Summer 2009

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In this Issue Connecticut Begins to Use

Connecticut Begins to Use the 1 the Notched Wedge Joint Notched Wedge Joint

Work Zone Safety Training 2 for Law Enforcement Longitudinal joints in asphalt pavements are formed between individual From the T2 Center 2 passes of the paver. Ideally, this longitudinal joint is as durable as the rest of Resource Library the asphalt pavement mat and will have a life span comparable to the rest of the pavement. The most common longitudinal joint failure occurs from a crack forming in the longitudinal joint, this is FHWA Urges Agencies 4 sometimes referred to as the longitudinal joint to Consider “Top Nine” “opening up”. All longitudinal joints will Life-Saving Strategies eventually crack, but the severity and width of the cracking dictates whether or not stan- 2008 HMA Paving Awards 6 dard pavement maintenance activities such as crack sealing can be effective in preventing further pavement degradation. In some cases, Technology Transfer Center 2009 6 the crack in the longitudinal joint will become Fall Calendar so large that it becomes a safety hazard, as bicycle and motorcycle wheels can fit into and become wedged in the crack. Even if the crack does not become 2009 Technology Transfer Expo 7 large enough to present a safety hazard, the crack will allow water to infiltrate into the pavement structure and ultimately damage it. Technology Transfer Center One of the major causes of asphalt pavement cracking, along with longi- tudinal failure, is the thermal cycling that all pavements experience virtually Request Form 8 everyday. These thermal cycles will slightly increase the overall thickness of see Notched Wedge on page 3 ...... Work Zone Safety Training ...... for Law Enforcement ...... This publication is published by the ...... Connecticut Transportation Institute ...... Technology Transfer Center ...... Many local municipal agencies and ...... Phone: (860) 486-5400 private contractors enlist the assis- ...... Fax: (860) 486-2399 tance of local law enforcement to ...... Web: www.t2center.uconn.edu manage in and around their work class to be very ...... zones and to protect the exposed work- helpful and the ...... Supported through a cooperative effort ers. State troopers are also regularly used information to be ...... of the Connecticut Department of by the Department of Transportation in useful for their jobs...... Transportation and the Federal work zones on our highways. This is a We will offer additional sessions of this ...... Administration’s Local Technical huge responsibility for our law enforce- training in the future...... Assistance Program (LTAP) to provide ment officers and it is very important For more information about this ...... information on the latest transportation that they receive proper work zone safety training, visit our website at: ...... www.t2center.uconn.edu or contact ... technology to Connecticut’s state and training. Recognizing proper work zone ...... local government officials. practices will help keep our workers and Mary McCarthy at (860) 486-0377 ...... officers safe. This year in Connecticut, several bills ...... Donna Shea We at the Technology Transfer Center were proposed to our state legislature that ...... PROGRAM DIRECTOR have long been committed to training address improving work zone safety and ...... [email protected] our State and Local highway employees Public Act 09-187 (S.B. 1081) Section ...... on the principles of work zone safety and 47 was passed and encourages the State ...... Mary McCarthy have recently added a training specifically Police, the Post Officer Standards and ...... TRAINING SPECIALIST addressing the role of law enforcement in Training Council, and each municipal ...... [email protected] the work zone. police department to provide work zone ...... We held our first two sessions of safety training for law enforcement in ...... Shelly Desjardin Safe and Effective Use of Connecticut each basic and review police training ...... PROGRAM ASSISTANT Law Enforcement in Work Zones in program...... [email protected] early May and received very positive For more details about the new bill, ...... feedback from our participants. Evalua- please visit: www.cga.ct.gov/2009/BA/ ...... 2009SB-01081-R01-BA.htm ... Vivian Castelli tions show that participants found the ...... PROGRAM AIDE ...... [email protected] ...... From the T2 Center Resource Library ...... State and local transportation and public Preventive Maintenance Project ...... works agencies within Connecticut Selection: Right Road, Right Treatment, ...... may request the following resources Right Time ...... by calling 860-486-5400 or using the Federal Highway Administration and ...... online information request form at Foundation for Pavement Preservation, ...... www.t2center.uconn.edu/ 2000, VHS, 30 minutes ...... resourcerequest.php. Provides state and local maintenance ...... supervisors and highway managers with ...... Protecting Our Pavements: information on selecting the right road ...... PREVENTIVE Maintenance for the right treatment at the right time...... Federal Highway Administration and Addresses various pavement groups, ...... Foundation for Pavement Preservation, environmental effects on pavements, ...... 1998, VHS, 15 minutes and pavement condition measurements, ...... Presents highway agency decision- and presents examples of preventive ...... makers with information about the need maintenance treatments...... for, and benefits of, policies and funding ...... strategies in support of preventive ...... maintenance programs...... 2 www.t2center.uconn.edu ...... Notched Wedge continued the pavement; as the asphalt binder ex- achieving a high degree of compaction at They all work on the same basic principal— pands, it warms and pushes the aggregates the joint. Achieving a high degree of instead of creating two nearly vertical faces apart slightly. Then as it cools, it is unable to compaction provides adequate material so for the longitudinal joint as is done with the pull the aggregates back together as tightly that as the thermal cycling begins to slowly butt joint, during the placement of the first as they were when the material was placed. change the pavement’s dimensions, there paver pass, a taper is created that As there is only so much asphalt pavement is adequate material to minimize the extends eight to twelve inches in a road, in order to increase the thickness, amount that the longitudinal joint from the end of the paver the dimensions in the length and width “opens up”. pass. The CTDOT specifica- must decrease. A prime example of this is The most common method tion requires a small com- the gap that typically forms between the used to make these longitudinal pactor to follow the paver asphalt in a and a garage floor. joints in Connecticut has been and compact the taper. More than likely, the asphalt, at the time the standard butt joint. A longitu- Many contractors have opted of construction, was flush with the garage dinal butt joint typically consists of to attach a plate compactor floor and over time, it has slowly pulled two faces that are essentially vertical that directly to the paver. Compacting back. Another place where this are placed along side of each other from two the taper helps to prevent traffic from phenomenon is quite separate paver passes. As indicated above, tearing the taper apart and it minimizes the evident is in large parking experience has shown that these joints amount of loose aggregate on the roadway. lots where there are may not last nearly as long as the rest The second paver pass then matches up wide cracks. In many of the pavement and may present with the first pass, covering the taper.

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situations, if you were able to somehow safety concerns as well as potential damage Now instead of two vertical faces compris- push the two sides back together, they to the entire pavement structure. ing the longitudinal joint, the interface would fit back together like two pieces of For the 2009 construction season, the between the two paver passes involves a a jigsaw puzzle. In these cases, there is no Connecticut Department of Transportation considerable amount of material; making it material missing from either side of the (CTDOT) is allowing the use of a notched much more difficult for the longitudinal crack, so the overall thickness of the wedge joint to create longitudinal joints in joint to open up. pavement had to increase slightly to form asphalt pavements. There are as many Research conducted by the Connecticut the crack. different names for the notched wedge joint Advanced Pavement Lab at CTI indicates One of the keys to ensuring good as there are different variations of the that the overall average density of longitudi- performance of longitudinal joints is joint construction technique. nal joints constructed using the notched wedge joint is higher than the densi- ties achieved using the butt joint construction. This results in a more durable longitudinal joint. This is not to say that the notched wedge joint is a cure-all that will eliminate longitudinal joint failures, but it should be looked upon as a viable option to achieve the best possible product. In short, to ensure the best possible performance of any longitudinal joint, it is important to make sure that the best construction practices are followed. continued on page 5 Technology Transfer Center 3 FHWA Urges Road Agencies the circulatory roadway. to Consider “Top Nine” are designed Life-Saving Strategies to channel traffic at the entrance The FHWA Safety Program urges State and MEDIAN BARRIERS and provide local roadway officials to consider imple- collision deflection mentation of nine safety countermeasures Median barriers are longitudinal barriers around a center island. Modern round- that show great potential to reduce highway used to separate opposing traffic on a abouts are geometrically designed to reduce fatalities and injuries. As State highway divided highway. They are designed to speeds and deflect collision forces, which agencies develop plans to address the safety redirect vehicles striking either side of the substantially improves safety, while provid- challenges identified in their strategic high- barrier. Median barriers can significantly ing excellent operational performance at way safety plans, they are urged to consider reduce the number of cross-median the intersection. the benefits of investments in these proven crashes and the overall severity of roadway safety tools and techniques. median-related crashes. LEFT- AND RIGHT-TURN AT STOP-CONTROLLED ROAD SAFETY AUDITS SAFETY EDGE INTERSECTIONS

A road safety audit (RSA) is a formal safety The Safety Edge asphalt paving technique Left-turn are auxiliary lanes for storage performance examination of an existing minimizes vertical drop-off safety hazards. or speed change of left-turning vehicles. or future road or intersection. Audit teams A Safety Edge shape is created by fitting Left-turn lanes reduce the likelihood of are independent and multidisciplinary. resurfacing equipment with a device that intersection crashes. They also make turning The team reports on potential road safety extrudes and compacts the shape of the easier for drivers and improve the intersec- issues and identifies opportunities to pavement edge at a specific angle as the tion’s operational efficiency. Right-turn improve safety for all road users. paver passes. This mitigates pave- lanes provide a separation at intersection ment edge drop-offs immediately during approaches between right-turning traffic RUMBLE STRIPS the construction process and over the life and adjacent through-traffic. This reduces AND RUMBLE STRIPES of the pavement. Because the technique conflicts and improves intersection safety. involves only a slight modification of paving Rumble strips are raised or grooved patterns equipment, it has a minimal impact on YELLOW CHANGE INTERVALS on the roadway that provide both an audible project cost. Improved compaction of the warning (rumbling sound) and a physical pavement near the edge is an additional Yellow signal lights that are not timed vibration to alert drivers that they are benefit of the Safety Edge. appropriately are a safety hazard. Yellow leaving the driving lane. They may be change intervals that are not consistent with installed on the roadway shoulder or on the ROUNDABOUTS normal operating speeds create a “dilemma centerline of undivided highways. Rumble zone” in which drivers can neither stop stripes are rumble strips that are placed at A is a circular intersection safely, nor reach the intersection before the the centerline or edgeline. where entering traffic yields to vehicles on signal turns red. MEDIANS AND PEDESTRIAN REFUGE AREAS IN URBAN AND SUBURBAN AREAS

Medians reduce traffic conflicts and increase safety by providing a buffer area between opposing lanes of traffic. Medians can be open (pavement markings only), or channel- ized (raised medians or islands) to separate various road users. Pedestrian Refuge Areas—also known as crossing islands, center islands, refuge islands, pedestrian

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4 www.t2center.uconn.edu Notched Wedge continued The notched wedge joint has additional advantages as well. One of these is that traffic can safely traverse between the freshly- paved lane and the existing pavement. This does still require proper signage to ensure the motoring public is aware that there is uneven pavement. With traffic being able to traverse on and off of the fresh pave- ment, it is not always necessary to pave -to-curb each day. One note of caution with regard to not paving curb-to-curb is that the freshly-placed pavement must extend to the crown of the road to prevent holding water in the event of rain—rainwater retention would create unsafe conditions. Not having to switch the traffic control pattern and islands, or median slow points—are raised back the paving train up increases the islands placed in the to separate efficiency of the paving operation. This crossing pedestrians from vehicles. reduces the overall duration of the paving operation which, in turn, minimizes WALKWAYS disruption to the public. In addition, not having to switch the traffic pattern Appropriately designed walkways increase reduces the exposure of construction safety for all road users. Types of walkways workers. include: The notched wedge joint is not appropriate for lift thicknesses less than • Pedestrian Walkway (Walkway) – 1.5 inches. For applications less than A continuous way designated for 1.5 inches, it is not possible to form the pedestrians and separated from motor notch and the taper as the lift thickness vehicle traffic by a space or barrier. is not sufficient. The notched wedge joint may also not be appropriate for • Shared Use Path – A bikeway or areas with excessive amounts of turning pedestrian walkway physically separa traffic, such as in heavy retail areas. from motor vehicle traffic by an open Large amounts of turning traffic have space or barrier, either within a highway a tendency to severely damage the right-of-way, or within an independent partial joint. right-of-way. Shared use paths may also The notched wedge joint has the be used by pedestrians, skaters, wheel potential to improve the performance chair users, joggers, and other non- of longitudinal joints in asphalt motorized users. Shared use paths also pavements. In order to realize this are referred to as “trails” or “multiple-use improved performance, it is important trails.” to follow best construction practices— if a joint is constructed with poor • – Walkways that are paved workmanship, it does not matter what and separated from the street, generally technique is used to construct it— by curb and gutter. its durability will be compromised.

• Roadway Shoulder – In rural or suburban areas where sidewalks and pathways are not feasible, gravel or paved highway shoulders provide a safer area for pedestrians to walk next to the roadway.

Technology Transfer Center 5 ...... Technology Transfer Center 2009 Fall Calendar

September

2008 HMA Paving Awards 1 Chainsaw Safety & Operations During Storm Clean-Up, Willington 3 Chainsaw Safety & Operations At the 51st Annual Paving Conference hosted on April 8, 2009 by the CAAPA During Storm Clean-Up, Willington (Connecticut Asphalt & Aggregate Producer’s Association), the CCIA 16 Technology Transfer Expo – (Connecticut Construction Industries Association) and the Connecticut University of Connecticut, Storrs Department of Transportation, the following awards were presented: 29 Pavement Preservation Management, Manchester 30 Pavement Preservation Management, Glastonbury To recognize a quality HMA Pavement placed on a municipal roadway, the following team exemplified the highest standards of paving excellence. October

Location: Old Whitfield Street, Town of Guilford 1 Pavement Preservation Techniques: Prime Contractor: American Industries Asphalt & Chip Seals, Monroe Paving Contractor: American Industries 7 Mechanic’s Roundtable Discussion Inspection Agency: Town of Guilford on the Effect of Winter Operations on Municipal Fleets 20-21 Front-end Loader – Train the Trainer 21 Fleet Safety Best Practices, To recognize a quality HMA Pavement placed on a limited access roadway, Burlington the following team exemplified the highest standards of paving excellence. 22 Fleet Safety Best Practices, Storrs 29 Technology Transfer Center Location: Route 9-Newington, New Britain, Farmington Graduation Ceremony, Storrs Prime Contractor: Tilcon Connecticut, Inc. Paving Contractor: Tilcon Connecticut, Inc. Milling Contractor: Costello Industries, Inc. For updates on our training Inspection Agency: ConnDOT – District 1, Maintenance programs, visit us at: www.t2center.uconn.edu

To recognize a quality HMA Pavement placed on an unlimited access roadway, the following team exemplified the highest standards of paving excellence.

Location: Route 190 – Somers Prime Contractor: Galasso Materials, LLC Paving Contractor: Galasso Materials, LLC Milling Contractor: Costello Industries, Inc. Inspection Agency: ConnDOT – District 1, Maintenance

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