A Conversation with Jeffrey Milton with VDOT

Jeffrey Milton with VDOT

Author: Lorella Angelini, Angelini Consulting Services, LLC

Jeffrey Milton, Bridge Preservation Specialist with Virginia DOT (VDOT), is a bridge preservation leader in his State and at national level.

Jeffrey is member of the AASHTO Subcommittee on Maintenance chairing the Technical Working Group on Bridges. He is also part of the FHWA Bridge Preservation Expert Task Group and actively involved with TRB and NCHRP, where is covers a number of Committee Memberships.

  • TRB Standing Committee on Structures Maintenance – AHD30 Member
  • TRB Standing Committee on Bridge Preservation – AHD37  Member
  • NCHRP Project Panel on Development of Guidelines for Uniform Service Life Design for Bridges D12108  Chair
  • NCHRP Project Panel on Condition Assessment of Bridge Post-Tensioning and Stay Cable Systems Using NDE Methods D1428  Member
  • NCHRP Project Panel for Extending the Life of Highway Bridge Coating Systems Through the Use of Spot Painting with Minimal Surface Preparation D1430  Member

Jeffrey is a member of the FHWA Technical Panel for update of NHI Bridge Maintenance Training Course and development of NHI web-based Bridge Preservation Training Course. He is also member of the TSP2 oversite panel.

I recently had the opportunity to speak with Jeffrey about VDOT bridge preservation program.

How does bridge preservation fare at VDOT?

Using Virginia structure data as of September 1, 2017, the total number of structures in Virginia inventory sums up to 21,124, of which 13,113 bridges and 8,010 culverts. Out of these structures, 19,469 entail VDOT owned/maintained structures, of which 11,910 bridges and 7,559 culverts. The number of city, county and town owned/maintained structures is 1,463, including 1,044 bridges and 419 Culverts

VDOT defines Condition Categories for structures as Good, Fair and Poor.

  • Good Condition means a low General Condition Rating of 6 or greater
  • Fair Condition: a low General Condition Rating equal to 5
  • Poor Condition: a low General Condition Rating of 4 or less

Condition Categories for the 19,469 VDOT Owned/Maintained structures currently report a limited number of structures in Poor Condition.

  • 13,891 (71.3%) of the structures are in Good condition
  • 4,818 (24.7%) of the structure are in Fair condition
  • 760 (3.9%) of the structures are in Poor condition

What does bridge preservation entail at your DOT?

At VDOT bridge preservation is part of a comprehensive Bridge Program that includes preventive and restorative maintenance, painting, rehabilitation and replacement.

Examples of preventive maintenance are bridge cleaning, deck sealing, sealing joints, thin deck overlays and spot and zone painting.

Restorative maintenance includes deck patching, rigid deck overlays, reconstructing/closing joints, superstructure repairs, substructure repairs, fatigue retrofitting, scour repairs, cathodic protection and electrochemical chloride extraction.

Painting encompasses spot and zone painting, over-coating, complete removal and repainting.

Superstructure replacements, deck replacements and culvert rehabilitation are examples of rehabilitation. Rehabilitation and replacement are not part of VDOT Bridge Preservation Program, which focuses exclusively on preventative maintenance, restorative maintenance and painting.

What criterion does VDOT use to determine actions that should be implemented?

Our criterion can be outlined in three points.

  • Preventive maintenance candidates are structures in Good Condition (a low General Condition Rating of 6 or greater)
  • Restorative maintenance candidates are structures in Fair Condition (a low General Condition Rating equal to 5)
  • Rehabilitation and replacement candidates are structures in Poor Condition (a low General Condition Rating of 4 or less).

We also use element level condition states and defects to develop specific maintenance and preservation treatment options.  We previously used AASHTO Pontis for our bridge Management system, and we are now investigating the use of AASHTO BrM.

As a general guideline, we want to make sure that preventive, painting, and restorative works are performed before the onset of serious deterioration while the structures are still in good or fair conditions.

We adopted a breakdown for the allocation of bridge structure funds that foresees 15% for preventive maintenance, 10% for painting, 25% for restorative maintenance and 50% for rehabilitation / small structure replacement. This balanced breakdown helps select efficient and effective actions, as it is essential in order to maintain a healthy bridge structure inventory.

Can you outline key bridge preservation strategies at VDOT?

Some VDOT structure/bridge preservation strategies include:

  • Eliminate deck expansion joints. The designer must evaluate the feasibility of joint elimination. When elimination is not possible, the designer will have to submit justification, including supporting calculations, to the Assistant State Structure and Bridge Engineer for Maintenance.
  • Reconstruct concrete adjacent to joints and install strip seals. When joints cannot be practically eliminated, specific activities should be performed such as perform concrete substructure surface repair and apply waterproofing coating/treatment to pier and abutment seats and ends of beams/girders.
  • Install asphalt plug joints with back-up sealers on decks having asphalt overlays.
  • Prepare concrete decks using hydro demolition and place rigid concrete overlays.
  • Coat beam ends and substructure caps under joints.

What challenges have VDOT encountered in the implementation of bridge preservation strategies?

Like many Agencies, our corporate culture has previously taken a worst first approach to the bridge program, with major emphasis on structurally deficient structures.  We have made great progress with our management in promoting a preservation approach focusing on preventive, painting, and restorative works for extending the service life of our inventory.

Can you inform of new technologies that have been recently adopted by VDOT?

We have started using hydro demolition and placement of rigid concrete overlays to protect the concrete deck. We are also investigating the use of hydro-demolition and hydro-milling for concrete removal on substructures.

VDOT Structure and Bridge Division and the Virginia Transportation Research Council are investigating the use of remotely operated data gathering devices and remotely operated maintenance devices. These devices, which include Microsoft HoloLens, unmanned aerial vehicles (drones) and crawling devices designed for bridges and culverts, can be outfitted with various sensing technologies, such as infrared, high resolution cameras and impact (sound).

We are in the process of conducting a research project in order to investigate the use robotic devices in conjunction with lasers for the removal of paint from steel beams and girders.

How can TSP2 help VDOT reach its goals?

TSP2 provides a very valuable platform for sharing information of treatment methods, best practices and research projects among the States, especially when participating in regional and national working groups.  The TSP2 staff provides support to the preservation program in Virginia and throughout the nation.

 

LINKAGE

Chapter 32 of the VDOT Manual of the Structure and Bridge Division (File 32.01-9-12) shows the VDOT Bridge Planned Preventive Maintenance Program.  A link to this document follows: http://www.virginiadot.org/business/resources/bridge/Manuals/Part2/Chapter32.pdf

VDOT is in the process of reviewing and updating this document (Ed Note).

A link to the FHWA Bridge Preservation Guide follows: https://www.fhwa.dot.gov/bridge/preservation/guide/guide.pdf

This guide will be updated by the FHWA Bridge Preservation Expert Task Group (Ed Note).

Posted in Interview

Emphasis on Case Studies at the MWBPP Meeting in Early November

Author: Lorella Angelini, Angelini Consulting Services, LLC

Bridge preservation case studies will be featured at the 2017 Midwest Bridge Preservation Partnership (MWBPP) meeting held at the Marriott City Center in Minneapolis, MN on November 6-8. The meeting will also focus on actions for deck and joint preservation and emergency response procedures for exceptional events, such as flooding, bridge hits and fire.

Bridge preservation practitioners attending the meeting represent the States that are part of the Midwest TSP2 Partnership region: Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, Oklahoma, South Dakota and Wisconsin. At the meeting preservation practitioners from DOTs and other owners will be interacting with contractors, consultants, academia and manufacturers that have a stake in bridge preservation in the Midwest region. Manufacturers will also have an opportunity for showcasing their products and technologies.

As with all TSP2 Bridge Preservation Partnership meetings, time will be dedicated to round tables where owners, consultants, academia, manufacturers and contractors can exchange information related to their experience with bridge preservation, underscoring challenges and solutions for extending the service life of concrete and steel bridges.

MWBPP mission is to provide a platform for bridge preservation practitioners to exchange, promote and advance best practices, new technologies and innovation in the areas of highway bridge management, inspections, preservation and maintenance.

For information please contact Darlene Lane at 517-432-8220 and email hidden; JavaScript is required

LINKAGE

2017 MWBPP Annual Meeting

Posted in General, General News, News

A Conversation with David Miller, Chief Maintenance Engineer with Louisiana DOTD

David Miller with LaDOTD

Author: Lorella Angelini, Angelini Consulting Services, LLC

About one year ago, David Miller was promoted to the Chief Maintenance Engineer position at the Louisiana DOTD (LaDOTD). Before that he served for several years as the Bridge Maintenance Engineer for the State. David is happy his new position gives him the opportunity to remain involved with the bridge program and he can take preservation issues further. 

As Chief Maintenance Engineer David Millers’ responsibilities include managing the ferry systems, signs and signals, bridge inspection, loss prevention and truck permits.  He is also in charge of the statewide bridge crews that work on complex preservation projects and the statewide crews that specialize in putting up signals and sign trusses. On the other hand, the crews that carry out the day-to-day work for the maintenance of bridge and road assets are managed by the nine LaDOTD Districts

Some of the longest bridges in the United States are located in Louisiana. With 175,000,000 square foot of deck area (2016 FHWA data), Louisiana ranks as the fourth largest state for bridge deck area. It follows Texas, California and Florida, which all have a higher number of bridges than Louisiana. In addition to having long bridges that span over the Mississippi and across marshlands, Louisiana has also a large number of timber bridges (third most in the US), which were built years ago during the expansion of local timber industry.

What does bridge preservation entail at LaDOTD?

Bridge preservation can be divided in two parts in Louisiana. One part entails larger preservation projects that are managed through the bridge preservation program that has been in place for about 10 years. It is part of the overall bridge replacement, bridge rehabilitation capital program and allocates from $30 to $40 M per year specifically for bridge preservation projects. Projects are selected through a committee that takes input from the districts and are back checked with deterioration models from Pontis in the past, AASHTO BrIM currently.  This part is where the heavy lifting on the preservation side comes in.

The other part is funded through the operating side of the budget. This entails maintenance and preservation activities that are done by districts’ bridge crews and statewide crews. Unfortunately, our crews tend to do more emergency-related work than preventative maintenance because many bridges in Louisiana are in poor condition. (In 2016, LaDOTD reported 1,739 structural deficient bridges, corresponding to 13.5% of 12,915 total number bridges. Ed. Note). Our crews also focus on preserving our timber bridges to keep them open and safe.

What is your bridge preservation strategy?

Our strategy at LaDOTD is to improve the condition of bridges and their ratings every time it is possible. For example, if a paint project is scheduled for a particular bridge, we do not necessarily want to do the painting only. We evaluate whether there is a structural rehabilitation project that can be done in parallel to painting to improve the overall rating of the bridge. A pure painting project does not move the rating of a bridge from poor to good.

The majority of our preservation activities have been focused on bridges that are in poor conditions. Our goal is to bring these bridges from poor to fair or from poor to good. Mainly because of lack of funds, we are not at the point that we can do activities on bridges that are in good condition, which is the recommended preservation approach.

Our gas tax, 16 cents per gallon, was implemented in the 80s and has not changed, or been indexed, since then.  We recently went through an effort with our Legislators to try to increase the tax in order to have more funds to maintain bridge and road assets. Unfortunately, this effort failed to pass. This will make our responsibilities in maintenance difficult to carry out as we continue to deal with our relatively large number of posted and structurally deficient bridges. It will take additional funds to be able to get ahead of the curve and do more of strategic preservation activities on our bridges.

Four of the top five longest bridges in the United States are in Louisiana. Most of these bridges belong to the interstate system and are in good shape. However, having to deal with long bridges puts an additional strain on our resources.  Preserving a bridge that is 20-miles long and has a twin structure requires a lot of money. A tremendous amount of money is required just to tackle one element of the bridge, for instance the deck.

What is the LaDOTD strategy with structurally deficient bridges?

We have prioritized work on structurally deficient and posted bridges that are on the major truck routes.

We are also planning to replace all our timber bridges.  This poses a challenge as we have the third most timber bridges in the country.  Most of these bridges, which were built in the 50’s and 60’s, are deteriorated beyond their service life.

What are the challenges in the implementation of your preservation strategy?

As I said before, the biggest challenge for us is funding. Our administration understands the need for additional funding for highway infrastructure, so hopefully there will be additional funding in the future.

Do you have a success story you would like to share?

Probably the biggest success story is just the fact that LaDOTD has a bridge preservation program that has been in place for 10 years. There have been some major projects completed through this program. One of these was the rehabilitation of Huey P. Long – O.K. Allen Bridge crossing the Mississippi in Baton Rouge. This is a steel truss bridge over a mile long. It is a both a railroad and highway bridge, the only bridge of this kind owned by the state.  It was brought to fair condition through a rehab project that entailed structural repairs with member strengthening and painting. It was a typical preservation-style project even though it was necessary to use more than the normal preservation funds.

Is TSP2 helping LaDOTD reach your goals? And how?

TSP2 provides a very valuable forum for networking with peers from other states and federal agencies. During the annual South-East Bridge Preservation Partnership (SEBPP) meeting, we get the opportunity share knowledge, success stories and failures. We can learn from states that are ahead in certain areas of bridge preservation. We can also learn their preservation strategies and how they were successful in getting funding increases for their department. TSP2 is definitively a big plus for us.

I would suggest improving the liaison between TSP2 and the Sub-Committee on Maintenance (SCOM), specifically in relation to the flow of research projects. We streamlined this process at SCOM about two years ago (David is Vice Chair on the SCOM Bridge TWG for Asset Management, Performance Measures and Environment. Ed. Note) and now it is TSP2 that is addressing this process. There is the need for fine-tuning research needs between SCOM and TSP2.  There is definitively room for improvement in this aspect of the collaboration.

TSP2 is now sending representatives from its four regions to SCOM. This really helps with creating continuity between SCOM and TSP2.  For example, at SCOM we recently learned from the North-West TSP2 Region about the benefits of bridge washing and how to get through the process with environmental groups.  That would have never happened had the North-West Bridge Preservation Partnership (NWBPP) not sent representatives to SCOM.

In general, the more time SCOM and TSP2 people meet and have discussions the better they will be able to get on the same page.  Flow of information between SCOM and TSP2 is improving, but it could get better.

 

LINKAGE

Bridge Preventive Maintenance Program:

http://wwwsp.dotd.la.gov/Inside_LaDOTD/Divisions/Engineering/Bridge_Design/Pages/Preventive_Maintenance.aspx

Posted in Interview

Deck Preservation and Retaining Systems are Key Topics at the Upcoming NEBPP in NJ

Author: Lorella Angelini, Angelini Consulting Services, LLC

In less than two months, on September 11-13, the Northeast Bridge Preservation Partnership (NEBPP) meeting is scheduled to take place in New Brunswick, NJ. The meeting encompasses four sessions: deck preservation, research needs, case studies and retaining systems.

Over 150 bridge preservation practitioners specialized in maintenance and repair of concrete and bridge structures will be gathering in New Brunswick from the States that comprise the North-East region: Connecticut, District of Columbia, Delaware, Massachusetts, Maryland, Maine, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont. In addition to representatives from the owners, the meeting will also bring together contractors, consulting engineers, academia and manufacturers, who can showcase their innovation in products and services.

As with all TSP2 Bridge Preservation Partnership meetings, time will be dedicated to round tables where participants have the opportunity to exchange information and discuss practices that extends the service life of bridges.

Through the free and open exchange of ideas and information, the NEBPP’s mission is to better serve those who use the northeast transportation system. NEBPP strives to use innovation, new ideas, new products, and the combined experience of participant States to make bridge maintenance procedures and repairs the best that can be provided.

For more information please contact Darlene Lane at 517-432-8220 and email hidden; JavaScript is required

LINKAGE

https://tsp2bridge.pavementpreservation.org/northeast-nebpp/annual-meetings/2017-2/

Posted in General

A Conversation with Graham Bettis, Director of Field Operations with TxDOT

Graham at the SEBPP meeting in WV

Graham at the SEBPP meeting in WV

Author: Lorella Angelini, Angelini Consulting Services, LLC

I met Graham Bettis at the recent TSP2 SEBPP meeting in Charleston, WV, where he spoke about bridge preservation experiences at the Texas Department of Transportation (TxDOT) in the events of extreme flooding.

Graham has developed a vast and diverse bridge preservation experience at TxDOT. With 53,875 bridges in its 2016 inventory, this state has the largest number of bridges in the USA. The Texas bridge inventory consists of 35,489 “on-system” bridges, which are located on the state highway system and maintained by TxDOT; and 18,386 “off-system” bridges, which are not part of the state highway system and are under the jurisdiction of the local governments (cities, counties, and municipalities).

Graham is the Director of Field Operations for the Bridge Division at TxDOT. His responsibilities include the bridge inspection program and the management of the geotechnical group, in addition to bridge construction and maintenance. Graham is a member of the TSP2 SEBPP Committee.

What does bridge preservation entail at TxDOT?

Since 2001 a primary focus at TxDOT has been addressing Structurally Deficient (SD) bridges, an effort that was fully supported by our Administration. We have been very successful with this. The number of on-system SD bridges in Texas decreased from 483 in 2006 to 187 in 2016, while the number of off-system SD bridges in Texas decreased from 1,642 in 2006 to 678 in 2016. Now that the number of SD bridges is low, we have a unique opportunity to focus on developing and implementing an overall bridge asset management program.  

It is worth noting that an SD bridge is one with maintenance concerns or one that frequently floods. SD bridges do not pose a safety risk; however, to remain open to vehicular traffic, they are often posted with reduced weight limits that restrict the gross weight of vehicles using the bridges. SD bridges are inspected frequently and are closed to the traveling public if determined to be unsafe.

Could you talk about the bridge asset management program at TxDOT?

In the last two years we established the Bridge Maintenance and Improvement Program (BMIP), which is entirely focused on bridges that are in “fair” condition.

The number of bridges in “good” condition in Texas is increasing, while the number of bridges in “poor” conditions is decreasing, which is what we want. However, the number of “fair” bridges is increasing because we have a number of “good” bridges that are becoming “fair.” So we really want to concentrate on hitting those “fair” bridges that have a condition rating of 5 or 6 and push them back up to “good” so as to maintain their service life in an economically efficient manner.

How has the BMIP evolved over the past years?

The program is still in its infancy. It began three years ago and we have just one engineer to oversee it. In the first couple of years we were focusing on 10-12 bridges per year, mainly large projects. Now we are addressing 70-80 bridges per year, which is in line with BMIP target.

Could you highlight the key elements of the bridge preservation strategy at TxDOT?

As I said before, a key element is to identify those structures where it makes financial sense to address defects early on and get ratings back up to good (condition ratings of 7 or higher – ed. note).

We are also working on a bridge life-cycle cost analysis, in which we compare the cost of repair/rehab versus replacement. While some rehab measures are very cost effective, others are extremely expensive.  We want to have a method that allows us to identify those bridges that can give us another 5 or 10 years of service life before replacing them versus investing in rehabilitation.

If it costs $1M to rehabilitate a bridge today, compared to $1.5 M to replace it 10 years from today, we will likely choose the replacement because the level of quality we get out of new bridge construction is very high. Even if it costs more initially, replacement is an economical solution in the long run because we will get 100 years of service life out of a new bridge.

The goal of the rehabilitation program at TxDOT is to extend the service life of bridges by 25 years, which is one-fourth of the service life extension we get with replacement. In other words, even successful repairs have fairly limited effective life in comparison with new construction.

We are trying to improve all aspects of rehabilitation, from engineering evaluation to plan preparation and actual quality of the work itself. None of these aspects are quite as effective as for new construction. There are a lot of opportunities for improvement in repair and rehabilitation.

What are the challenges in the implementation of the bridge preservation strategy at TxDOT?

The sheer magnitude of the number of bridges in Texas represents the main challenge in the implementation of our long-term goal to reverse the trend of bridges in “fair “condition.  We have to deal with financial constraints and limited resources that do not match such a massive inventory.

A major implementation challenge also entails convincing our own Districts to dedicate some of their resources to cyclical bridge maintenance. We can strive to build bridges that are as maintenance free as possible, but at some point cyclical maintenance is necessary in order to extend the life of a structure. Cyclical maintenance does not cost much and it is really effective keeping small problems from becoming big ones. We know, for example, that if we do not take care of relief joints in approach slabs, the abutments will start pushing on the bridge ends, which is a major problem. Joint repair, clearing drains, cleaning caps’ tops are examples of cyclical maintenance at TxDOT.

With so much focus and resources on maintaining pavements, it is challenging to bring the attention of the Districts to bridges and convince them to think about bridges in the same way as they do about pavements.

Pavement problems are always front and center for Districts, while bridge problems are usually less visible. Since pavements and bridges are part of the overall asset, there should not be a dividing line between them.  

Management of pavements and bridges runs on two parallel yet separate tracks to the point that there are different pavement and bridge maintenance crews. I think that pavement and bridge practitioners should work together on preservation issues.

Is TxDOT involved with off-system bridges?

Yes, we inspect them and we financially support their replacement. If there is a critical finding or a closure is going to happen, we then get involved with the owner–the county, municipality, or city—to determine what needs to be done.

Overall we have far less control of the off-system bridges in comparison with the on-system bridges. We also are not involved with the maintenance of off-system bridges. It is up to the local owners to maintain these bridges.  There is little, if no, maintenance for off-system because of limited resources for a large number of bridges.

Is TSP2 helping reach your goals?

What I like of  TSP2 is that it is getting us all together and giving us an opportunity to talk about things that are working and not working with bridge preservation.

While so much of the focus nationally is on data collection to the point that we are dealing with data overload to some degree, TSP2 is refreshingly down-to-earth since it focuses on the nitty-gritty details of bridge preservation.

In a conference like this (SEBPP ed. note) we sit with consultants, suppliers and contractors exchanging information. There is always something that we can bring home and make use of.

What can TSP2 do to improve its program?

Maybe TSP2 can find ways to keep bridge preservation practitioners connected during the year through webinars and conference calls so as to build on the annual conference. Sharing information through websites and social media is effective, but there is nothing like putting a date in a calendar and attending a meeting, even if it is simply by web connection.

Our TSP2 SEBPP committee core group has already implemented a strong communication process with calls once or twice a month. We should consider improving communication beyond our core group by increasing the amount of time that bridge practitioners from different states talk with each other and exchange information.

 

LINKS

Report on Texas bridges:

http://www.txdot.gov/government/reports/texas-bridges.html

Bridge Facts:

http://ftp.dot.state.tx.us/pub/txdot-info/library/pubs/bus/bridge/facts-16.pdf

Posted in Interview

A conversation with Keith Kesner about the new ACI 562-16 Concrete Repair Code

Keith Kesner

Author: Lorella Angelini, Angelini Consulting Services, LLC

I met Keith Kesner at a monthly educational meeting organized by the Minnesota Concrete Council (MCC) in St. Paul, MN, when he gave a very informative presentation about the American Concrete Institute (ACI) 562: “Code Requirements for Assessment, Repair, and Rehabilitation of Existing Concrete Structures and Commentary”. I then contacted Keith in order to know more about the new Code and its potential use for bridge preservation.

Keith, the chair of the ACI 562 Committee, is a registered Professional Engineer in several States. He has over 20 years of experience as a structural engineer and he has written over 100 publications on a variety of structural engineering topics. He works as a Project Manager with CVM Professional in King of Prussia, PA, a Consulting Engineering firm that specializes in the evaluation and rehabilitation of existing structures.

Founded in 1904 and headquartered in Farmington Hills, MI, ACI is a leading authority and worldwide resource for the development and distribution of standards, technical resources, educational training and certification programs related to concrete design and construction. ACI has over 95 chapters, 110 student chapters, and nearly 20,000 members spanning over 120 countries.

Could you speak of the goals of ACI and introduce the ACI 562 Concrete Repair Code that you chair?

ACI is an international organization with the objective of developing and distributing knowledge on concrete design and construction. Some of the key goals of the Institute include the development and maintenance of standards and consensus documents for the design, construction and repair of concrete structures.

People are probably most familiar with ACI 318 Building Code, which is the US Standard Code for reinforced concrete construction. ACI 318 is also very heavily used internationally.  ACI has produced a wide variety of other documents, such as specifications and procedures for concrete construction in different types of environment, from hot to cold weather, development and standards for the use of Fiber Reinforced Polymer (FRP) materials and the repair of concrete structures.

ACI has much wider reach than what people are most familiar with, which is ACI 318.  It is a very large organization that covers all aspects of concrete construction.

Who are the professionals that are part of the ACI membership? Does ACI mainly gather Consulting Engineers?

Consulting Engineers are a prominent presence in ACI, but other groups of professionals are also strongly represented in the Institute. These groups include cement producers, concrete producers, manufacturers of construction products, contractors focusing on concrete construction and repair, and academics involved with research on the design and construction of reinforced concrete structures. ACI has a very broad-based membership that touches all aspects of the concrete industry.

What are the key elements of the new ACI 562-16 Code?

The ACI 562 Code was developed to be a parallel document/Code to ACI 318. Whereas ACI 318 deals with new building construction, ACI 562 was developed specifically for the repair of existing concrete buildings. It was also designed to work with the International Existing Building Code (IEBC).

ACI 562 was designed to be a performance-based code with prescriptive requirements when required. It basically provides design professionals with code requirements for the assessment of existing concrete structures and then, depending upon the results of the assessment, procedures for the design of appropriate strategies for the repair, including durability requirements.  The code also calls for future maintenance and monitoring requirements to be documented by the licensed design professional for the owner.  However, ACI 562 cannot mandate that actual maintenance be performed.  

Is ACI 562 a new Code?

Yes, ACI 562 is a completely new Code. The first edition was published in 2013. The current ACI 562-16 edition, which was published last year, is an update of the 2013 version. So we are currently on the second version of the Code.

Is the 2016 update significant?

Yes, the Code was updated significantly from 2013.  We made a lot of changes to the terminology to make it consistent with documents published by other standard developing organizations. We added code requirements and commentary on these requirements to better define the level of repairs that may be required on existing structures. We worked on better integrating the Code with IEBC requirements.  We also spent a lot of time working on requirements for the bond of the repair material to the existing structure.

A major update entailed the introduction of the concept of “demand to capacity ratio” in order to better delineate the extent of the repair that may be required in a building.  As an example, let’s suppose that we have a beam with a load of 100 kips, as specified by the building Code. If after evaluation we find out that the capacity of the beam is, let’s say, 80 kips, we can calculate the demand to capacity ratio by dividing 100 by 80 = 1.25.  Being the ratio  greater than 1, the beam requires strengthening and the repair must be designed in order to provide the amount of strengthening that will bring the ratio back to or lower than 1.00.

In summary, the “demand to capacity ratio” represents a measure of how deficient the structural element is and therefore it is a measure of the amount of strengthening that needs to be added to the structural element in order to satisfy Code requirements.  

Does the Code include guidelines on how to evaluate the capacity of a concrete structural element that has deteriorated over time?

Yes, this information is contained in Chapter 6 of ACI 562, which deals with how to do the evaluation of a deteriorated structural concrete element. There are a lot of documents that have been published on the evaluation of existing concrete structures, which are referenced in the commentary to the Code. Design professionals using the Code can look up to these documents and can get additional information on how to evaluate the current capacity of existing concrete structures.

Where did the need for the new ACI 562 Code stem from?

The need was really recognized by people involved with the concrete repair industry, who realized that repairs on existing structures were not performing adequately. A thorough investigation was carried out by a couple of different groups: the US Army Corps of Engineers and the Building Research Establishment (BRE) in the UK. Both reports (see linkage, ed.) concluded that repairs of concrete structures were failing at a high rate. Improved repair techniques providing better performance of repairs were needed in order to avoid repair of previously repaired structures, which is obviously a waste of money.  

By creating a standard for the repair of building structures we responded to a recognized need in the concrete repair industry and made a significant progress in the direction of improving the performance of repaired concrete structures. In addition, by introducing the “demand to capacity ratio” concept, we provided a tool for achieving a consistent level of reliability for repaired concrete structures.

It is likely that what you said about repairing repaired structures also applies to the DOT experience with concrete repair. In fact DOTs have started focusing on preservation practices based on cyclical and preventative maintenance, which do not require major concrete repair applications.  How could ACI 562 be of help to bridge preservation practitioners?

The ACI 562 Code was specifically developed for building structures. A direct translation of many of its parts to bridges would not work since loads and resistance factors are different in bridges compared to buildings. However, the performance-based concepts that were used in the development of the ACI 562 Code can be appropriate for bridge structures.

Information included in Chapter 8 – Durability could be of particular benefit to bridge preservation practitioners. When we talk about durability of a repaired concrete structure we must consider the durability of the original structure, the durability of the repair, and the interaction between the repaired area and the original structure. This holistic approach to concrete repair underscores the fact that it is not sufficient to just have a durable repair or a durable portion of the original structure but it is the whole system that needs to work together.

A lot of the problems with durability of repairs relate to the addition of new materials, that have different electrochemical properties and stress-strain response than the existing materials. We must predict how these new repair materials are going to interact and respond when they are applied to the original structure. The comprehensive concrete repair concept will likely fit with current practices adopted within bridge preservation as part of an asset management program.

Would ACI consider the possibility to collaborate with TSP2 for the development of a performance-based specification for concrete repair?

Yes, absolutely. I would also suggest looking into ACI 365 Committee – Service Life Prediction, which is working on developing service life prediction standards and procedures for concrete structures. Some of the work that has been already done by the 365 Committee may be of great interest to engineers and practitioners who deal with bridge preservation.  

ACI Committee 563 is also in the process of developing specifications for repair of existing concrete structures.  The concrete repair specifications should be completed in late 2017 or early 2018.  

 

LINKAGE

ACI Vision 2020—Repair/Protection Council

http://www.concretesdc.org/projects/Vision_2020.htm

The Condition of Corps of Engineers Civil Works Concrete Structures, Technical Report REMR-CS-2, 1985, 133 pp.

Building Research Establishment (BRE): Thematic Network on Performance-based Rehabilitation of Reinforced Concrete Structures      

http://projects.bre.co.uk/conrepnet/pages/default.htm

ACI 562 from Structure Magazine

http://www.structuremag.org/?p=5454

LIFE-365 SERVICE LIFE PREDICTION MODEL

https://trid.trb.org/view.aspx?id=729747

Posted in Interview

A Conversation with Bill Oliva, Chief of Structural Development for Wisconsin DOT

bills-picture

Bill Oliva (WisDOT)

Author: Lorella Angelini, Angelini Consulting Services, LLC

Bill Oliva is a recognized leader in bridge preservation and asset management at both the national and State level. He is the Chief of Structural Development for Wisconsin DOT (WisDOT) and participates in the activity of the AASHTO Subcommittee on Bridges and Structures T-11 Research, TRB AFH40 Construction of Bridges and Structures and TRB Sub-committee on Accelerated Bridge Construction.

Could you talk about your responsibilities with WisDOT?

As the Chief of Structural Development for WisDOT Bureau of Structures, I oversee the development of policies, standards and automation. I am also in charge of bridge management and asset management, rating and permitting of bridges.

Previously with the Department I was bridge structural engineer, lead hydraulic engineer and I served for 10 years as a project development supervisor in our regional office. I was fortunate that I was given the opportunity to have a broad perspective on WisDOT activities and to relate them to the different business functions.

What does bridge preservation entail at WisDOT?

It entails many aspects from investment strategy to technology development with the common aim of building consistent expectations and goals that will apply to preservation of WisDOT infrastructures.

Building awareness about the challenges that we at the WisDOT face with maintaining the bridge inventory is a key element of bridge preservation. It essentially boils down to risk to operations, which means our ability to operate the transportation facilities without risk for the public.

If we have to close a bridge because some aspects went out of control, such as conditions that deteriorated the bridge to the point that no longer can carry loads, this interferes with our operations and the use of the bridge by the public. People expect to go from point A to B at their desire, without delay or inconvenience. In my opinion a lot of what we do with bridge preservation is really aimed at insuring our ability to maintain infrastructure operations.

Bridge preservation also helps maximize benefits from the investments we make, taking into account we do not have enough money for the many different needs that we face.  The way funds are applied in order to achieve maximum benefits and risk control is what bridge preservation means to me.

Some people look at bridge preservation from the financial aspect, i.e. maximize life-cycle cost and investments, but this other element, operations, sometimes slides under the radar screen while it is actually one of the major components of bridge preservation. By maintaining awareness through inspection and applying the appropriate treatment early, whether through preservation or maintenance, we are controlling operation risk.  Closing infrastructures is more than an inconvenience for users, it is an issue related to safety.

Can you speak of the bridge preservation strategy at WisDOT?

Our strategy stems from some of the changes we are all going through with MAP 21 and FAST Act, which mandated changes that represent opportunities to do things differently and perhaps better.

With regards to the new AASHTO inspection elements, we decided to use our already good inspection program in a broader way, as the foundation of a concept strategy that will allow us to maintain bridges in a more systematic manner. Inspection data are at the core of WisDOT 2016 Bridge Preservation Policy Guide (see below), which was developed with contribution from national experts, our own staff as well as regional bridge practitioners. The Policy Guide, which sets out the framework for performance goals for bridges, NBI and element level goals, created a series of work rules for different actions that must be taken for bridge preservation.

By combining inspection information with work rules, the Policy Guide indicates specific needs for actions related for example to the deterioration of concrete deck, steel girder, expansion joints or bearings. It provides a structured approach to problems, thereby avoiding subjectivity and inconsistency.

The next effort at WisDOT will entail upgrading to our bridge management system as well as developing an asset management program, which all lead to the ability to systematically identify work needs and provide means to establish projects and bridge programs.  Deterioration capabilities are key elements since we want to be able to look out in the future and predict our needs in 5 – 20 years based on current conditions.

Could you elaborate on the work rules?

In a nutshell, the inspection program, the preservation policy, the automation bridge management system all lead to the implementation of a data driven program, which connects information from different sources and provides work rules.

I would like to add that this interactive program can be very helpful to the younger staff, who will not have to spend years of learning before they are able to make decisions and implement actions.

What challenges are you facing in the implementation of the bridge preservation strategy?

In addition to the fact that we have limited dollars to support the program, there is need for more research in certain areas.

We have a good understanding of some mechanisms that influence the deterioration of bridges and how some of the treatments help but there is quite a bit of variability.  We need more confident estimates of when it is time to redo preservation applications, for example, bridge deck overlays and penetrating sealers.

We have a lot of interest in deterioration curves which can allow the optimization of investments and performance.

While different strategies can be used throughout the life-cycle of a bridge, our challenge is to research and adopt the optimal strategy for our environment. Technologies that work in a different climate can very likely be of no use to successfully maintain the 15,000 bridges of the state of Wisconsin.

Is there any bridge preservation success story you would like to share?

Probably the development of our Bridge Preservation Policy Guide and some aspects of our automation systems related to bridge management.

We made a lot of upgrades with our bridge management system supporting the use of mobile devices to do bridge inspections. We can currently conduct a bridge inspection through an I-Pad or a smart phone, which allow downloading information and uploading inspection results. If something critical that can compromise the loading carrying capability of a bridge is found, the bridge rating engineer is alerted almost immediately from the field. The engineer can therefore provide instructions for further information when the inspector is still in the field.

What are the goals of your department in 2017 and as well the long term?

Moving forward we want to do further implementation of our asset management investment process. While it is one thing to build technology and rules, it is a different thing to integrate them into the business process. We are working with investment people and regional people making sure they understand the tool we have and have the opportunity to tell us what they need from it.

I am looking forward to continue working with the TSP2 Partnership in order to try building more uniformity and consistency between Midwestern States in practices, details, policies and specifications, where appropriate and applicable.

Reaching a certain level of consistency between States that share similar climate can bring significant benefits to both DOTs and to industry. As an example, if contractors can work easily in more than one State, they have more opportunities for business while DOTs can benefit from increased competition. Contractors are currently fairly localized to one State since they have to learn new sets of information and rules as they move from one State to another.

The TSP2 Partnership plays a very important role in facilitating dialogue and exchange between DOTs and industry.  While at DOTs we sometimes see ourselves in a mirror, industry can provide insights across the borders and suggest higher level of uniformity in specifications, guidelines and approved product lists.

 

LINKAGE

  • WisDOT 2016 Bridge Preservation Policy Guide

http://wisconsindot.gov/dtsdManuals/strct/manuals/preservation/wisdot-prsv-pol.pdf

  • Wisconsin DOT Bridge Asset Management presentation by Bill Oliva at 2016 MWBPP Meeting in Milwaukee, WI

http://pavementvideo.s3.amazonaws.com/2016_MWBPP/4_Wisconsin%20DOT%20Bridge%20Asset%20Management_Oliva.pdf

Posted in Interview

Is the Practice of Bridge Preservation Heroic?

Author: Lorella Angelini, Angelini Consulting Services, LLC

A recent article published in The New Yorker magazine draws a parallel between the practice of incremental care in medicine and the preservation of bridges and infrastructures.   

The author, Atul Gawande, characterizes these two practices, incremental care and preservation, as “heroism of the incremental”. They are both based on the concept of implementing policies that focus on a steady flow of repetitive actions rather than reacting on short notice to specific and often dramatic problems. The incremental approach has been proven to be economical and effective, especially in providing long term benefits. The author points out that with today’s technology, incremental practices can take advantage of the latest available tools, especially in the areas of tracking, planning and communication. At the same time Gawande underscores the fact that incrementalism is chronically lacking of funds, which may be related to the fact that its approach is not considered “heroic”, meaning that it does not produce “immediate and visible success”.  

I cannot be more in agreement with the idea of incrementalism as it is described in the article. Incrementalism is based on a different mind-set than the reactive approach usually driven by an emergency. But it is still “heroic”. It only requires another type of hero, one far from the limelight, who works day after day to either provide care for people or maintenance to structures.    
http://www.newyorker.com/magazine/2017/01/23/the-heroism-of-incremental-care

Posted in General, General News

A Conversation with Nancy Huether Transportation Engineer with North Dakota Department of Transportation

Employee Portrait of Nancy Huether - Bridge Division

Nancy Huether (NDDOT)

Author: Lorella Angelini, Angelini Consulting Services, LLC

At the recent TSP2 MWBPP meeting in Milwaukee I met Nancy Huether, Transportation Engineer with the North Dakota Department of Transportation (NDDOT), who is the chair of the TSP2 Midwest Bridge Preservation Partnership Board of Directors.  I had a chance to speak with Nancy about bridge preservation strategies and implementation challenges in her state.

What does bridge preservation entail at NDDOT?

The bridge preservation program at NDDOT is still being defined. It is a given that focusing on bridge maintenance is one of our main goals. However, bridge preservation should be considered during all phases of the life of a bridge from conscientious design and construction to timely rehabilitation.

I believe strongly that bridge preservation starts with design and construction, which are critical elements in making sure we have good bridges and we can maintain them.  In other words, it is challenging to maintain bridges if they are not designed properly or constructed according to specifications.

I understand the design part. Could you tell me more about the construction aspect? Do you mean choosing the right materials and applying them correctly?

Yes, proper construction is very important. For example, when placing concrete it is important to consider ambient conditions such as temperature, wind, and humidity. Proper curing is also a critical component in ensuring long-lasting well-performing concrete.

I would like to reinforce the concept that preservation entails more than just maintenance. Construction plays a big part and cannot be overlooked.

Could you also speak of the design part? 

Using design methods that minimize maintenance is critical.  For example, the bridge division has been designing bridges for many years with integral abutments that minimize or eliminate the need for joints and the maintenance headaches that come along with them.

I understand that you have been in your new bridge preservation management position for about one year. Can you speak of this appointment?

I am a Registered Professional Engineer in the Bridge Division.  Just over a year ago, I was tasked with switching from the Hydraulics Section to the Structure Management Section to start a bridge preservation program.

Prior to my appointment, the NDDOT had no formal bridge preservation program.  That is not to say preservation concepts were not understood and considered, but there was no formal program. Bridge Preservation only entailed the Bridge Maintenance section that was added to the Maintenance Operations Manual in 2008.  This section, which was developed with the help of Bridge and District employees, laid out maintenance tasks and a schedule for completing those tasks.

What is your role with the Districts?

I do not supervise the implementation of bridge preservation in the eight Districts of the NDDOT.  My role is to support the Districts in their efforts by assisting with requests for education or by providing information about bridge preservation materials and procedures.

Encouraging Districts to focus more on bridge preservation activity and understand its value is one of my main goals. For this reason, as soon as I got the new bridge preservation assignment, I went to visit each District and learn about what they were doing.  The amount of bridge preventative maintenance being done in the eight Districts varied from a lot to very little.  The NDDOT is fortunate to have very capable maintenance personnel and I am confident that with additional support they can do much more.

What have you done so far?

I am in the process of developing the bridge preservation program. The first step of the program, which is nearly complete, is updating the Bridge Maintenance section of the Maintenance Operations Manual with current materials and best practices. We want to give more value to the Manual and see bridge maintenance operations more fully adopted by all the Districts.

The second step of the program entails finalizing a bridge preservation strategy that will eventually include not only maintenance, but also design, construction, and rehabilitation.

What is the major challenge that you are facing?

One major challenge involves getting more of the District personnel to better understand the benefits and importance of bridge preservation.  Since the NDDOT does not have dedicated bridge maintenance crews, bridge maintenance is only one of the many maintenance tasks the District Maintenance Sections are responsible for completing.

The bridges in North Dakota are in fairly good condition. However, sometimes when bridges are in need of repair, maintenance is deferred until small problems become bigger problems and contractors are called on to do the work.  This is a reactive mode of action.  Embracing the preservation concept means focusing on preventative maintenance and taking care of small problems before they become big problems. Increasing the awareness and benefits of pro-active maintenance will help us keep our good bridges good.

Do you have a bridge preservation success story you would like to share with the readers?

Yes, it is about the pro-active actions taken by one of our Districts. Approximately two years ago a District employee who has always had a keen interest in bridge preservation, was put in charge of maintenance for that District, where little bridge preventative maintenance had previously been done.

Under the guidance of this employee, the District has implemented a bridge deck preservation program that includes sweeping and washing the deck, sealing cracks with epoxy, and applying a silane surface treatment.

Although prescribed in the Maintenance Operations Manual, silane sealers had never before been applied by NDDOT maintenance crews.

The District developed the silane surface treatment application equipment and process on its own. It encompassed designing, assembling, and calibrating the spray equipment including spray bar, nozzles, tractor, pump and tank. They successfully treated several bridge decks this year.

At what time do you apply silane sealers as a bridge deck protection?

We apply the silane deck surface treatment as part of the initial construction, as soon as the bridge deck is completed and the concrete is cured. In doing so, the application becomes part of the design and the construction project.  We then prescribe the reapplication on a 6 year cycle.

Could you talk of your goals for 2017 and the upcoming years?

I have two main goals. The first is to assist our maintenance forces to continue taking initiatives and doing new maintenance activities in line with pro-active bridge preservation.  My role is to support them with information about products, processes, training, tracking, and any other areas needed, to the best of my ability.  This support, combined with their extensive knowledge and field experience, will help us achieve this goal.

My second goal is to get NDDOT bridge preservation program well documented, funded, and solidified.  The program will define the overall purpose of bridge preservation and outline key elements such as objectives, performance measures, and goals that support the NDDOT Strategic Business Plan. This program will also define a systematic approach to project selection and provide guidance for appropriate preservation strategies.  A well-defined bridge preservation program is important in cost effectively managing and preserving the NDDOT’s bridges.

Can TSP2 help NDDOT reach its goals? Is there more that TSP2 can do for you?

TSP2 continues to play a significant role in developing our bridge preservation program. I regularly use the information that is available on their web site.

TSP2 Regional and National Partnership Meetings are also of great value. They have given me, as well as others at the NDDOT, the opportunity to make connections with bridge preservation experts at other State DOTs, as well as with industry members, consulting engineers and contractors.

It is truly invaluable to be able to talk to people in other states about what they are doing and what has worked in solving specific bridge preservation problems. Thanks to TSP2 and the bridge partnerships, I have a large group of knowledgeable peers I can reach out to when questions or issues arise.  I can send one e-mail and receive 20 replies.

There is always something more that can be done. My hope is that TSP2 continues to strengthen its role as collector of information.  The TSP2 web site should be the first place people can go to find information, research, and publications about bridge preservation.

Posted in Interview

A Conversation with Pete Weykamp about LTAP

pw-for-tsp2
Pete Weykamp at LTAP Conference, Purdue University

Author: Lorella Angelini, Angelini Consulting Services, LLC
After leading the bridge preservation program with New York State DOT, Pete Weykamp has put his knowledge and experience at the service of the Local Technical Assistance Program (LTAP). Together with Ed Welch, Bridge Preservation Engineer for the AASHTO TSP-2 Program, and with the support of the National Center for Pavement Preservation (NCPP), Pete has started the Bridge Preservation LTAP training track for Local Agencies. I reached out to Peter in order to know more about the program. Additional information is reported in the flier, see linkage at the end of the post.

  • Could you speak of the reasoning behind the newly introduced Bridge Presevation training?

Over the last few years there has been great interest in getting Local Agencies (Cities, Counties & Towns) “up to speed” on the maintenance and preservation of their bridges.  In response to these needs Ed Welch and I have developed and implemented an Introductory/Grass Roots Bridge Preservation LTAP course for Local Agencies. The course is focused on the concept of bridge preservation and the advantages that it generates. It can be tailored to individual audiences adding or dropping topics depending on their capabilities and needs. The course can be presented as a full or half day as time permits.

Understanding the need for training and the development of municipal programs specific to the preservation of the non-State owned bridges is vital to the overall condition of the Country’s 608,000 bridges.  An effective/balanced bridge preservation program should include all aspects of preservation, first and foremost both reactive and proactive maintenance.

  • What is the target audience for the training program?

Our target audience consists of bridge maintenance personnel working for Local Agencies.  We have the ability to modify the training sessions based on the make-up of the different audience groups.  For example, for an audience of county highway supervisors and engineers we focus on Why specific preservation actions are necessary.  For an audience made up of field crews, a greater focus is place on How the actions are performed.  

  • Can you speak of the short and long term goals of the program?

Short term goals focus on a holistic approach to managing highway structures at the local level.  This includes topics that are essential for the preservation of locally-owned highway structures, such as involving industry partners and formalizing a process to deliver needed training.  

Longer term goals create a mechanism for local officials and crews to network, view hands-on demonstrations, and provide opportunities to participate in the AASHTO Regional Bridge Preservation Partnerships.

  • What is your specific role?  

My role is to develop training modules and provide instruction to for local agency training.  Working with Ed, we created training modules on Concrete Washing and Sealing, Expansion Joints, Repairing Concrete, Programming Bridge Maintenance, Developing a Bridge Preservation Program, and an overview presentation on Bridge Preservation Training for LTAP.  

I am currently working on training modules for Steel Coatings, Bolting, and Bearing Maintenance.  The modules will include videos and demonstrations.  I will continue to seek the assistance of industry partners in developing the training modules.  

  • How much was implemented in 2016 and what is expected in 2017

During the current year, training modules on Concrete Washing and Sealing, Expansion Joints, Repairing Concrete, Programming Bridge Maintenance, Developing a Bridge Preservation Program, and an overview presentation on Bridge Preservation Training for LTAPs were developed.  

In October, Ed and I conducted a training session during an event hosted by the Indiana LTAP through Purdue University.  Approximately 100 county highway supervisors participated in sessions on Expansion Joints, Programming Bridge Maintenance, and Concrete Repair.  An industry representative conducted a demonstration on the use of chemical anchors.  The half-day of bridge preservation training was received with substantial interest.    

For 2017, additional modules on the Protection of Structural Steel, Deck Overlay Options, Scour Remediation, and the Use of Sacrificial Anodes will be created. TSP2 will continue to outreach to Local Agencies offering bridge preservation training and the resources available through its program. TSP2 will also continue to explore needs and applications suitable for bridge preservation actions that can be implemented at the local level.

 

LINKAGE:

LTAP National Program

National LTAP & TTAP Association

Indiana LTAP – County Bridge Conference

Bridge Preservation Flyer for the LTAP Program

Posted in Interview