Major Dennis Edwards Tunnel construction wraps, additional work to continue ...
Overnight closures at the Dennis Edwards Tunnel along U.S. Highway 26 east of Seaside are complete and the $6.5 million improvement project is set to finish by the end of June, according to the Oregon Department of Transportation. However, additional work to stabilize the area surrounding the tunnel is expected to continue through mid-August.
ODOT hopes to wrap major construction before Fourth of July weekend, and flagging may continue now through July 1 as a result, according to ODOT Public Information Representative Kimberly Dinwiddie. The tunnel will remain open all of the holiday weekend.
Work just outside the east entrance of the tunnel to stabilize the hillside running adjacent to Highway 26 will continue through the summer.
"There is a moving landside on the north slope of Highway 26," Dinwiddie said. "The slide has been active this past winter and into the spring and motorists driving by have likely seen a little bit of debris coming off the hillside."
In the coming weeks, ODOT will hire a contractor to remove hillside material in a controlled manner. When the hillside work is scheduled, motorists will encounter the same driving restrictions that applied to the tunnel work, including brief periodic lane closures. Flagging around the clock Monday through Thursday is planned, and may include delays of up to 10 minutes, she added, but lanes will not be closed on weekends, Friday afternoons, or during major events.
"We need to do this work for safety reasons," Dinwiddie said. "We would rather have the material removed by the experts rather than having it come down by itself. If it came down by itself that could mean the road would be closed for several days."
The work will remove debris, but won't stabilize the hillside.
"To stabilize the hillside would require a major engineering project," Dinwiddie said. "There are hundreds of landslide areas across the state. It is the nature of our geology."
The danger posed to motorists, bicyclists and pedestrians is minimal, according to Dinwiddie, and ODOT expects to be able to retain the hillside through preventive work and monitoring.
Motorists will also find traffic delays east of the Edwards Tunnel at the Quartz Creek Bridge on Highway 26 where road crews are replacing all the bridge joints in addition to original repair work.
The tunnel project to reline the Dennis Edwards Tunnel's timbered ceiling began in January. The tunnel life was only designed to last 70 to 80 years. ODOT engineers said the timber lining reached the end of its service life and needed to be replaced.
Concrete Reinforcing Fibers - News
"The shotcrete is a specifically designed concrete that is mixed with reinforcing steel fibers and we sprayed that material onto the tunnel liner and to the reinforcing cage," he said. The timber headers that shape the arches of the tunnel were removed
No fingerprints, no DNA, no hair, no clothes fibers. He remembered how West looked that day, bruised and traumatized. But the medical records seemed at odds with the sexual assault she described: They showed no internal tears or bleeding.
A wooden mold is applied to the beam and concrete is then injected through holes to fill up the areas previously chipped or fallen out. After the concrete dries, sheets of a carbon-fiber mesh material are applied to the concrete to add tensile strength
The plans are meant to be used with glass fiber reinforced concrete, but they could be adapted for other casting techniques. The designs take into account important safety considerations such as venting. "A student told me about a fire pit he designed
The tubes do not rust like iron or chip like concrete bridges, he said. The bridges are corrosion-resistant, he said, and do not require steel reinforcement. The bridge in Fitchburg is the seventh constructed with the carbon fiber tubes.
Reinforced concrete
This is portland cement concrete containing higher-strength, solid materials to improve its structural properties. Generally, steel wires or bars are used for such reinforcement, but for some purposes glass fibers or chopped wires have provided desired results.
Unreinforced concrete cracks under relatively small loads or temperature changes because of low tensile strength. The cracks are unsightly and can cause structural failures. To prevent cracking or to control the size of crack openings, reinforcement is incorporated in the concrete. Reinforcement can also be used to help resist compressive forces or to improve dynamic properties.
Steel usually is used in concrete. It is elastic, yet has considerable reserve strength beyond its elastic limit. Under a specific axial load, it changes in length only about one tenth as much as concrete. In compression, steel is more than ten times stronger than concrete, and in tension, more than 100 times stronger.
As reinforcement for concrete, steel may be used in the form of bars or rods, wire, fibers, pipe, or structural shapes such as wide-flange beams.
Bars are the most commonly used form . The size of a bar usually is specified by a number that is about eight times the nominal diameter; sizes range from No. 2, a nominal 0.6 cm bar, to No.18, a nominal 5.7 cm bar.
During construction, the bars are placed in a form and then concrete from a mixer is cast to embed them. After the concrete has hardened, deformation is resisted and stresses are transferred from concrete to reinforcement by friction and adhesion along the surface of the reinforcement. The bonding may be improved mechanically by giving reinforcing bars raised surfaces; such bars are known as deformed bars. They are generally manufactured to standard specifications, such as those of the American Society for Testing and Materials (ASTM).
Similarly, deformed wires used as reinforcement provide greater bond than smooth wires. Deformed wires are designated by D followed by a number equal to 100 times the nominal area in square inches.
Individual wires or bars resist stretching and tensile stress in the concrete only in the direction in which such reinforcement extends. Tensile stresses and deformations, however, may occur simultaneously in other directions. Therefore, reinforcement must usually be placed in more than one direction. For this purpose, reinforcement sometimes is assembled as a rectangular grid, with clips or welded joints at the intersections of the wires or bars. For example, prefabricated wire grids, called welded-wire fabric, often are used for slab reinforcement in highway pavement and in buildings.
Concrete Reinforcing Fibers - Bookshelf
Dams and Reservoirs, Societies and Environment in the 21st Century, Proceedings of the International Symposium on Dams in the Societies of the 21st Century, 22nd International Congress on Large Dams (ICOLD), Barcelona, Spain, 18 June 2006
Short term deflection of plain and fiber reinforced concrete. ... Not all fibers are specifically manufactured as a concrete reinforcement; and those which ...Fiber reinforced concrete, developments and innovations
Concrete and masonry databook
5.6.1 Fiber Reinforcement for Concrete Fibers made from metal or synthetic materials may be added to concrete to improve its performance. ...Fundamentals of high-performance concrete
B FIBER-REINFORCED PLASTIC COMPOSITES 9.7 HISTORICAL DEVELOPMENT Use of ... GFRP reinforcement is more durable and efficient as concrete reinforcement. ...The contractor's guide to quality concrete construction
Other Types of Reinforced Concrete Two other types of reinforced concrete are available for special applications: fiber-reinforced concrete and ferrocement. ...Day-by-day Info Directory
Concrete Fibers, Inc. provides concrete reinforcing fibers ...
Concrete fibers provide secondary reinforcement in concrete and prevent drying shrinkage cracking.
Synthetic Industries, Inc.
Manufacturers of Fibermesh concrete reinforcement system.
Nycon, Inc.
Provides nylon fibers for reinforcement.
PVA reinforcing fibers
5lb bag PVA reinforcing fibers ... Like steel, these PVA fibers have high tensile strength and a greater modulus of elasticity than regular concrete. ...
Reinforcing Concrete by Adding Fibers - The Concrete Network
Using fibers to reinforce concrete instead of using welded wire mesh.