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43 Table continued from p.42 Respondent Website Address South Carolina Refer to subsection 814 for policy for list Tennessee (pp. 4243; QPL 2, Section A) (PDF pp. 194197 or Standard Specifications pp. 521524) Utah Specification No. 07105 Waterproofing Membrane Virginia Washington http://www/ Material General Special Provision (GSP) 6-08.2(9- 11.2).OPT1.GB6 Wyoming See SS-500C at supplemental_specifications Alberta Construction Specifications: Drawing: Manitoba Standard Construction Specifications: (currently being updated) Approved Products List: New Brunswick 2006 Standard Specifications: Summary of revisions in 2011: Newfoundland and Labrador rock-membranes.aspx Nova Scotia Division 5 Section 9 Ontario Waterproofing membrane: asp?MPICatId=7917BE45-79CB-4CB5-86BD-0CE9204B7EA0 Protection board: asp?MPICatId=49C888F0-499F-48ED-9DA2-C9120CFF6063 5. CRITERIA 8. Does your agency have criteria for when waterproofing membranes are used? Yes No New Bridge Decks 17 15 Existing Bridge Decks 20 13 If the answer to either of the above is Yes, please provide the criteria. Respondent New Bridge Existing Criteria Decks Bridge Decks Alaska Yes Yes If an asphalt overlay is used, a waterproofing membrane is specified where possible. California Yes Yes In freeze-thaw areas only under the following circumstances: Used on sidehill viaducts. Used to avoid a drastic profile change when there is a thick AC overlay on an existing bridge deck that requires replacement. Connecticut Yes Yes Most bridges in Connecticut are constructed with membranes and bituminous concrete overlays. Idaho Yes Yes Depends upon what we are trying to achieve. Illinois No Yes Not allowed anymore on interstate bridge unless replacing in-kind, not to be used on bridges with ADTs over 10,000. Kansas No Yes We don't use membranes on new decks and I don't think we are going to do so anytime soon. When we have a bridge that has a bad deck that should either be re-decked or the entire bridge replaced and no available funds are currently available, we consider placing a waterproofing membrane with a 2-in. thick asphalt wearing surface as cover to maintain rideability. Of the 30 we have placed since 1994, 25 are currently in place and the other 5 were on bridges that have since been replaced or re-decked. Table continued on p.44

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44 Table continued from p.43 Respondent New Bridge Existing Criteria Decks Bridge Decks Michigan No Yes When deck surface has more than 10% deficiencies and deck underside has more than 10% deficiencies and we need to extend the life of the deck by no more than 10 years. See the Deck Preservation Matrix for more detail at MDOT_BridgeDeckMatrix_182438_7.pdf Spec Book public/specbook/ pg 461. Missouri Yes No Waterproofing membranes are currently used only for new construction using adjacent box beams or cored slabs that utilize an asphalt wearing surface. These bridges are constructed on roads with ADT < 1,000. MoDOT has increased its use of this structure type since 2009 as part of an initiative to improve rural bridges, many of which have ADT < 1,000. As such, MoDOT does not have a long track record with membranes. MoDOT has not con- structed membranes on concrete bridge decks since the 1994 cutoff date for this survey. Nebraska Yes Used on deteriorated decks with NBIS condition 5 when the chloride content is mini- mum and asphalt overlay is practical. New Hampshire No No We use them as standard practice. Oregon Yes Yes tion_1-2004_apr10.pdf Pennsylvania No Yes Pub. 15 M Design Manual 4 - Part A Section 5.5.2 pg A.5-25 and 5.6 pg A.5-60 Link = South Carolina Yes No Waterproofing membranes for cored slab spans. South Dakota Yes Yes Waterproofing membranes are typically not used on new bridge decks. There was a pair of decks on the interstate where subsurface soils were causing approach roadway rideability problems. In that case, an asphalt overlay was placed on the new bridge decks to provide options for future profile adjustments to maintain a smooth ride. Waterproofing membranes with asphalt overlays are typically used on bridges/decks nearing the end of their service life. The asphalt overlay in that case serves as a good riding wearing course and provides some additional load distribution and buffering to the deteriorated concrete slab underneath. In these cases, the bridge/deck is expected to be replaced in 10 to 15 years following the overlay. Tennessee No Yes All resurfacing projects where bridge deck repairs are needed as a cost-effective way of waterproofing the repaired bridge deck. Utah No Yes Waterproofing membranes are standard practice when applying asphalt wearing surfaces on any existing deck. The combination of membrane and asphalt overlay usually occurs when a deck requires pothole patching. Virginia Yes Yes Asphalt overlay is to be placed on the deck. Washington Yes Yes All existing structures with asphalt and in the rare cases where asphalt is specified for new structures. Alberta Yes Yes 1. All new bridges with cast-in-place decks. Section 17 "Deck Protection and Wearing Sur- face" of the Bridge Structure Design Criteria. 2. For all existing bridge decks when addi- tional dead load imposed can be accommodated. New Brunswick Yes Yes All concrete decks are to be protected by a waterproofing system. Newfoundland Yes No Used on all new and full slab replacement projects. and Labrador Ontario Yes Yes Waterproofing membranes are used on all new and existing decks, as a standard policy. Membranes on existing decks are removed and replaced periodically to maintain deck protection. Prince Edward Yes No All new decks shall be waterproofed unless load restrictions prohibit additional asphalt Island dead load on existing bridges with new decks.

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45 9. What are the expected service lives in years of the waterproofing membranes that your agency has used? Percentage Response 10. What is the basis for the answers to the previous question? Respondent New Bridge Existing Basis Decks Bridge Decks Alaska 16 to 20 11 to 15 If properly installed, asphalt deterioration typically governs membrane service life, 1015 years. On new bridges, a 4-in.-thick overlay is typically used and may extend the service life, whereas on existing bridges less than 4-in. thick may be provided depending on the load rating, which may reduce the service life. Further, existing bridges may have deck damage that may also reduce the expected service life. California 6 to 10 6 to 10 Expected life of an AC overlay in a freeze-thaw area. Connecticut 16 to 20 16 to 20 The membrane will typically last approximately two paving cycles of about 10 years each on heavily travelled roadways. A partial depth milling, leaving the membrane intact and repaving is done at the end of the first overlay cycle. The membrane and overlay are typi- cally removed and replaced in whole at the end of the second paving cycle. Idaho 6 to 15 6 to 15 Experience. Illinois 11 to 15 11 to 15 Past experience. The membrane only lasts as long as the bituminous wearing surface on top of it. Kansas 0 to 5 Past performance and the condition of the existing deck that we are covering. We have only used waterproofing membranes as a last resort. They provide extended rideability for a deck that is in very bad shape. Usually in these situations, some full depth patches have to be completed before placement to prevent holes from developing. The plan is usually to extend the deck life for one to four years until funds become available for either a deck or bridge replacement. We have seen them perform for as long as 10 years. When one goes bad, the deteriorated condition of the covered concrete can accelerate. They trap water as well as they stop it when falling. Michigan 6 to 10 The Deck Preservation Matrix referenced in the answer to Question 8. The expected ser- vice life varies based on the initial deck condition. Experience. Missouri 16 to 20 It is anticipated the membrane will last as long as the asphalt it is beneath. Table continued on p.46

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46 Table continued from p.45 Respondent New Bridge Existing Basis Decks Bridge Decks Nebraska 11 to 15 We use asphalt overlay when the life of the deck is near its end and we need to extend the life of the deck by 10 to 15 years before redecking the bridge or major deck rehabilitation with structural overlay such as silica fume. Asphalt life is about 10 to15 years. So we expect the life of the membrane to exceed the life of the asphalt. Our experience tells us it's hard to replace the asphalt overlay without damaging the membrane. New Hampshire 11 to 15 11 to 15 This is an estimation, as we do not have any with 15 years of service life yet. The basis (optimism) for this answer is that we frequently had good luck with peel-and-stick, although some of those debonded. The bond with the torch applied is superior, since the liquid asphalt is worked into the concrete surface. New Mexico 0 to 5 0 to 5 From talking with the districts that have used them. Their experience has been that they do not work well. New York Depends on the condition of the existing deck and the overlay placed. Membranes will last as long as both are performing. Oklahoma 16 to 20 6 to 10 Approximations based on visual observation. Oregon 16 to 20 16 to 20 We have no basis except anecdotal observations. The range given is about the longest we have seen them be effective. We have seen a few that have been improperly installed that are not effective for even a couple of years. We now require a performance test after instal- lation to show they are at least effective immediately after construction. Pennsylvania > 25 Research report that an estimated life is 40 years or more. South Dakota 16 to 20 11 to 15 Experience. Tennessee 6 to 10 Life expectancy of asphalt. Texas 11 to 15 The surface treatments are applied when the deck has lost its skid numbers. Also, surface treatments are applied to bridge decks when the approach roadways are being surface treated and asphalt overlaid. Utah 6 to 10 6 to 10 Our membranes usually only last about the life of the asphalt applied, which is on average 8-10 years. We applied a few spray-applied waterproofing membranes in 20072008 on a trial basis. These products have warranties for the life of the bridge, but we are too early in the evaluation to make a judgment on their performance and durability. Virginia 16 to 20 16 to 20 The asphalt surface mix will last approximately 10 years and the base mix will last at least 20 years. Resurfacing at 10 years without damaging the membrane gives a 20 year life. The membrane can last 20 to 30 years so a life > 25 years is possible, but I would use 20 years for design and LCC analysis unless we have better data to indicate a longer life. Washington 21 to 25 21 to 25 Performance of membranes has yet to be proven. WSDOT assumes a reasonable perfor- mance through one paving cycle of 20 to 25 years. WSDOT also has a method of data col- lection to measure the performance of membrane systems, but the results will not be avail- able for many years. Wyoming 11 to 15 Experience, typical life for an overlay on a bridge deck. Alberta > 25 > 25 Waterproofing membrane has been used by Alberta Transportation for over 25 years with very good performance. Manitoba 16 to 20 16 to 20 Expected service lives are based on the anticipated life expectancy and effectiveness of the waterproofing membrane. MIT is beginning to move away from waterproofing membranes and asphalt overlay systems to exposed concrete decks on our bridges due to deck perfor- mance enhancements realized by using fibre-reinforced concrete. Ancillary benefits are reduced dead load and/or increased structural capacity of the deck and better long-term per- formance of the riding surface (less rutting in wheel paths and potholes at joints). New Brunswick 21 to 25 21 to 25 Deck surface partially milled and resurfaced at 1215 years, but membrane and full-depth resur- facing not expected to be replaced until 2025 years; built in to our asset management system. Newfoundland 16 to 20 16 to 20 Ideally this would be the life of the asphalt pavement. Have in past year started to use and Labrador greater asphalt thickness on decks. This might allow for rehabilitation of asphalt surface without damaging waterproofing system. Nova Scotia 16 to 20 11 to 15 Experience has shown these products tend to last in our climate with our traffic loadings. Ontario > 25 > 25 An internal study was carried out, examining decks up to 17 years old, which confirmed the effective functioning of the membranes and resulted in an estimated service life of more than 25 years. We have done chloride tests to verify performance after 1520 years. End result specification would ensure consistent quality of waterproofing. Prince Edward 16 to 20 6 to 10 Experience. Island Quebec 16 to 20 16 to 20 Experience. Saskatchewan 16 to 20 16 to 20 Historically removed waterproofing that was 17 to 20 years old that was in good condition.

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47 11. Does your agency have specific reasons for selecting a particular membrane system Yes: 22 agencies No: 9 agencies 12. Please identify the reasons for selecting a particular membrane system. Percentage Response a.Cost b. Speed of installation c. Staged construction options d. Surface preparation e. Track record of previous installations f. Desired service life g. Availability h. Coordination requirements i. Product support j. Other If other, please describe briefly. Other reasons given were as follows: Waterproofing membranes that were observed to have a significantly reduced service life were eliminated from use. Waterproofing membranes that were observed to have a significantly longer service life were permitted for use on more projects. Ease of instal- lation and speed of installation were also criteria given our short construction season, but were of less concern than service life and proven installations. They provide extended rideability for a deck that is in very bad shape. We have spray applied and sheet applied systems. The sprays applied are more expensive and tend to be better performing in difficult or high risk decks; i.e., with environmental concerns. Compatibility with asphalt temperatures.