Firefighters plea for better roads and bridges
The Missouri State Council of Fire Fighters are pleading with state officials to focus on the safety of state’s transportation system. The organization, which represents over 6,000 professional firefighters across the state, has released an open letter to the state.
“There are 20,000 miles of bridges and highway crossings in Missouri without shoulders,” Eric Latimer, 4th District vice president of the Missouri State Council of Fire Fighters, writes. “Missouri ranks third in the nation in structurally deficient bridges, and 65 percent of our roads and bridges are rated in “fair” or “poor” condition.”
The organization has studied the benefit of good roads and bridges. It is a proven fact that less people die when good transportation conditions are maintained.
“Between 2005 and 2012, as bridge and highway conditions improved, roadway fatalities decreased by more than 34 percent,” Latimer says.
“If we do not find a long-term funding solution, our roads will deteriorate, putting the safety of the public and our first responders is at risk,” Latimer writes.
A road without fibers is a road soon to be in need of repair
New research is reaffirming the benefits of steel or synthetic engineered fibers in asphalt pavements and concrete, where they enhance performance, replace fine matter, and in the case of concrete, control shrinkage cracking and keep deicing salts away from reinforcing steel.
For decades, fibers of all origins have been hawked as cure-alls for pavement problems. Engineered materials have competed with reclaimed waste products like carpet scraps for their place in pavements, and when a performance problem developed, fibers in general – not the use of questionable materials – took the blame.
But now, fibers as an engineered material have taken their place in the toolbox of products with utility in road construction.
Synthetic fibers for asphalt
Cold climates, but also heat and rain in warmer climates cause cracks and deterioration in asphalt, says Scott Nazar, technical manager, FORTA Corp., a supplier of synthetic fibers. “DOTs and owners of other paved surfaces (e.g. airport runways and parking lots) can enjoy longer pavement life and increased structural stability if the asphalt mix is reinforced with synthetic fibers,” he says.
For instance, asphalt at 3.5 inches of depth, reinforced with synthetic fibers, is as strong as asphalt at 5.5 inches of depth not reinforced with fibers, Nazar says. “These owners can save in the short term and in the long term,” he adds, “because roads reinforced with synthetic fibers last longer and crack less in the first place, no matter whether the environment is hot or cold.”
However, the majority of asphalt pavement work is of the mill-and-fill variety, he says. In these situations, the synthetic fibers can be used to extend the life of the thin overlay, because decreasing thickness is usually not an option.
“Not all fibers are created equal, and the difference matters for our roads,” Nazar adds. “Before contractors make the decision to use fiber technology to reinforce roads, they need to know the differences between types of available fibers that could dramatically impact the life cycle of a project.”
Engineered fibers for asphalt may include asphalt stabilization additive fibers, asphalt reinforcement fibers and fiberglass reinforcement. “Historically, discussions about using fibers for asphalt mixes have centered on cellulose fibers to prevent drain down that occurs when using stone matrix asphalt mixes (SMA) or other high asphalt-content mixes,” Nazar says. “The use of cellulose allows designers to put more asphalt cement in the mix without having a soupy mess.”
Another such mix is the polymer-modified, open-graded friction course (OGFC), which minimizes fines that could inhibit movement of surface water through the lift. Today’s OGFCs utilize cellulose fibers to forestall drain-down of liquid asphalt, although warm mix asphalt used for OGFCs can eliminate cellulose fibers in those mixes.
One of the first technologies using fibers was stress-absorbing membrane interlayer (SAMI). “Constructing SAMIs involves applying emulsion and spraying on a layer of fiberglass fibers, then adding on another coat of emulsion and aggregate chips,” Nazar says. “The SAMI provides a two-dimensional mat for preventing cracks from migrating through the pavement structure.” However, he adds, while the SAMI layer itself may not crack, cracking can occur in layers above and below the SAMI.
Until now, most fibers were derived from plastic and often melted in the mixing process. A portion of the melted fiber did help to modify the asphalt, increasing rut resistance and also cold weather cracking resistance, he says.
We’re in a different age of blended fiber use today.“We’re in a different age of blended fiber use today,” Nazar told Better Roads. “High tensile strength fibers can be added to the asphalt mix during production at the plant, providing crack resistance throughout the entire depth of the pavement layer in which it is placed. High tensile strength fibers include aramid fibers able to withstand temperatures from -320 deg F to 800 deg F.”
A blend of fibers works well for the road agency, he says. “I’ve found a blend of aramid and polyolefin fibers is the way to go,” Nazar says. “It’s best of both worlds; the blend reduces both high temperature rutting potential and thermal cracking. I have even noticed improved densities of fiber mixes because the fibers keep the material from spreading out under the rollers during breakdown compaction. These high tensile fibers have also shown to provide the best benefit when tested at high-strain values equal to or greater than 250 micro strains.”
Fibers enhance thin overlays
Thin asphalt overlays are a sustainable, low-cost alternative to conventional hot mix asphalt overlays, but their performance can be enhanced with the optimal design, including additives like fibers, say Songsu Son, Ph.D. candidate, and Imad L. Al-Qadi, professor of engineering, and director, Illinois Center for Transportation, University of Illinois at Urbana-Champaign, in their 2014 Transportation Research Board paper, “Engineering Cost-Benefit Analysis of Thin Durable Asphalt Overlays.”
“Significant improvement of pavement performances has been achieved with regard to material selection and modification, mix design, and construction technology,” they say. “However, most of these improvements require high-quality aggregate and expensive modified asphalt binder or special equipment for construction.”
New-design asphalt mixes have come to the fore.In response, new-design asphalt mixes have come to the fore as stakeholders seek better-performing mixes at lower cost, say Son and Al-Qadi. These new asphalt mixes offer significant cost savings while improving structure and function characteristics, including durability, friction, quietness, rutting, cracking and moisture susceptibility resistance.
To evaluate field performance of these new mixes under actual traffic loading and environmental conditions, including the control mixes, pavement sections with six asphalt mixtures and various wearing surface thicknesses were constructed.
Two typical Illinois surface mixtures were selected as control mixes: a 9.5-mm NMAS coarse dense-graded mixture (F-mix) and a 12.5-mm SMA. The SMA mixture generally requires more durable aggregates, modified asphalt binder, and cellulose fibers, which makes it more expensive than typical dense-graded mixtures.
Three fine dense-graded asphalt mixes with a 9.5-mm NMAS and one SMA with a 4.75-mm NMAS were developed for a relatively thinner wearing course. Locally available aggregates were employed, among them being a steel slag/fiber mix designed to provide good friction and high resistance to stripping and permanent deformation due to the use of steel slag.
A blend of polypropylene and aramid fibers was added into the slag mix to improve its tensile strength, allowing placement at a relatively thinner layer thickness. A PG 70-22, SBS-modified asphalt cement was utilized, and the aggregate mix was 62.2 percent dolomite, 17.5 percent natural sand, and 20.3 percent slag.
Field testing was performed immediately after construction and every four months up to two years.In-place field testing was performed immediately after construction and every four months up to two years. Testing at these intervals provided results for initial field performance and short-term performance for each section. The in-place field testing included onboard sound intensity measurement, laser longitudinal texture profiling, locked-wheel friction, and walking foot inclinometer (dipstick) rut measurement.
Then the pavements were evaluated and scored, and using a formula, the authors converted the ranks to numbers to calculate the overall performance numerically from 0 to 10 (worst to best). The steel slag/fiber mix scored second highest in their performance rankings.
“In general, the control mixes resulted in lower performance scores compared to the new mixtures,” Son and Al-Qadi. “The 4.75-mm SMA section with a 1-in wearing surface provided the highest overall performance score.”
Stay tuned to BetterRoads.com for the rest of this three part series! –>
Our 2015 Contractor of the Year contest is open for entries
Our 2014 Contractor of the Year, Jeremy Hiltz, accepts his award in Las Vegas.
Equipment World’s Contractor of the Year program—which honors the forward thinkers, high achievers and just plain good people in construction—is now open for entries.
Each year, the editors of Equipment World select 12 finalists for this prestigious program, now in its 15th year. Each finalist and their guest receive a free weekend at the Wynn resort in Las Vegas, capped by VIP attendance to the 2015 NASCAR Sprint Cup race on March 8th. For a taste of what this event involves, check out the video below, which includes a personal invite from Mike Rowe.
In addition, each finalist is featured in the pages of Equipment World magazine, with the 2015 Contractor of the Year winner appearing on our May cover. This year’s winner, Jeremy Hiltz of Jeremy Hiltz Excavating, Ashland, New Hampshire, calls being named Contractor of the Year “the pinnacle of my career.”
To be a candidate, you must:
- Have between $3 million and $15 million in annual revenues (this can be your current revenues, or an average for the past 3 years).
- Have at least 10 years of construction company ownership experience.
- Have a proven, excellent safety record
- Represent the construction industry in a positive way.
Interested? The first 50 contractors to completely fill out an application will receive a Cat hat, courtesy of Caterpillar, sponsor of the Contractor of the Year program for more than 14 years.
This article was written by Marcia Gruver Doyle, Editorial Director of Equipment World.
H.R. Green’s Larry Stevens elected as 2014-2015 APWA president
The nearly 29,000 American Public Works Association (APWA) members elected Larry Stevens, P.E., PWLF, as its 2014-2015 president during the 2014 APWA International Public Works Congress and Exposition held in August in Toronto.
Stevens, project director for Johnston, Iowa,-based HR Green Inc. will lead the organization as well as APWA’s 17-member board of directors.
Vehicles covered in oil and grime after construction project gone wrong
Drivers headed west on Highway 19 near Northfield, Minnesota, found an unpleasant surprise on their vehicles. Commuters saw signs warning of road construction, but didn’t think anything of it until they exited their vehicles after reaching their destination. That’s when they found their vehicles covered in oil and grime.
It was the result of a simple sealcoating project gone horribly wrong. A surprise rain storm prevented the resurfacing substance from bonding with the gravel and caused it to instead bond to vehicles.
Minnesota Department of Transportation Public Affairs Coordinator Mike Dougherty explained that the oil mixture used for sealcoating is supposed to bond with the gravel and road surface as it dries, but if water is added, the oil isn’t able to dry. Since it rained, the mixture didn’t dry but splashed onto vehicles instead.
“[The storm] was an unanticipated issue,” Dougherty said. “The rain was the component that made this go incorrectly.”
Dozens of drivers were reportedly affected before State Patrol was able to reroute traffic from the area.
MnDOT is holding contractor, Astech Corp. out of St. Joseph, Minnesota, responsible for the damage. MnDOT has said it received hundreds of calls from angry drivers who are having a difficult time cleaning the resurfacing mixture off their vehicles. Many drivers who were affected have been forced to reach out to local auto centers that claim to have a solution to restore vehicles back to their original state.
Highway and Bridge contract awards down 14 percent
The value of highway and bridge contract awards was down 14 percent in the first seven months of 2014 when compared to the same period in 2013.
According to American Road and Transportation Builders Association (ARTBA), state and local governments awarded $29.8 billion in highway and bridge work between January and June 2014. When adjusted for material costs and inflation, $34.6 billion was awarded during the same time period in 2013.
The pullback in spending is likely due to the lack of a long-term Highway Trust Fund solution.
According to ARTBA’s analysis of McGraw Hill data, 25 states awarded fewer highway and bridge contracts by June 2014 than they did a year ago while awards were actually up in 21 states and Washington, D.C. In five state awards were flat, neither up nor down more than five percent.
Watch construction of Gerald Desmond Bridge 24/7
The Port of Long Beach is offering you real-time footage of the construction related to replacing the Gerald Desmond Bridge. Three webcams have been installed on the World Trade Center rooftop facing west toward the bridge, at Pier A facing south and at Pier T facing north, which means you can watch the construction 24/7.
The footage will broadcast at newgdbridge.com and through the project’s mobile smartphone app. Search for “LB Bridge” in the App Store, Google Play or Windows Phone Store to download the app.
People watching from the website will be able to zoom in and out, and select full-screen views for a great look of the action.
“There is a tremendous amount of public interest in the construction of this new bridge,” John Pope, Port of Long Beach Community Relations Manager, said in a statement. “However, there is not a safe, accessible vantage point within the Port to view construction activities. These new webcams offer the best, safest way for everyone to experience the historic construction of what will be an iconic bridge for our city.”
The Gerald Desmond Bridge was built in 1968 and helps to ferry nearly 15 percent of the nation’s waterborne cargo. Unfortunately it has slowly deteriorated over the years. Things have gotten so bad that nets had to be attached to the bridge to catch falling debris.
Think you're a good driver? Try staying in these crooked lanes [VIDEO]
Virginia Department of Transportation crews had a mess to clean up when temporary striping tape installed on Interstate 66 peeled off and created crooked, narrow lanes. The crooked lanes caused mass confusion among drivers which resulted in lengthy traffic delays.
Two vehicles were involved in a nasty accident, however, it has yet to be determined if the accident was caused by the crooked lanes. Both vehicles were towed away.
The markings were installed on Aug. 15 as part of a temporary lane shift expected to last several months. Crews rushed to fix the markings. VDOT is still investigating what caused the markings to peel off.
“We created quite a nightmare for commuters and we apologize for that,” said VDOT spokesperson Joan Morris.
VDOT assures drivers that once it finds out what caused the marking to peel off, it will make sure it never happens again.
Vermeer names third-generation family member Jason Andringa incoming president, CEO
Vermeer Corporation has named Jason Andringa incoming president and CEO, taking over the position from his mother, Mary Vermeer Andringa, and continuing the Vermeer family’s leadership of the company into the third generation.
The transition will be fully effective on Nov. 1, 2015. On Nov. 1 this year, Jason will assume the role of president and chief operating officer, a position he will hold for one year before assuming full leadership responsibilities.
Since 1989, Mary Andringa has headed the firm along with her brother Bob Vermeer, who currently serves as the company’s chairman of the board. On Nov. 1, she will assume the role of CEO and chair of the board, while Bob will become chair emeritus. “As an entire family, we are proud to announce the third-generation leadership who we know with confidence can propel us to new heights,” Mary says.
Vermeer was founded in 1948 by Mary and Bob’s father, Gary Vermeer, a member of the Association of Equipment Manufacturer’s Hall of Fame. The company, now known in construction for its trenchers, directional drills and environmental equipment, began when Gary created a mechanical hoist for his grain wagon. He retired as CEO in 1989 and passed away in 2009.
Jason currently serves as president of the firm’s Forage and Environmental Solutions division. Prior to this position he served as vice president for dealer distribution and global accounts, and spend three years in the Netherlands as managing director for Europe, Middle East, Africa and CIS. He joined Vermeer in 2005 after serving as a staff engineer at NASA’s Jet Propulsion Laboratory.
“I am honored to have the opportunity to lead Vermeer as a family-owned and operated, global company into a prosperous future,” Jason says.
This story was written by Marcia Gruver Doyle, Editorial Director of Equipment World.
Roads and bridges in Pennsylvania fail to make the grade
According to the American Society of Civil Engineers (ASCE), the state has the worst transportation infrastructure in America. ASCE gave the state a D-minues grade, the worst of any other state, citing 44 percent of the roads in Pennsylvania are in poor condition.
Without more money, motorists in the state will continue to waste an average of 182 hours and 86 gallons of fuel in traffic jams. The report estimates the cost to drivers in lost time and wasted fuel amounts to $3.7 billion per year.
Bridges in Pennsylvania need work as well, earning a grade of D-plus. 23 percent of the state’s bridges are deficient which is the worst in the country.
“Deficient road conditions are a factor in the majority of fatal traffic accidents, and safety was a primary reason that AAA strongly supported additional transportation funding investment,” AAA East Central Director of Legislative Affairs Theresa Podguski said. “We anticipate a better report card next year.”
A lot of states are finding a need for more transportation funding. Alabama’s roads and bridges also need a lot of work.
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