Sourcefile info: C:\WJE Work\Element history.xlsx\Sheet1 Chart 1 I-195 Washington Bridge (700) Forensic Evaluation and Procedural Audit Related to PT Tie-Down Failures I-195 SB Washington Bridge over Seekonk River Providence, RI Draft Report February 29, 2024 WJE No. 2023.7858.0 Prepared For: Mr. John Preiss State Bridge Engineer Rhode Island Department of Transportation Two Capitol Hill Providence, Rhode Island, 02903 Prepared By: Wiss, Janney, Elstner Associates, Inc. 2941 Fairview Park Drive, Suite 300 Falls Church, Virginia 22042 703.641.4601 tel I-195 Washington Bridge (700) Forensic Evaluation and Procedural Audit Related to PT Tie-Down Failures I-195 SB Washington Bridge over Seekonk River Providence, RI Draft Report February 29, 2024 WJE No. 2023.7858.0 Prepared For: Mr. John Preiss State Bridge Engineer Rhode Island Department of Transportation Two Capitol Hill Providence, Rhode Island, 02903 Prepared By: Wiss, Janney, Elstner Associates, Inc. 2941 Fairview Park Drive, Suite 300 Falls Church, Virginia 22042 703.641.4601 tel Double-click or select Graphics button to insert pic Double-click or select Graphics button to insert pic Michael C. Brown, PhD, PE Associate Principal I-195 Washington Bridge (700) Forensic Evaluation and Procedural Audit Related to PT Tie-Down Failures Draft Report | WJE No. 2023.7858.0 | February 29, 2024 Contents Introduction 1 Purpose and Scope of Review 1 Background 1 Documentation Review 3 Original Design (1967) 3 Framing Plan and Cantilever Design 3 PT Tie-down Anchor Rods 1 Cantilever Post-Tensioning 5 Special Evaluations and First Rehabilitation 6 Lichtenstein Emergency Inspection Report, January 1992 6 1997-8 Rehabilitation 7 Whitlock, Dalrymple, and Poston Investigation, August 1996 and July 1997 7 Inspection Reports 8 Routine Inspection by AI Engineers, July 2007 9 Routine Inspection by TranSystems, August 2009 9 Routine Inspection by Michael Baker International, August 2011 9 Routine Inspection by AI Engineers, August 2013 9 Routine Inspection by AECOM, July 2015 10 Special Inspection by TranSystems, July 2016 10 Routine Inspection by Collins Engineers, July 2017 11 Special Inspection by Michael Baker, July 2018 11 Routine & Special Inspection by AECOM, July 2019 11 Special Inspection by AECOM, July 2020 12 Routine and Underwater Inspection by Jacobs, July 2021 12 Special Inspection by TranSystems, July 2022 12 Routine Inspection by AECOM, July 2023 12 Special Inspection by AECOM, December 2023 12 Element Condition State Progression 12 February 29, 2024 Page Wiss, Janney, Elstner Associates, Inc. 2941 Fairview Park Drive, Suite 300 Falls Church, Virginia 22042 703.641.4601 tel www.wje.com Atlanta | Austin | Boston | Chicago | Cleveland | Dallas | Denver | Detroit | Doylestown | Honolulu | Houston | Indianapolis London | Los Angeles | Milwaukee | Minneapolis | New Haven | Northbrook (HQ) | New York | Philadelphia | Pittsburgh Portland | Princeton | Raleigh | San Antonio | San Diego | San Francisco | Seattle | South Florida | Washington, DC Introduction Wiss, Janney, Elstner Associates, Inc. (WJE) is pleased to provide the Rhode Island Department of Transportation (RIDOT) with this review of events preceding failure of post-tensioned anchor rods at Pier 7 of the southbound I-195 Washington Bridge north structure (700). WJE has been engaged to perform a review of the events leading to the discovery and to evaluate the cause of the rod failures. Purpose and Scope of Review WJE was tasked with performing a review of records and history leading to the failure and to provide its assessment of: what events and conditions led to the failure of the rods whether the agency’s decision to close the bridge to traffic was reasonable whether conditions leading to the failure could have or should have been foreseen whether conditions discovered after the failure revealing more serious condition of cantilever beams should have been foreseen what actions or policy recommendations may be recommended to prevent similar types of events from occurring in the future WJE’s efforts consisted of two major thrusts: Forensic analysis of the failed PT tie-down rods Detailed review of agency records to understand the design, construction, maintenance, inspection, repair, and rehabilitation history of the structure in general, with particular focus on the post-tensioned concrete cantilever beams and associated support corbels/pedestals and tie-down rods at Piers 6 and 7. While WJE maintained a general awareness of the continuing investigation and design of mitigation repairs concurrently underway, RIDOT made a conscious decision to firewall WJE from day-to-day meetings and discussions so as not to have those discussions bias WJE’s review. For this review, WJE made requests for information through direct interaction with Mr. John Preiss, State Bridge Engineer, for RIDOT. Background The subject bridge is an 18-span structure comprised of prestressed/post-tensioned concrete multi-girder approach spans (6 west / 11 east) and a steel multi-girder main span (Span 7). There is also a curved three-span prestressed concrete box girder ramp to Gano street exiting to the north at the west end. The Structure Inventory & Appraisal (SI&A) information in the July 2023 inspection report indicates the bridge is 1,903.87 ft long with a maximum span length (Span 7) of 130.60 ft. The structure was designed to be nominally 75 ft wide out-to-out and 68 ft curb-to-curb. Total deck area is reported to be 152,958.0 square feet. The bridge was closed to traffic on December 11, 2023 after construction workers reported observation of a full fracture of one of the post-tensioned (PT) rods used to tie down the end spans of east and west approaches to the substructure. WJE personnel Michael Brown and John Cocca visited the bridge on December 16, 2023. During the site visit we observed the fractured bars in situ and the configuration and condition of the cantilever beams and structural walls at Piers 6 and 7 that the post-tensioned (PT) rods were designed to connect. During the visit, WJE observed the fractured rods at two of four corners of Span 7, at Cantilever A and Cantilever F at Pier 7. At the time, a third rod, Cantilever A at Pier 6, was suspected of also being fractured due to observed movement of the cantilever/rod, but a fracture could not be visibly confirmed. A report noted bouncing of cantilevers and gaps at bearings of adjacent girder lines at the Pier 6 and Pier 7 connections. 1 VHB Visit Findings 12-11-23 (Additional Info) (Reduced).pdf 1 Photos of the fractured bars taken by WJE on December 16, 2023 are shown in Figures 1 and 2 . The bars were corroded on the exterior perimeter and the cross-section was reduced/tapered in the regions around the fractures. Figure 1 . Pier 7 Cantilever A fractured tie-down rod Figure 2 . Pier 7 Cantilever F fractured tie-down rod Documentation Review To review the structure’s composition and history predating the reported failure, WJE requested copies of original design documents, inspection reports, special study reports, rehabilitation project plans, specifications, and contract documents, as well as construction inspection daily reports and summaries. Original Design (1967) WJE reviewed original design plans, applicable (non-project-specific) standards and specifications, structural calculations, and shop drawings. The original design for the bridge was completed in January 1967 by Charles A. Maguire & Associates Engineers of Providence, RI. The design referenced the then current American Association of State Highway Officials (AASHO) specifications, including the Standard Specifications for Highway Bridges, 9th edition 2 Standard Specifications for Highway Bridges , Ninth Edition, American Association of State Highway Officials, Washington, D.C. 20004, 1965 2 , and the 1965 edition of Rhode Island Standard Specification for Road and Bridge Construction 3 Standard Specifications for Road and Bridge Construction , State of Rhode Island and Providence Plantations Department of Public Works, Division of Roads and Bridges, State Office Building, Providence Rhode Island, Revision of 1965 3 . Framing Plan and Cantilever Design The following summarizes aspects of the original design relevant to the post-tensioned cantilevers, prestressed drop-in beams, Pier 6 & 7 support corbels and post-tensioned tie-down rods. The approach structures in Spans 1 through 6 and 8 through 13 comprise post-tensioned concrete balanced cantilever beams on concrete piers that support prestressed concrete drop-in girders between them ( Figure 3 ). Unbalanced post-tensioned concrete cantilever beams at end spans at Abutment 1 (C-1 through C-6) and Piers 6 and 7 (C37 through C42 and C-43 through C-48, respectively) support drop-in beams at one end and are tied down at the abutment or pier wall at the other to provide counter force ( Figure 4 ). The unbalanced cantilevers were designated “Type D” in the drawings and the length of cantilever at the tie down end was longer than the drop-in end ( Figure 5 ). These end cantilever segments are tied down with high-strength PT rods to reinforced concrete corbels on the face of Abutment 1 to balance Span 1 drop-in beams and to structural walls of Piers 6 and 7 to either side of the steel main span, Span 7, to counterbalance the loads of the drop-in beams in Spans 6 and 8. February 29, 2024 Page Figure 3 . Full Framing Plan with concrete beam designations (Sheet 70, Framing Plan) of original plans (1967). Fracture near bottom of tie-down rod. Fracture at top of tie-down rod. Reported bouncing of tie-down rod. Figure 4 . Framing Plan and Elevation of Spans 6 through 8, southbound I-195 Washington Bridge North (700) I-195 Washington Bridge (700) Forensic Evaluation and Procedural Audit Related to PT Tie-Down Failures Draft Report | WJE No. 2023.7858.0 | February 29, 2024 Page Figure 5 . Type D Cantilever Beam at Pier 6 & 7 (Sheet 74, Cantilevers Sheet 1) of original plans (1967). PT Tie-down Anchor Rods There are six concrete girder lines (A-F), each with twin tie-down rods connected to an anchor plate at the top that straddles the cantilever beam ( Figure 6 ). The tie-down rods are embedded in the diaphragms at ends of the cantilever beams and extend down into the corbels, making them thus not visible for inspection. However, at the four outward corners at girder lines A and F of Piers 6 and 7, the outboard tie-down rods lie to the exterior of the cantilever beam ends, where there are no diaphragms, and are exposed from the top of the beam seat to the bottom of the concrete deck. Original design drawings required the prestressing rods to be 1 3/8” diameter threaded high strength pre-stressing rod (Figures 7 and 8 ). Figure 6 . Section depicting PT anchor plates and tie-down rods at end span cantilever supports (Sheet 143, Detail Sheet 8) of original plans (1967). Figure 7 . Section depicting steel and concrete beam bearing and PT anchor plates and tie-down details for Pier 7 (Sheet 139, Detail Sheet 4 ) of original plans (1967). Figure 8 . Section depicting steel and concrete beam bearing and PT anchor plates and tie-down details for Pier 6 (Sheet 143, Detail Sheet 8) of original plans (1967). Per Sheet 79, Cantilever Beam Anchorage of the original plans (1967), “The high strength steel to be used for anchor plates, hold down plates and plate washers shown on sheets listed below shall conform to ASTM designation A107-61T Grade 1040 for bar sizes and shall be from rolled billets conforming to the same designation as well as the requirements of ASTM designation A-6 for plate sizes with the following physical requirements: Min Ultimate Strength = 91,000 p.s.i. Min Yield Point = 50,000 p.s.i.” Structural design calculations for tie-down anchor plates reflect these yield and ultimate strengths. No standard specification was specifically cited in the plans for the high-strength prestressing/post-tensioning rod and original project specifications were not provided. However, the 1965 Rhode Island Standard Specification for Road and Bridge Construction contains provision for high-tensile-strength alloy bars, which would have been applicable ( Figure 9 ). Figure 9 . M.05.03 Prestressing Reinforcement Steel, Standard Specifications for Road and Bridge Construction, Revision of 1965, p. 319. The design was performed according to allowable stress design (ASD) procedures. The applicable AASHO specifications limited stress at design load to the lesser 0.60 f’s (min ultimate strength) or 0.80 fsy (nominal yield stress @ 1.0% extension). Per structural drawings (Sheets 139 and 140), PT tie-down rods were each to be post-tensioned to 120,000 lbf. Structural design calculations indicate PT rods were assumed to be centered 1 inch from the outside face of each cantilever web face and that expected design loads on the rods was Pmax = 142.6 kips, or P working = 140kips. 4 1967 070001 Cantilever Stems and Connections - Design Calcs.pdf 4 Based on a calculated cross-sectional area of 1.485 in2 for a 1 3/8-inch diameter bar, the calculated effective working stress was 94.3 ksi. Note this would represent 0.65 f’s and 0.725 fsy if the high strength rod used matched the RIDOT specification. From Stressteel Corp. shop drawings, a separate calculation of bar stress accounting for creep, shrinkage and relaxation losses indicated a target applied post-tension stress of 92.63 ksi. Unfortunately, records WJE reviewed did not specifically identify the steel used for the rods. However, tests of the materials from the two failed rods indicated ultimate strengths of 158.9 and 165.5 ksi, such that design stress was ≤ 0.60fsu (average stress at ultimate load) based on 140 kip working load. Cantilever Post-Tensioning The Type D cantilever beams were internally post-tensioned with 4 cables that draped and spanned over the pier stem support from the beam ends (Cables 1, 2 & 3 ) or between locations along the bottom flange (Cables 4 & 5) as shown in Figures 10 and 11 . Type D cantilever beams comprised 5,000 psi concrete post-tensioned with cables composed of 12 -1/2” diameter strands. Tendons were grouted after post-tensioning. Shop drawings indicate the grout used was as shown in Figure 11 . The stated range of water (5 to 6 gallons per bag of cement) would be equivalent to a water-to-cement ratio (w/c) range of 0.44 to 0.53 for Mixture A. Figure 10 . Post-tensioning layout for Type D Cantilever Beams (Sheet 78, Cantilevers Sheet-5) of original plans (1967). Figure 11 . Post-tension anchorage details in cantilever beams (Sheet 78, Cantilevers Sheet 5) of original plans (1967). Figure 11 . Grout mix design excerpt from shop drawing. 5 1967 070001 Prestress Shop Drawings and Calcs.pdf 5 Special Evaluations and First Rehabilitation Lichtenstein Emergency Inspection Report, January 1992 Lichtenstein completed an emergency inspection, testing, and evaluation of the cantilever beams and ship-lap details of the bridge and reported, “the condition of the shiplap details (corbels) in the precast post-tensioned concrete cantilever beams are deteriorating. The damage found is localized to the area below the roadway joints and is more severe on the lower shiplap (corbel), which supports the drop-in spans. There is a precast U-shaped buildout on the end of each corbel which forms a stressing pocket for the two post-tensioning tendons which terminate in the corbel at a heavy steel bearing plate cast into the beams…The grout in the stressing pocket and the precast shoulders of the cantilever beams are all showing signs of distress.” The post-tensioning tendons were identified as comprised of Freyssinet 270 ksi 7-wire strand, with dead ends of the wires protruding beyond the standard anchorages. Concern was expressed about stress corrosion resulting from moisture and salt exposure. The report went on to relate the results of chloride testing and radiography. Chlorides were reported to be high (~11.5 pcy) but results were unusually uniform and therefore suspect. Radiography was used to look for broken strands, which were not identified; however, shadows in the images suggested the presence of voids in the grouted tendons. From calculations performed to evaluate stress in the cantilever beams and corbels, the authors conclude that, “Stress in the prestressing strands after calculated losses is estimated at 54% of the ultimate strength of the strands which is below the stress allowed by AASHTO.” They later stated, “Due to the structural redundance of the wires, strands and beams and the fact that we calculated strand stresses of approximately 54% of ultimate after losses, there is reason to believe that a failure of some wires would not result in catastrophic collapse, but if one corbel were found with major distress indicative of a shear failure, the failure of adjacent corbels might occur rapidly.” The authors also noted, “The secondary area of concern in the post-tensioned cantilever beams is in the beam webs where cracks through have been found that follow the tendon profile.” They surmised, “there are two conceivable causes for this type of cracking: the cracks may have formed during construction during initial tensioning of the strands due to an overstress of the concrete or the cracks could be caused by expansive forces created by corrosion of the tendon ducts. Through a series of calculations, the authors concluded that the calculated principal stresses, at the level of the tendons, would have caused cracking if the concrete strength at the time of post-tensioning were below 4000 psi or even perhaps if slightly above, concluding, “Calculations indicate that the diagonal cracks, which follow the tendon profile in all likelihood were formed during initial tensioning of the tendons” and, “these cracks have not grown and will probably not grow in the future.” 1997-8 Rehabilitation After identification of the issues with corbels and PT strands, a rehabilitation project was designed in 1996-97. The plans were developed by Vanasse Hangen Brustlin, Inc. (VHB) of Providence, RI. The project included series of repairs to the corbels of the cantilever beams. Whitlock, Dalrymple, and Poston Investigation, August 1996 and July 1997 In association with the rehabilitation project, greater deterioration was discovered in July 1996 in the corbel support of the cantilever-drop-in beam connections than previously anticipated. 6 Time Analysis: Conception Through Construction to Date, Washington Bridge No. 700, R.I. Contract No. 9603 by David F. Arnold, Arnold Engineering Company, Inc., September 22, 1997, as found in file “1997-09-10 Correspondence from Sen. Roney to Director Anker.pdf” 6 AECOM Final Technical Evaluation Report Inspection Reports Access to inspection reports was provided via AASHTOWare BrM and SharePoint. WJE received documentation of the biennial routine inspections, underwater inspections conducted on a four-year cycle, and a series of special inspections, as listed in Table 1 . Special inspections were performed during years alternate to routine inspections from 2016 forward as the bridge was placed on a 12-month inspection cycle primarily due to progressing deterioration. Some special inspections were requested to investigate specific issues. Table 1 . Washington Bridge 700 inspection reports reviewed Report Date Inspection Firm Inspection Type General Condition Rating ( yyyy-mm-dd) Deck Superstructure Substructure 2007-07-01 AI Engineers Routine 6 4 5 2009-06-29 Specialty Diving Services Underwater - - - 2009-08-07 TranSystems Routine 6 4 5 2011-08-03 Michael Baker Routine 6 4 5 2013-08-02 AI Engineers Routine 6 4 4 2013-08-07 Collins Engineers Underwater - - - 2015-07-28 AECOM Routine 6 4 4 2016-07-15 TranSystems Special 6 4 4 2017-07-24 Collins Engineers Routine 6 4 4 2017-07-24 Collins Engineers Underwater - - - 2017-10-27 AECOM Special - - - 2018-07-24 Michael Baker Special - 4 4 2019-07-24 AECOM Routine and Special 6 4 4 2020-07-22 AECOM Special 6 4 6 2021-07-23 Jacobs Routine and Underwater 6 4 6 2022-07-22 TranSystems Special 6 4 6 2023-07-21 AECOM Routine 6 4 6 2023-12-17 AECOM Special 6 4 6 The progression of inspection reports demonstrates the transition from solely NBI-based inspections to incorporate element-level inspection, first within Pontis and then in AASHTOWare BrM. For example, the 2007 inspection report lists the addition of 30 CoRe elements and associated quantities into Pontis for the bridge. The August 2011 routine inspection by Michael Baker made significant changes to element quantities, such as removing railings and adding to parapets and adding concrete diaphragms. The July 2015 inspection by AECOM reflected the addition of Defects to elements in accordance with the transition from CoRe elements to NBE/BME elements. Over the period from 2007 to 2023, six different engineering firms conducted routine and special inspections of the bridge (plus underwater inspections), with some firms completing multiple inspections, but per RIDOT policy, consecutive routine inspections were not conducted by the same firm. From the review, the following are highlights from the inspection reports as pertain to cantilever beams, drop-in beams, corbels, and tie-down rods, with emphasis on Piers 6 & 7 cantilevers at Span 7. Routine Inspection by AI Engineers, July 2007 The superstructure general condition rating (GCR), NBI item 59, was downgraded from 5 to 4 based on prestressed girder spalls with exposed strands and reinforcing bars at random locations. The deck GCR, NBI Item 58, was upgraded from 5 to 6 based on observed satisfactory condition of underside of deck. Added types, quantities, and condition states for 30 elements. Cracks were noted, 0.005-inch width, on Span 6 cantilever elevation that seem to align with PT ducts. Routine Inspection by TranSystems, August 2009 Condition of lower areas associated with Pier walls 6 & 7 are noted as unconfirmed due to inaccessibility beneath catwalks. Asphaltic plug joints in all mainline spans except span 5 in good condition…evidence of joint leakage was noted at random locations below the joints. Element 109 Prestressed Concrete Open Girders (these are the post-tensioned cantilever beams) - 11 entries reflect defects in cantilever beams of spans 6 and 8 at Piers 6 and 7, respectively. Field notes page containing Span 7 and tied down cantilevers of spans 6 & 8 have very few notes on the cantilevers and focus mainly on Span 7 steel span. Routine Inspection by Michael Baker International, August 2011 Asphaltic plug joints in spans 3, 7, 8, 12 and at pier 14 have adhesion separation up to 25% of the length of the joint x up to ½” wide in the travelway and up to 1½” wide in the right shoulder…Evidence of joint leakage was noted at random locations below the joints and isolated areas of joint filler material were hanging down. Cantilever ends at corbels typically have cracks with isolated efflorescence and rust, hollow areas and spalls with exposed anchorage plates (plates typically have laminated rust with negligible section loss). Pier 6 & 7 walls have hollow areas and spalls, and above the deck have hollow areas throughout entire face up to 4’ x 3’ with cracks with isolated efflorescence and rust. Piers 6 & 7 have high reinforced walls on all sides with a catwalk. There are scattered hairline cracks at the tops of these walls and insides were inspected from the catwalk and have random hairline cracks and the diaphragm supports at the span 7 sides typically have hollow areas and spalls with exposed rebar. Cracking, efflorescence, and spalls clearly related to the embedded PT tendon profiles at Span 6, Girder E and Span 8, Girder B. Corbels inside of Pier 7 at catwalk with evidence of spalls and cracks. Corroded rocker bearings A Span 7 at pier 6 and pier 7, evidencing significant joint leakage above. Routine Inspection by AI Engineers, August 2013 Substructure GCR, NBI Item 60, changed from 5 (Fair) to 4 (Poor). Inspection included critical findings regarding Span 13 Girder F and Span 6 Girder F webs and Span 14 Girders A & F loss of section and bearing. Cantilever ends at corbels typically exhibit cracks with isolated efflorescence and rust, hollow areas and spalls with exposed anchorage plates (plates typically have laminated rust with negligible section loss)… Also, there is a spall up to 18” x 12” x 6” deep exposing the anchor plate and undermining the bearing pad at east corbel to girder B in span 6. Pier 6 & 7…interior walls and support columns exhibit areas of heavy spalls with corroded rebars on walls up to 3’ x 2’ x 5” deep and columns up to full height x full width (2.5’) x 6” deep. Field notes show cracking on web faces of cantilevers at Pier 6 that appear to align with PT ducts. Field notes for Span 7 omit cantilever portions of Spans 6 and 8 within the Pier 6 and Pier 7 walls. Routine Inspection by AECOM, July 2015 The post-tensioned concrete cantilever girders in Spans #1 through #14 were reported to be in overall satisfactory to fair condition. Element 109 - Post Tensioned Cantilever I-Girders condition states (CS) quantities were adjusted to reflect the current conditions. Isolated severe spalling with reduced bearing area and fully exposed/corroded stirrups to drop-in girder ends and cantilever girder ends. Defects table lists web diagonal cracks noted in many cases to follow the path of post-tension cables emanating at anchorage blocks. Numerous girders (16%) exhibit hairline diagonal web cracks that follow the path of post tension cables. These cracks generally start at the free end of the cantilever near the post-tension anchorage blocks and can extend up to 10’+ to the top of the webs. Isolated girders have hollow areas and shallow spalling along these cracks or cracked and hollow grout pocket patches. Post-tension anchorage blocks on the underside of the bottom flanges are typically cracked with efflorescence and rust staining. Numerous blocks are hollow or spalled with isolated exposed steel anchorage plates. In Span #7, the ends of the cantilever girders exhibit typical spalling up to full height x up to 7” deep over the bearings with multiple fully exposed, debonded, and broken stirrups. The concrete cantilever girder pedestals on the interior walls of Piers 6 east wall and 7 west wall (behind the steel girder seats) exhibit typical spalling up to full height x full length x up to 7” deep and undermine the cantilever girders. Special Inspection by TranSystems, July 2016 This special inspection was for the superstructure and substructure only; to inspect the deteriorated condition of elements. For Element 109, prestressed girders/corbels typically exhibit spalls with exposed rebar, section loss on exposed rebars, hollow areas, concrete patches, efflorescence, rust stains and leakage stains. There are scattered cracks (some structural shear cracks). In Span 7 at interior of Piers 6 and 7, the cantilever girder thin bearing pads are undermined up to 7" deep due to pedestal spalls and exhibit moderate to heavy crushing/bulging. The post-tensioned concrete drop-in corbels in Spans #1 through #14 exhibit scattered hairline cracking open up to 0.012" wide; with few locations showing wider cracks, hollow areas, spalls with exposed reinforcing plates and efflorescence/rust stains at deteriorated locations. There are scattered locations with heavy accumulation of pigeon debris which limits inspection access, and isolated locations with evidence of leakage. The corbels exhibit typical honeycombing of lower faces up to 2" deep, with scattered hairline cracking, hollow areas, efflorescence and rust staining. In multiple locations the cracks and hollow areas extend to the corbel undersides with spalling. Isolated underside have heavier deterioration with multiple cracks, leakage stains, hollow areas and spalls up to 2" deep with exposed reinforcement along corbel edges…The lower end faces of the corbels exhibit typical intermittent hollow areas and spalls at the corners; some with exposed corroded reinforcing plate and up to 3.5" deep; some elastomeric bearings are undermined due to spalls. The upper end faces of the corbels beyond the drop-in beam bearings exhibit typical scattered spalls up to 2" deep with rust staining and exposed/ corroded post-tension reinforcing plates. Routine Inspection by Collins Engineers, July 2017 In Span #7 at the interior of Piers #6 and #7, the ends of the cantilever girders exhibit spalling up to full height x up to 8” deep over the bearings with multiple fully exposed, debonded, and broken rebars. The cantilever support pedestals on the interior walls of Piers #6 east wall and Pier# 7 west wall (behind the steel girder seats) exhibit random hairline cracks, isolated hollow areas and spalls without and with exposed rebar which undermine the masonry plates. The spalling on the cantilever support pedestals has exposed and debonded rebar, section loss on exposed rebar, and isolated broken rebar. The cantilever support pedestals exhibit uneven bearing pedestals and missing/deteriorated grout pads resulting in gaps under the masonry plates and loss of bearing area at random bearings. There are several defects which have been repaired or in the process of being repaired during the inspection. The east pier wall at Pier #6 and the west pier wall at Pier #7 exhibit hollow areas and spalls. The cantilever support pedestals on the interior walls of Pier #6 east wall and Pier #7 west wall exhibit hollow areas. The cantilever support pedestals exhibit uneven bearing pedestals and missing/deteriorated grout pads resulting in gaps under the masonry plates. The east pier wall at Pier #6 and the west pier wall at Pier #7 exhibit spalls with exposed and debonded rebar with section loss. The cantilever support pedestals on the interior walls of Piers #6 east wall and Pier #7 west wall exhibit spalls with exposed rebar. The spalling on the cantilever support pedestals have exposed and debonded rebar, section loss on exposed rebar, and isolated broken stirrups. Special Inspection by Michael Baker, July 2018 The purpose of this special inspection is to monitor the condition of the superstructure and substructure due to deteriorated condition per BI-011 on file dated 10/26/15. Note, rehabilitation construction activities are on-going and were occurring at the time of this special inspection. Based on the results of this special inspection, the bridge overall is in poor condition. Substructure (Rating = 4) – The substructure has hollow areas and spalls at the cantilever pedestals. The pier walls that support span 7 have cracking. The cantilever support pedestals on the interior walls of Piers 6 east wall and Pier 7 west wall (behind the steel girder seats) have scattered up to 16” long x 3/16” wide vertical and horizontal cracks, and up to 3’ high x full pedestal width concrete patches. Amended quantities of defects in Elements 109 (incl. new spalls, exposed reinforcing bar and delaminations in Span 7) and 210 (some due to ongoing repairs). Several long diagonal cracks were noted in webs of cantilever beams, some potentially aligned with PT ducts. Routine & Special Inspection by AECOM, July 2019 "Rehabilitation construction is on-going and there are multiple defects that have been repaired or are in the process of being repaired…There is scaffolding in place throughout the structure allowing access to the drop -in girder ends and corbels.” For element 109, the corbels exhibit typical cracked, hollow and spalled areas with exposed post tensioned anchor plates on the drop-in span sides throughout. The other faces and undersides exhibit isolated cracks, hollow areas and minor spalls. The cantilever girders exhibit typical hairline diagonal cracks along the post-tensioned cable lines, some sealed and unsealed, isolated vertical cracks and hollow area over the pier columns and typical hollow/spalled post-tensioned anchor blocks on the undersides. Other remaining areas exhibit random minor cracked, hollow and spalled areas. The cantilever ends in Span #7 at Pier #6 and Pier #7 (accessed via the catwalks on the interior walls of the piers) exhibit typical hollow areas/spalls up to full height with fully exposed and debonded stirrups and reduced bearing areas. Special Inspection by AECOM, July 2020 “The special inspection includes the superstructure and substructure… There is scaffolding in place throughout the structure (from previous bridge rehabilitation construction) allowing access to the drop-in girder ends and corbels. There is typical construction debris scattered through the scaffolding. The condition rating for Item 60 - Substructure has been increased from (4 - Poor) to (6 - Satisfactory) based on the repairs which have been made throughout the bridge substructure elements. The cantilever ends in Span #7 at Pier #6 and Pier #7 (accessed via the catwalks on the interior walls of the piers) exhibit typical hollow areas/spalls up to full height with fully exposed and debonded stirrups and reduced bearing areas. Element 109 Defect Table for spans 6 - 8, lists several cantilever beams that exhibit diagonal cracks aligned with PT anchorage blocks. Routine and Underwater Inspection by Jacobs, July 2021 This inspection reports very few changes in conditions or defects overall and none to elements 109 and 210. The report contains identical typographical errors to those found in the preceding special inspection report by AECOM. There were 4ft CS3 for scour undermining (element 220) from the 2021 UW report. Special Inspection by TranSystems, July 2022 For Element 109, there were changes to defects 1080 (4 ft improved from CS3 to CS2) and 1090 (5 ft improved from CS3 to CS2). The only other changes referred to graffiti and nesting birds. Routine Inspection by AECOM, July 2023 For Element 109, some improvements were reflected, with quantities moving from CS3 & CS4 to CS2. Special Inspection by AECOM, December 2023 The inspection, necessitated by a critical finding during construction, noted some deterioration of Element 109 from CS1 to CS2 & CS3. Element Condition State Progression The subject post-tensioned concrete cantilever beams for this structure are catalogued as Element 109, Prestressed Concrete Open Girder in Pontis/BrM. The condition states for each inspection are tabulated in Table 2 . Note that a significant change occurred between 2013 and 2015 reflecting a dramatic increase in the percentage of the element rated in CS1. Since no rehabilitation occurred during this period, the change in condition is likely attributable to the transition from Core Elements to NBEs and BMEs, including the incorporation of quantified Defects under the Elements, but does not reflect a commensurate improvement in condition. Rather, it is as if one were measuring with a different scale. Figure 13 shows the proportions in CS1 through CS4 after 2013. The jump in CS4 quantities in 2016 reflects discovery of additional defects during the special inspection. Conversely, the improvement in condition between October 2017 and July 2018 would be associated with the rehabilitation project underway at that time. However, little significant improvement in condition occurred after that time and some previously good portions of the girders continued to deteriorate. Table 2 . Element 109 Prestressed Concrete Open Girder – Condition State History Date Total CS1 CS2 CS3 CS4 July 2007 14543 FT 40.0% 5817 30.0% 4363 20.0% 2909 10.0% 1454 June 2009 14543 FT 40.0% 5817 30.0% 4363 20.0% 2909 10.0% 1454 August 2009 14543 FT 40.0% 5817 30.0% 4363 20.0% 2909 10.0% 1454 August 2011 14543 FT 53.2% 7739 30.0% 4363 15.0% 2181 1.8% 260 August 2013 14543 FT 53.2% 7737 30.0% 4363 15.0% 2181 1.8% 262 August 2013 14543 FT 53.2% 7737 30.0% 4363 15.0% 2181 1.8% 262 July 2015 14543 FT 84.9% 12347 10.0% 1454 4.0% 576 1.1% 166 July 2016 14543 FT 80.6% 11724 4.3% 629 11.5% 1673 3.6% 517 July 2017 14543 FT 80.6% 11721 4.3% 632 11.5% 1673 3.6% 517 October 2017 14543 FT 80.6% 11721 4.3% 632 11.5% 1673 3.6% 517 July 2018 14543 FT 80.7% 11733 8.7% 1268 9.7% 1407 0.9% 135 July 2019 14543 FT 80.7% 11733 8.7% 1268 9.7% 1407 0.9% 135 July 2020 14543 FT 80.1% 11650 8.9% 1290 10.1% 1468 0.9% 135 July 2021 14543 FT 80.1% 11650 8.9% 1290 10.1% 1468 0.9% 135 July 2022 14543 FT 80.1% 11650 8.9% 1299 10.1% 1464 0.9% 130 July 2023 14543 FT 80.1% 11647 9.6% 1397 9.6% 1394 0.7% 105 December 2023 14543 FT 79.9% 11621 9.7% 1408 9.7% 1409 0.7% 105 January 2024 14543 FT 79.9% 11623 9.7% 1409 9.7% 1406 0.7% 105 Source: RIDOT AASHTOWare BrM Figure 13 . Element 109 Condition State History 2016 Rehabilitation In January 2015, AECOM issued a Final Technical Evaluation Report 7 Final Technical Evaluation Report - Washington Bridge North No. 700, Providence and East Providence, Rhode Island RI Contract No. 2014-EB-003, AECOM technical Services, Inc., January 2015. 7 for Washington, starting with a summary of a special inspection completed in 2014 and progressing to recommendations for a rehabilitation. In its summary of the 2014 special inspection, regarding the prestressed girders, AECOM noted: “Drop‐In Prestressed Beam Ends, Reinforced Concrete Diaphragms and Post‐Tensioned Cantilever Corbels exhibit prevalent cracked, hollow sounding and spalled concrete with multiple exposed stirrups, longitudinal reinforcement and prestressing strand ends below drop‐in span deck joints. Isolated spalls in these areas reduce drop‐in beam bearing area and/or undermine bearing pads throughout the bridge. Post‐Tensioned Cantilever Beams exhibit typical hairline web cracking running parallel to the post‐tensioned cables with prevalent spalling of concrete anchorage blocks exposing moderately to heavily corroded steel anchorage plates throughout. Isolated beams exhibit hairline vertical cracking and hollow concrete over bearing locations.” The proposed major repairs included: concrete beam end repairs, bearing repairs, deck repairs, beam end strengthening (FRP), pier cap strengthening (FRP), waterproofing membrane and asphalt wearing surface replacement, and joint repairs and elimination. Several parts of the structure were identified as requiring strengthening to increase the live load carrying capacity from HS‐20 to HL‐93 design loading, for which externally applied fiber reinforced polymer (FRP) was proposed to strengthen concrete beam and pier cap members. AECOM’s report stated, “Two joint elimination scenarios were evaluated and a scenario that eliminates 65% or 23 of the existing 35 deck joints is recommended as the preferred alternative. An approximate 6’ wide portion of deck will be removed and reconstructed at the 23 locations where joints will be eliminated. The remaining 12 joints will consist of strip seal joints (8 locations), asphaltic plug joints (2 locations) and pourable joint seals (2 locations). The impact that joint elimination has on the pier columns was investigated and all pier columns were found to be adequate.” Structural Modeling “AECOM modeled the portion of the structure from span 1 thru span 14…The models accounted for dead loads, live loads, braking force, temperature loads and site specific seismic loads. Geometry was based on the existing 1967 drawings.” “Except for span 7, spans 1 thru 14 consist of prestressed concrete drop‐in beam spans with variable depth post tensioned cantilever beams. This superstructure is supported by multi‐column pier bents founded on deep pile foundations. The beams support a reinforced concrete deck with a three inch asphalt wearing surface. The deck is modeled as shell elements and beams, diaphragms and columns are modeled as frame elements. Each drop‐in span is supported by a fixed and expansion bearing and this has been accounted for in the beam end releases defined in the model. The foundation pile cap and pile system were not modeled as part of the preliminary engineering effort and the restraint at the base of the reinforced concrete rectangular pier columns was taken as fully fixed for rotation and translation. It is anticipated that this full fixity can be more accurately modeled in final design by replacing full column fixity with a linear spring that reflects the stiffness provided by the pile layout.” In the summary of design loads for its analysis, AECOM noted the following was considered for temperature, “Per RIDOT 3.8, assume a Tmax of 100 degrees and a Tmin of 0 degrees. Assume an initial temperature of 50 degrees when evaluating temperature increase and an initial temperature of 70 degrees when evaluating temperature drop. So Trise = 100‐50 = 50 degrees; Tfall = 70 – 0 = 70 degrees (entered as ‐70 in CSI Bridge)” I-195 Washington Bridge (700) Forensic Evaluation and Procedural Audit Related to PT Tie-Down Failures Draft Report | WJE No. 2023.7858.0 | February 29, 2024 Page Figure 14. Joint elimination and replacement schemes, AECOM Final Technical Evaluation Report, January 2015. Top is as-constructed, and middle and bottom are two alternatives. Red indicates joint to be replaced (strip seal, asphalt plug joint, or pourable seal) and green indicates joint to be eliminated with deck closure pour. Figure 15. Link slab Location Plan from 2016 Rehabilitation plans, Sheet 44, RIDOT Contract 2016-CB-059, 2016. I-195 Washington Bridge (700) Forensic Evaluation and Procedural Audit Related to PT Tie-Down Failures Draft Report | WJE No. 2023.7858.0 | February 29, 2024 Page From the AECOM Technical Evaluation Report, “A link slab is proposed where joints are proposed for elimination. With Scenario 2, the link slab detail would be constructed at 23 locations. A link slab is comprised of a reinforced concrete deck with a length that extends approximately 5% to 7% of each adjacent span. A bond breaker is applied between the slab and the top flange of the beam to prevent composite action in this region.” Figure 16 reflects the detail issued for bid in the rehabilitation plans. To accommodate the restraint added by the partial depth closure pours, the joints at the ends of the newly adjoined units were to be reworked to accommodate greater anticipated movement. Figure 17 shows the proposed detail for a strip seal at a drop-in-cantilever corbel support, for example. Figure 16 . Link Slab Detail, Sheet 45, RIDOT Contract 2016-CB-059, 2016. Figure 17 . Strip Seal Joint Detail, Sheet 48, RIDOT Contract 2016-CB-059, 2016. Concerning the detailing of the joints to remain AECOM stated, “If deck continuity is constructed at 23 of the existing joints, 12 joints would remain on the bridge. The appropriate joint type at these 12 locations is based primarily on the amount of thermal movement that is anticipated. Table 7 – 1 [see Table 3 ] summarizes the total design movement that will need to be accommodated at each proposed joint location. The existing movement is provided for reference. As expected the proposed movement is greater than the existing due to the elimination of 65% of the deck joints.” Table 3 represents a selective excerpt from the cited Table 7 – 1, showing only the joints where it is proposed that joints remain and accommodate movement of the groups of adjacent spans connected by proposed joint closures. Note that the recommended scenario two to eliminate 23 of 35 joints results in closure of the three joints immediately west of Pier 6 east joint and closure of the 5 joints immediately east of Pier 7 west joint. These closures resulted in concentration of thermal movement over Table 3 . Total design movement to be accommodated at joint locations. Joint Location Total Movement Existing Total Movement Proposed Recommended Joint Type West Abutment East Joint 0.983 1.328 Strip Seal Pier 2 East Joint 0.822 1.536 Strip Seal Pier 4; East Joint 0.915 2.105 Strip Seal Pier 6; East Joint 1.588 3.226 Strip Seal Pier 7; West Joint 0.482 2.808 Strip Seal Pier 10; West Joint 0.954 2.684 Strip Seal Pier 13; West Joint 1.119 1.624 Strip Seal Pier 14 - TBD Strip Seal East Abutment < 0.25 <0.25 Pourable Joint Seal Gano St Ramp Span 1R <0.5 <0.5 Asphaltic Plug Gano St Ramp Span 2R <0.5 <0.5 Asphaltic Plug Source: Excerpt from Table 7 -1, AECOM Final Technical Evaluation Report, 2015 Table 4. <Insert Table Title> Source: <Insert Source here> Discussion: Inspection - Designed and built in era before the NBIS; element-level inspection evolved during the lifespan of the structure Inspection - There is no standard CoRe/NBE/BME element to represent the tie-down rods, so there is nothing to promote direct scrutiny of those components. Inspection – no “Owner’s Manual” to call attention to complex components (e.g., tie-down rods) Inspection – though complex, the tie-downs do not technically represent fracture critical /non-redundant steel tension members because there is redundancy (two rods per cantilever, 6 cantilevers per span) Inspection – most tie-down rods were encapsulated in concrete diaphragms and therefore not inspectable; the tie-down rods at the four corners of Span 7 were the exception Inspection – there appeared to be a general failure to recognize the significance of the tie-down rods; 6 firms Inspection – though there was considerable attention given to deterioration of the corbels and “loss of bearing”, little focus given to the rods, since most normal bearings function in compression (supporting downward gravity loads), not tension (resisting uplift of an unbalanced cantilever) Inspection – the unbalanced ends of Pier 6 and Pier 7 cantilevers at Span 7 were located inside the enclosed areas of Piers 6 and 7 such that access was limited to that enabled by catwalks (unless extraordinary measures were undertaken). The elevation of catwalks was such that base of tie rods at support corbels was above an inspector’s eye level Inspection – the two tie-down rods along the north face of beam line A at Pier 6 & 7 could be observed from the access hatch and ladder used to reach the catwalk inside the pier enclosures. However, without conscious effort to focus on the rods while descending the ladder , they could be easily overlooked. Evaluation - by Lichtenstein concluded that cracking along tendon profiles likely occurred at original construction and were not growing. Probing of the tendons should have been recommended but was not Inspection – reported growing length of cracks along tendons in cantilever beams, even after regrouting in 1998, but the growth was never called into question. Rehabilitation design - AECOM performed detailed girder line analysis and load rating to assess the implications of proposed joint elimination on the cantilevers themselves and moment induced in the pier stems. Rehabilitation design – Assessment of joint elimination on the Pier 6 & 7 walls was deemed unnecessary as they were found to be adequate in the 2012 load rating by MBI; no attention was given to the load on the tie-down rods. Rehabilitation design – AECOM report stated that thermal loading was considered. Their report tabulated increases in joint displacement in joints to remain at Span 7 after elimination of 3 joints to the west and 5 joints to the east. Although these increased movements were reported, no consideration seems to have been given to the moment and shear being introduced into the tie-down rods at the Pier 6 & 7 unbalanced cantilever supports. Rehabilitation construction – the 1996-8 rehabilitation encountered significantly greater deterioration in cantilevers, corbels and drop-in beam ends than previously thought, including voids in tendons and delaminations in the webs of cantilevers. Voids detected by impact echo and confirmed by drilling were grouted in cantilevers C37-C48 in Span 7 at Piers 6 & 7. Rehabilitation construction – the 2016 rehabilitation seemed to be plagued with poor coordination and very little emphasis on progressing the work. There were instances where back-to-back annual inspections showed very little change in element condition states that would reflect the benefit of ongoing repairs. Rehabilitation construction – inspection photos showed persistent incomplete patch repairs with poor preparation and opened areas remaining exposed for extended periods. “Prepared” patches contained corroded reinforcement and severed prestressing strands that were not cleaned or primed, nor supplemented with supplemental prestressing or splices. Many areas were not appropriately squared off or chipped to required depths below reinforcement. Rehabilitation construction - Although repairs were heavily concentrated at the east end of the bridge, the distribution and progress of patch repairs seemed very haphazard. Inspection reports document accumulation of construction debris and eventually bird feces on the scaffolding and falsework that remained in place for years. Rehabilitation construction – the 2016 repair plans called for FRP strengthening of cantilever beam corbels and drop-in beam ends; inspection photos do not reflect that any significant FRP wraps were ever installed. The bridge superstructure general condition rating remained 4 – Poor for more than a decade while known defects continued to grow and multiply. Many maintenance recommendations were repeated over multiple inspection cycles without being addressed.