TPF-5(188), Evaluation of Fiber Reinforced Composite Dowel Bars and Stainless Steel Dowel Bars

Transcription

1 TPF-5(188), Evaluation of Fiber Reinforced Composite Dowel Bars and Stainless Steel Dowel Bars Research Review Session October 13, 2011

2 TPF-5(188) Project Team Technical Panel Roger Green, Ohio DOT (Chairman) Mark Gawedzinski, Illinois DOT Andy Gisi, Kansas DOT Barry Paye, Wisconsin DOT Max Porter, Iowa State University Paul Virmani, FHWA TFHRC Consultants Roger Larson and Kurt Smith, APTech

3 Project Background 1996 FHWA Test and Evaluation Project 30 (TE-30) 1998 ASCE HITEC Evaluation Plan 2002 FHWA Alternative Dowel Bar Report 2003 HITEC Evaluation Resumed (APTech) 2005 HITEC Draft Interim Report 2006 FHWA Updated TE-30 Technical Summary 2008 TPF-5(188) Initiated

4 TPF-5(188) Project Tasks and Schedule Work Task Start End 1. Revise Draft Interim Report 10/17/08 5/1/09 2. Conduct Initial Web Conf 2/25/09 2/25/09 3. Execute Revised Eval Plan 5/1/09 7/1/11 4. Prepare Draft Final Report 1/1/11 6/14/11 5. Host Panel Meeting 6/20/11 6/20/11 6. Prepare Final Report 7/1/11 10/17/11 7. Provide Qtrly Progress Rpts -Each calendar qtr- 8. Conduct Close-out Mtg 10/13/11 10/13/11

5 TPF-5(188) Evaluation Approach Revised Evaluation Plan (April 2009) No laboratory testing Cores not full length specimens Field Testing of Alternative Dowel Bars 2009, 2010, and 2011 (Only OH & WI) FWD testing at FRP, SS, and control joints Chloride concentrations at top of dowel (ASTM C 1152 Acid Soluble)

6 TPF-5(188) Evaluation Approach (cont d) Coring 6 in diameter cores FWD testing done before coring Cores: outer dowel, 6 rd dowel, 8 th dowel Photographs, visual examination Chloride level at top of dowel in core Desirable versus minimum testing levels Profile evaluation to get IRI (and faulting?) Field evaluation of year old epoxycoated dowel projects

7 Chloride Testing (ASTM C 1152) Acid Soluble Residue

8 Ohio 2 (US 50, Athens) (constructed ) 71 Nominal Design: 10-in JRCP 21-ft Joint Spacing 4-in open-graded base 70 Columbus Athens 77 Dowel Bars: 1.5-in Epoxy 1.5-in FRP 1.5-in SS Tubes 1.5-in SS Clad 50 Ohio 2 U.S. 50, Athens

9 Current Findings Ohio 2 Very low LTE s on 1.5-in polyester resin FRP Intermediate LTE s on Type 304 solid stainless steel or mortar filled stainless steel tubes and Type 316 stainless steel clad dowels (EB-1998 constr.) Relatively good performance of epoxy-coated dowels major problem debonding of epoxy and rusting under coating but no loss of section

10 OH 2 EB (Approach Joint)

11 OH 2 EB (Leave Joint)

12 OH 2 EB (Epoxy-Coated)

13 OH 2 EB (Type 304 Stainless Steel Tubes)

14 OH 2 EB (FRP Polyester Bars)

15 OH 2 WB (Type 316 Stainless Steel Clad)

16 Other Ohio Projects 70 Columbus Wayne County US 30 (constructed 2005) Epoxy Dowels FRP Bars MMFX Bars Zinc-Plated Dowels 50 Athens Belmont County Route 7 (constructed 1983) 1.25-in FRP Bars

17 Current Findings Other Ohio Projects Bel 7 (28 years 1.25-in vinyl ester FRP and epoxy-coated dowels) Lower LTE s but relatively good performance of FRP (poor LTE s of full-depth repair with polyester resin FRP) Epoxy dowels LTE less than 70% - debonding of epoxy and some section loss US 30-Wayne Co. (2005, with DBI) Epoxy control, 2 sections, 7 and 6 joints; 3 MMFX joints; 3 zinc plated joints; 1 FRP Composite joint

18 Investigation of Older Epoxy- Coated Dowel Projects OH OH epoxy-coated dowel performance (14-28yrs) No apparent correlation between chloride content and corrosion Major problem delamination of epoxy coating and rusting and pitting of steel dowel some loss of section Estimated service life years Twelve cores of 1.25-in plastic-coated dowels Much better condition than epoxy coated after 33 years

19 Ohio Older Epoxy-Coated Dowels (CUY-176, 14 yrs)

20 Ohio Older Epoxy-Coated Dowels (BEL-7, 28 yrs)

21 Ohio Plastic-Coated Dowels Summit County Route 59 (constructed 1978) 1.25-in Plastic-Coated Bars 71 Allen County Route 81 (constructed 1978) 1.25-in Plastic-Coated Bars 70 Columbus Athens 77 50

22 Route 81, Allen County Recovered Dowel Bar Surface Condition

23 Route 59, Summit County Recovered Dowel Bar Surface Condition

24 Wisconsin 2 (Hwy 29, Owen) (constructed 1997) 94 Owen Wisconsin 2 Highway 29 EB, Owen to Abbotsford 29 Abbotsford 39 Nominal Design: 11-in JPCP ft Joints Dense aggregate base Dowel Bars: 1.5-in Epoxy 1.5-in FRP 1.5-in SS Tubes 1.5-in Solid SS Madison 94 Milwaukee

25 Current Findings Wisconsin WI 2 (12 years) Support marginal > 10 mils Concrete quality poor at crack face FRP (3 types marginal LTEs 60 s and 70 s) 2 polyester and 1 vinyl ester Hollow Filled Type 304 SS good LTE Type 304 solid stainless steel <60% LTE (1 joint)- poor concrete quality at joint Epoxy control generally > 85%

26 WI 2 (LTE vs. Dowel Type)

27 WI 2 Faulting

28 Investigation of Older Epoxy- Coated Dowel Projects WI WI epoxy-coated dowel performance (12-33 yrs) FWD testing 4 locations Coring bit poor quality Severe deterioration of crack face at joint 4 of 44 cores no dowel(1) or dowel bar end in core (3) inadequate embedment Corrosion not correlated to chloride content Extensive to moderate deterioration on projects 19 years or older Epoxy coating service life years

29 Chloride Concentration vs. Dowel Deterioration (Wisc)

30 Wisconsin Older Epoxy-Coated Dowels (USH 18/151, 20 yrs)

31 Wisconsin Older Epoxy-Coated Dowels (STH 67, 33 yrs)

32 General Comments Very small sample represented (OH and WI) Joint deterioration a concern concrete quality (see TPF-5(224) study) Need better documentation of dowel material properties particularly FRP but also SS Other factors [perm base support, joint sealant, construction quality (consolidation, dowel embedment length, early curl/warping stresses, epoxy-coating quality and/or damage during installation)] are also important

33 Summary and Recommendations Recommended testing approach involving FWD testing and coring of joints appears good. However, chloride content testing did not correlate with corrosion observed on older projects. Add coating thickness and knifecoating adhesion test (see TRR 2220)

34 Summary and Recommendations (cont d) LTE performance of 1.5-in polyester resin and e-glass not acceptable. Larger diameter vinyl ester resin and ECR-glass needed - Suggest 1.75-in for strong base support (unbonded concrete overlays) and service life > 50 years. Have AASHTO/ACI Materials Group develop guide spec (Mateen Dowel spec available). Evaluation of Type 304 (solid or mortar filled tubes) and 316 Stainless Steel clad dowels inconclusive due to short evaluation period.

35 Summary and Recommendations (cont d) Service life of epoxy coating on mild steel dowels appears to be in the year range. For longer life pavements more durable coating required. Plastic-coated dowels (2 projects) showed better performance than epoxy-coated dowels Due to small sample size and confounding factors, recommendations are based on a subjective evaluation of test results and other published literature

36 Draft Implementation Plan Evaluate long-term corrosion of epoxy-coated dowels (coring and FWD) in each state to determine corrosion protection performance. Use vinyl ester (not polyester) for FRP dowels Have AASHTO/ACI Materials Group develop generic spec for long-life FRP dowels. Improve quality control checks of epoxycoated dowels if continued to be used. Consider adopting plastic-coated dowels as standard on new projects.

37 Other Relevant Research Iowa Field and Lab studies Caltrans Lab and HVS West Virginia Lab and Field 2009 Final Report Mn/DOT Lab and Field Canada Lab and Field Quebec Report year plan to evaluate use of fiber composite materials in reinforcing bars and dowels nearing completion CPTP Tech Briefs on Long-Life Pavements and FRP Bars in CRCP

38 TPF-5(188) Final Report - Evaluation of Alternative Dowel Bar Materials and Coatings Data and related reports CD? Questions????