and also reduced the construction time by 50 percent. A key product innovation from the VE team was the recommendation to use Teflon sheet piling to replace conventional concrete sheet piling.
Category: Preconstruction Engineering $25-$75 Million
Agency: Transport Canada, Ontario Ministry of Transportation, and the City of Windsor Project: Let’s Get Windsor Essex Moving, Walker Road and Howard Avenue Grade Separations VE and Risk Study Citation:
Security measures at the U. S. border have caused significant traffic problems in the City of Windsor. One of the problems was the need to x-ray rail cars entering the United States, which reduced train speed and increased traffic delays at major arterial road-rail crossings in the city. An immediate and concerted effort was put into place to grade separate two major urban road crossings. The original project cost estimates increased dramatically due to the rushed design, limited property, business and industrial activities, traffic operations, and a myriad of major utility issues. A VE study and Cost Risk analysis improved communication with the city, Transport Canada, Ontario Ministry of Transportation, and designers; saved $2 million; identified risks; brought certainty to the cost estimates; and clarified project scope.
Category: Preconstruction Engineering >$75 Million
Agency: New Jersey Department of Transportation Project: Route 52 Causeway Replacement Contract A Citation:
The Route 52 Causeway Replacement Contract A project involves the replacement of 1.2 miles of existing Route 52 Causeway, including 2 structures displaying structural, geometric, and safety deficiencies. Bids far exceeded original estimates. The VE repackaging of Contract A converted Rainbow Island from bridge structure to roadway by grade touchdown utilizing fill. Additionally, the VE changes introduced conventional fixed bridges as an alternate design to high-level bascule bridges. VE design and bridge changes reflected through this repackaging effort resulted in a low bid of $141,350,400, with a net savings of $88,636,000, and improved constructibility by acquiring environmental permits that allowed timely construction without seasonal delays.
Category: Preconstruction Engineering >$75 Million—Honorable Mention
Agency: Central Puget Sound Regional Transit Authority (Sound Transit)
Project: 755 Segment of Sound Transit Central Link Light Rail Project Citation:
The 755 Segment of Sound Transit Central Link Light Rail Project extends approximately 5 miles, from the Boeing Access Road to a station at Southcenter Boulevard. This LRT guideway is mostly elevated and parallels or crosses over Washington State Department of Transportation (WSDOT) freeways along much of its route. The design team undertook an intensive value engineering study of the 30 percent preliminary design at the beginning of the final design assignment. The VE study identified significant configuration changes that were forecast to save $23 million and approximately 8 months of construction duration. Sound Transit evaluated and accepted the recommendations for incorporation into the final design. The potential savings and other benefits identified in the value engineering work were validated by the bids received and continue to be realized during construction of the $234 million project.
[1] The alignment should be as directional as possible while still consistent with topography and the preservation of developed properties and community values.
• Maximum allowable curvature should be avoided whenever possible.
• Consistent alignment should be sought.
• Curves should be long enough to avoid the appearance of a kink.
[2] Rounding should be 4 ft where the foreslope begins beyond the clear zone or where guardrail is installed and foreslope is steeper than 6:1. No rounding is required when the foreslope is 6:1 or flatter.
Note: No attempt has been made to include every bridge type in the above tabulation.
[5]From R. L. Brockenbrough and F. S. Merritt (eds.), Structural Steel Designer’s Handbook, 4th ed., McGraw-Hill, New York, 2006. Used with permission.
[6]Z. P. Kirpich, “Time of Concentration in Small Agricultural Watersheds,” Civil Engineering, vol. 10, p. 362, 1940.
[7]The modified Williams equation is found in Maidment, cited below. The original Williams reference is G. B. Williams, “Flood Discharge and the Dimensions of Spillways in India,” The Engineer, vol. 121, pp. 321-322, September 1922.
[8] Entrance and exit. The deceleration and acceleration lanes adjacent to the main roadway can be lighted so that a motorist can safely transition into and out of the rest area. When the main roadway is not lighted, an average illumination of 0.6 fc (6 lx) should be maintained on the deceleration with three to five luminaires along the speed change lanes. On the exit gore and acceleration lane, 0.6 fc (6 lx) is recommended to a point where the motorist can merge onto the main roadway. If the main route is lighted, the entrance and exit lanes should be lighted to a level equal to that of the main route.
• Interior roadways. These are the roads for the entrance gore to the parking areas and from the parking areas to the exit gore. The recommended illumination is 0.6 fc (6 lx) with a uniformity of 3:1 to 4:1.
The design of lighting for rest areas requires consideration of both vehicle and pedestrian needs. Properly designed rest area lighting will enhance the architectural and landscape features of the facility, promote safety by easing the task of policing, and contribute to the rest and relaxation of motorists by adequately lighting the driving, parking, and walking areas. In areas with landscaping or in natural settings, the lighting designer often attempts to make the light poles less noticeable by causing them to blend with the environment. One cost-effective method uses colored fiberglass reinforced poles that blend with the surrounding environment. These poles are usually of the direct burial type that can be installed with or without breakaway devices.
The lighting system designer should be mindful of motorists on the travelway by not allowing glare or spill light from the rest area luminaires to adversely affect their vision. The motorist on the main roadway should be able to see any vehicles leaving the rest area as well as traffic along the main route. The lighting concerns for rest areas can be divided into several distinct areas:
[10] Obtain soil parameters for both backfill and foundation. Usually the cohesionless backfill is slightly larger than Rankine zone. This enables the designer to use the properties of backfill material to estimate earth loads; otherwise the properties of retained material must be used.
[11] Determine the appropriate design cases and load combinations. Load types are designated as follows: D, dead load; E, earth load; SC, surcharge; RI, rail impact; and W, wind load. Typical load combinations are as follows: sloped or leveled fill without rail, D + E; leveled fill without rail, D + E + SC; leveled fill with rail, D + E + RI; and leveled fill with rail and fence, D + E + SC + W.
[12] Determine the overall design height including footing thickness T and stem height H, and select a trial footing width dimension B. (See Fig. 8.20.) Usually the toe
Table 9.2 outlines the major steps required in the development of final construction plans for a noise abatement project on an existing highway. Considerations in several of these steps are as follows.
TABLE 9.2 Project Development Steps for Noise Barriers for Existing Highways
[14] Preliminary engineering
a. Identify project limits
b. Collect data
c. Identify alternatives
[15] Public and municipal involvement
a. Discuss alternatives
b. Decide on system
[16] Preparation of preliminary plans
[17] Preliminary approvals
a. Municipal
b. State DOT
c. FHWA
[18] Final design
[19] Final approval and processing
[20] Contract letting
[21] Materials
a. Concrete Posts. Concrete posts shall be constructed as detailed in the plan and the required specification on pigmented sealer.
b. Wood Noise Walls. The facing lumber and battens shall be any species of southern pine conforming to the applicable provisions of DOT, modified to the extent that the lumber shall contain no holes and have tight knots. No intermixing of lumber species will be permitted within any continuous section of wall. If the wall abuts any earth fill greater than 2 ft (600 mm), the facing planks installed below the top of the fill shall be 8- X 3-in (200- X 75-mm) or 6- X 3-in (150- X 75-mm) lumber with the 3-in (75-mm) dimension being rough-sawn. All facing lumber and battens shall be pressure preservative-treated with an approved waterborne preservative as provided hereinafter. Lumber treated with Millbrite will not be acceptable.
Facing boards shall be surfaced on two sides, and shall be tongue-and-grooved. All plank facing lumber shall be no. 1 structural grade or better. Facing lumber and battens shall be stamped with the appropriate grade mark.
c. Hardware. All hardware for noise wall shall be galvanized and meet the requirements of the American National Standards Institute (ANSI) and ASTM as to strength and testing.
[22]The portions of Art. 10.2 taken from this source are used with the permission of AASHTO.
