Use of Free-Free Resonant Column Testing for Characterizing Infrastructure Materials

Transcription

1 UW Madison Geological and Geotechnical Engineering Geological Engineering Transporta1on Geotechnics Civil & Environmental Engineering Use of Free-Free Resonant Column Testing for Characterizing Infrastructure Materials Andrew Keene, Zhipeng Su, Dante Fratta, and James Tinjum University of Wisconsin- Madison Slide 1

2 Outline 1. Background Resilient modulus testing Free-free resonant column testing 2. Materials 3. Methods Seismic modulus test development 4. Results Fitting parameters Summary seismic/resilient modulus Curing detection 5. Conclusion University of Wisconsin- Madison Slide 2

3 Background: Resilient Modulus Resilient Modulus (M r ) Test M r = σ d / ε r ε r = δ e /L σ d Example: δ e L where ε r is the recoverable elastic strain and σ d is the deviator stress Section NCHRP 1-28A (2004) University of Wisconsin- Madison Slide 3

4 Background: Resilient Modulus Power Function: σ 1 k 1 and k 2 = fitting parameters θ = bulk stress θ = σ 1 +2(σ 3 )=1 p r = reference stress σ 1 log (resilient modulus) k 1 (σ c =35 kpa) Summary Resilient σ 3 σ Modulus, SM 3 r 1 k 2 σ 3 σ 3 (Huang 2004; Moosazedh & Witczak 1981) log (bulk stress) University of Wisconsin- Madison Slide 4

5 Background: Free-Free Resonant Column V P Accelerometer Impact Hammer Density, ρ P- Wave Velocity Length, L Constrained Modulus (Pucci 2010; Kalinski & Thummaluru 2005; Meng 2003) University of Wisconsin- Madison Slide 5

6 Materials Natural Aggregate and Recycled Base Course Minnesota DOT Class 5 natural aggregate Natural base course aggregates from Senegal Africa Recycled Concrete Aggregates (RCA) Recycled Asphalt Pavement (RAP) Recycled Asphalt Shingles (RAS) with Bottom Ash (BA) Railroad Substructure Materials Ballast Subballast Stabilized Infrastructure Materials Polyurethane-Stabilized Ballast (PSB) Rigid-Polyurethane Foam (RPF) Cement-Stabilized Silt University of Wisconsin- Madison Slide 6

7 Methods: Constrained (Seismic) Modulus Power Func(on: β-exponent Constrained Modulus, M (kpa) 0.6 3, , , , , V S,V P,σ 3 Summary Seismic Modulus, SM S R² = Confining α-coefficient Pressure (m/s) (kpa) σ 3 (Pucci 2010; Kalinski & Thummaluru 2005; Meng 2003) University of Wisconsin- Madison Slide 7 σ 3 Constrained Modulus σ 3 = σ c V s V P

8 Results: Resilient Modulus Fitting Parameters K 2 -exponent Fine-grained soils Coarse-grained and stabilized soils k 2 = x k R² = ,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 K 1 -coefficient Class 5 TxRCA-1_Day TxRCA-7_Day Subballast CaRAP CaRCA BAS GNB GRB MiRCA NjRCA RAS-25%, BA-75% PSB-C3 PSB-C6 (Moosazedh & Witczak 1981) RCA = Recycled Concrete Aggregates RAP = Recycled Asphalt Pavement Tx = Texas Ca = California Mi = Michigan Nj = New Jersey PSB = Polyurethane Stabilized- Ballast RAS = Recycled Asphalt Singles BA = Bottom Ash BAS, GNB, GRB are unbound base course materials from Senegal Africa University of Wisconsin- Madison Slide 8

9 Results: P-wave Velocity Fitting Parameters β-exponent Fine-grained soils V S β = α R² = 0.86 Coarse-grained and stabilized Soils α-coefficient (m/s) V P Class 5 TxRCA TxRCA-7_Day Subballast Clean Ballast BAS GNB GRB CaRCA NjRCA NjRCA-7_Day Ottawa Sand CaRAP RPF-2 RPF-3 (Pucci 2010; Kalinski & Thummaluru 2005; Meng 2003) RCA = Recycled Nj = New Jersey Concrete Aggregates PSB = Polyurethane RAP = Recycled Stabilized-Ballast Asphalt Pavement RPF = Rigid- Tx = Texas Polyurethane Foam Ca = California Mi = Michigan BAS, GNB, GRB are unbound base course materials from Senegal Africa University of Wisconsin- Madison Slide 9

10 Results: Material Comparison Constrained Modulus, M (MPa) 1,400 1,200 1, ,400 TxRCA M R² = ,200 1,000 Class 5 M R² = TxRCA M R 600 σ 3 = 35 kpa R² = Class 5 M R 200 R² = Confining Pressure σ 3 (kpa) Resilient Modulus, M R (MPa) University of Wisconsin- Madison Slide 10

11 Results: Modulus Comparisons kpa Resilient Modulus (MPa) kpa σ 3 R² = 0.99 R² = 0.95 TxRCA 50 Less Stiff More Stiff Class ,000 1,200 1,400 1,600 Confining Pressure σ 3 (kpa) University of Wisconsin- Madison Slide 11

12 Results: Modulus Comparison 400 Resilient Modulus, SM R (MPa) SM R = 0.39 SM S R² = Constrained Modulus, SM S (MPa) σ 3 = representative confining pressure at 35 kpa University of Wisconsin- Madison Slide 12

13 Results: TxRCA Curing 2,500 Constrained Modulus, M (kpa) 2,000 1,500 1, M = 179 σ R² = 0.89 M = 41 σ R² = 0.99 TxRCA 7Day TxRCA 1Day Confining Pressure, σ 3 (kpa) σ 3 = confining pressure (kpa); M = constrained modulus (kpa) University of Wisconsin- Madison Slide 13

14 Results: Silt Cement Curing Natural Freqency, f n (Hz) 2,000 1,800 1,600 1,400 1,200 1, f n = 1408 σ R² = 0.88 f n = 1076 σ R² = 0.93 f n = 463 σ R² = Confining Pressure (kpa) 28 Day 7 DAy 1 Day σ 3 = confining pressure; f n = natural frequency (Hz) University of Wisconsin- Madison Slide 14

15 Conclusions Effects of Confining Pressure Mr vs. σ conf M vs. σ conf Mr and V P Fitting Parameters Mr vs. M SMr vs. SM S Curing M vs. σ conf RCA re-cementation effects Natural frequency vs. σ conf cement soil University of Wisconsin- Madison Slide 15

16 Questions? Acknowledgements References Center for Freight Infrastructure Research and Education (CFIRE) Minnesota Department of Transportation Recycled Materials Resource Center (RMRC) Uretek USA Inc. Professors: Tuncer Edil Craig Benson Huang, Y.H. (2004). Pavement Analysis and Design Second Addition. Pearson Prentice Hall, Upper Saddle River, New Jersey. Kalinski, M.E. & Thummaluru, M.S.R. (2005). A New Free-Free Resonant Column Device for Measurement of Gmax and Dmin at Higher Confining Stresses. ASTM Geotechnical Testing Journal, Vol. 28, No. 2. Menq, F. Y. (2003). Dynamic Properties of Sandy and Gravelly Soils. PhD thesis, Department of Civil, Architectural and Environmental Engineering, University of Texas, Austin, Moosazedh, J. & Witczak, M. (1981). Prediction of Subgrade Moduli for Soil that Exhibits Nonlinear Behavior. Journal of Transportation Research Board, No.810, Washington, D.C., pp National Cooperative Highway Research Program, NCHRP. (2004). Laboratory Determination of Resilient Modulus for Flexible Pavement Design. Research Results Digest, Transportation Research Board. Pucci, M. J. (2010). Development of a Multi-Measurement Confined Free-Free Resonant Column Device and Initial Studies. MS thesis, Department of Civil, Architectural, and Environmental Engineering, University of Texas, Austin, University of Wisconsin- Madison Slide 16