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40 Years and Counting
Steel Backed Timber guardrail
The early concept design for Steel Backed Timber guardrail can be traced
back to 1975. An aesthetic barrier solution was desired by the Great
Smoky Mountains National Park for the Fighting Creek Gap emergency relief-funded
project along TN State Route 73. A steel-backed timber "guide-rail"
was designed and detailed along the top of a reinforced earth retaining wall,
the first design of an aesthetic barrier and wall combination. The design was
detailed by structural engineers at Federal Lands Highway prior to crash test
performance standards.
First in the U.S. Reticulated Root Pile
Structure
In 1977, the Federal Lands Highway installed a Reticulated Root Pile
Structure to stabilize a landslide on the Forest Highway 7 (State Route
162), Mendocino Pass Road, in the Mendocino National Forest, CA.
The installation proved successful in preventing the roadway from
failing during the disastrous storms of 1982-83. Installed at an angle
and in a 3-dimensional circular network, these root piles eventually
lead FHWA to formalize design procedures for micropiles.
Solar heated asphalt storage tank
After eruption of Mt. St. Helens volcano happened in May 1980
Federal Lands Highway evaluated different techniques for volcanic ash
dust abatement and removal. Numerous technology demonstrations projects
occurred during this year, a good one to highlight is the solar
heated asphalt storage tank demonstration that showed how the system
achieved conservation of
electrical power.
Sulfur extended asphalt and Breakaway barricades
Federal Lands Highway provided guidance on using Internally Sealed
Concrete in the Dulles Airport Access Project. The method protects
bridge decks from deterioration by using special wax beads as a part of
the mix in the upper lift. After curing, heating blankets melt the wax
beads to seal the pores in the concrete and protect the deck from
chloride intrusion.
Self Restoring Barrier
Self Restoring Barrier piloted on the George Washington Memorial Parkway
Soil bioengineering
Soil bioengineering utilizing willow cuttings at four sites in the
Cumberland Gap National Park to provide stable and aesthetic creek bank
protection
Coordinated Technology Implementation Program
The Coordinated Technology Implementation Program (CTIP) was
established in 1987 to improve the Federal Lands Highway programs
through mutually funded and developed projects to deploy innovative,
unique, or under-used transportation technology. The initial supported
Federal Land Management Agencies (FLMAs) included the Bureau of Indian
Affairs (BIA), U.S. Forest Service (FS), and the National Park Service
(NPS). The U.S. Fish and Wildlife Service were included in 1999 and the
U.S. Army Corps of Engineers and Bureau of Land Management were added
under Moving Ahead for Progress in the 21st Century Act (MAP-21).
Native Plant Relocation
In 1988, cacti (Saguaro, Barrel, and Ocotillo) unique to the
Sonoran Desert found in the FLH's General Hitchcock Highway project
clearing limits in the Coronado National Forest, Arizona were salvaged,
transported, stored, and then transplanted. A cactus consultant was used
to minimize plant mortality. This method of cactus salvage was then
used on subsequent projects in the roadway corridor.
First U.S. Multi-arch Segmental Bridge
The last segment of the Natchez Trace Parkway's Double Arch Bridge
was put into place on October 6, 1993. The $11 million, 1,572-foot-long
bridge carries the parkway over Route 96 near Franklin, Tennessee.
Engineers had to figure out how to elevate the bridge over Route 96 and
the densely wooded valley below while preserving the natural beauty of
the site. It was the first precast segmental concrete arch bridge to be
built in the United States.
Amended the Endangered Species Act
In 1994, the US Fish & Wildlife amended the
Endangered Species Act of 1973 to list the North American Desert
Tortoise as endangered. However prior to that in 1993, the FLH started
road work on the Lake Shore Drive of the Lake Mead National Recreation
Area, Nevada, which was in the 6.4 million acres of identified Desert
Tortoise critical habitat. The FLH required all workers and visitors to attend on-site tortoise
training, implemented a trash control program to protect the tortoise,
and after surveying the area for tortoise, installed for the first time
temporary Tortoise Fence Barriers to channel the reptiles to culverts
under the roadway. This eventually led the US Fish & Wildlife to
develop specifications in 2005 to standardize fence materials and
construction procedures to confine tortoises or exclude them from
harmful situations, primarily roads and highways.
Internet Connectivity
First Internet connection and installation of an Internet homepage
and FTP server that improved communications with partners, contractors,
consultants and support vendors.
Concrete-steel arch composite bridge
Once again, U.S. is first! The design of the first concrete-steel
arch composite bridge in the U.S began in 1997 for the Hoover Dam
Bypass. The twin-ribbed arch is the widest of its kind in the Western
Hemisphere. At 880 feet, over the Colorado River it is the second
highest bridge in the United States and the highest concrete-arch bridge
anywhere.
Rustic Asphalt Pavement
Rustic pavement is an approach to satisfying our partners' concerns
regarding aesthetics and preservation of historical character. And that
exactly what Federal Lands Highway provided in front of the most iconic
home in the United States. The rustic pavement is based upon a
transparent, amber colored synthetic binder that substitutes for asphalt
in hot asphalt concrete pavement.
Rockery
In 2006, FLH developed for the first time a rational design
methodology and stability evaluation that enabled certification of
rockery design plans by engineers. The first structure built under
these standards was on Guanella Pass in the Arapaho and Roosevelt NF.
Warm Mix Asphalt
Before Every Day Counts, Federal Lands Highway demonstrated in 2007
the use of warm mix asphalt in Yellowstone National Park. The pilot
evaluated two different WMA technologies and established the foundation
for development of our specifications, practices, and uses of WMA on
other projects.
Reservation Road Planner
This game has been effective in increasing the availability of
user-friendly information regarding the transportation planning process.
It has also enabled the tribal community to understand the challenges
associated with highway planning and to become more engaged in
transportation planning projects in their community.
Steel Backed Timber End Terminal
In 2011, the Federal Lands Highway finalized its design and tested
the Steel Backed Timber Guardrail Tangent End Terminal. The first
installation was on the National Park's Rock Creek Parkway.
Aesthetically Pleasing Rockery Stream Restoration
In 2015 the FLH introduced a new innovation to their 2006
first-use-Rockery geotechnical designs, that of stabilizing river
embankment. Adding to their engineered Rockeries, they identified
in-stream hydrodynamic shear stresses for areas horizontally constricted
such as narrow mountain canyons. Deployed for the first time as
embankment protection in the river next to Colorado's County Road 36,
these near-vertical Rockeries replaced conventional 1:1.5 riprap
revetments giving the roadway wider room and saving an estimated
$1,000,000 in rock cuts.
Grouted Riprap Foundation Block
In 2016 the FLH produced engineered design plans for a buried
Rockery bridge foundation support and deployed it on Colorado's County
Road 43 and Lefthand Canyon, and New Mexico's Catwalk projects.
Placed near or below the estimated scour depth these buried foundations
provide sufficient support regardless of bridge abutment type.
Designed as engineered Rockeries (see 2006), these grouted foundations
that meet AASHTO spread footing criteria, are fast and easy to install,
and offer design and construction flexibility and adaptability for
varying field geotechnical and weather conditions. The adjustable
design allows construction to proceed even while the bridge abutment is
under design and the bridge superstructure is being ordered.
Designating Scenic Bikeways: A Framework for Rural Road Owners
With rural agencies experiencing an increase in recreational bicyclists sharing the road with motorists, opportunities exist to pro-actively plan for and provide safe scenic corridors. By following an intentional process, agency goals to enhance visitor experience can be met when bicyclists are attracted to these tourist destinations. As a Federal Lands Highway sponsored toolkit, this Designating Scenic Bikeways: A Framework for Rural Road Owners assists land management agencies, road owners, and proponent groups to communicate and work together in a positive way to develop bikeways. Other topics include rural road safety, bikeway designation, and liability of bikeway designation. Used as a specific example, rural road owners across the country see how to navigate the Oregon Scenic Bikeway Designation Process.
