1 2 1 2 1. 1) 50 o C 2. 21 2009 6 29 2017 5 8 28 2016 4 50 o C -20 o C Temperature ( o C) 27,ARP,2016 14,OCT,2016 23,MAR,2017 Elapsed time (day) Corn penetration length of soil hardness meter (mm) 27,ARP,2016 14,OCT,2016 Elapsed time (day) 23,MAR,2017 Improvement for cyclic undrained strength of sandy soils by mixing recycled asphalt pavement material Shoji Yokohama 1 and Atsuko Sato 2 ( 1 Hokkaido University, 2 Civil Engineering Research Institute for Cold Region, PWRI) Cyclic undrained strength, Recycled asphalt pavement material, Sandy soil, Bonding effect
Percent passing (%) Grain size (mm) RAP Recycled asphalt pavement material (RAP) s (Mg/m 3 ) dmax (Mg/m 3 ) dmin (Mg/m 3 ) F c (%) M As/M s (%) 2.366 1.607 1.412 --- 100 Volcanic soil () 2.453 1.005 0.778 6.15 0 RAP and mixture () 2.466 1.306 1.038 3.11 50 Toyoura sand () 2.649 1.636 1.344 --- 0 RAP and mixture () 2.516 1.805 1.462 --- 50 1 10 2016 4 27 2017 3 23 3. Recycled asphalt pavement materialrap RAP RAP 70 mm D max 9.5 mm 75 m M As M s M As /M s 50 0.25 mm dmax dmax RAP 2014 8 2) RAP 10 mm RAP 138 600 o C 26 4. 70mm 150mm CO 2 200 kpa B 0.95 1.010-4 %/min 50 o C
Actuator Transducer for excess pore water Belt-shaped pressure Dial gauge heater 65 o C Load cell Air compressor Specimen Burette Transducer for cell pressure dc =1.155Mg/m 3 Data logger for 65 o C 50 o C temperature inside the specimen 5. 5-1 d /2 c DA 5 N c D rc 5070 d c c =50100 kpa Cyclic loading As-T sand RAP RAP RAP Preparing and saturating Isotropic consolidation ( =50kPa) =1.143(Mg/m 3 ), =1.155(Mg/m 3 ) *Temperature of belt-shaped heater : 65 o C c =50 100 kpa a N c Elapsed time (hour) Cyclic undrained triaxial test =70.2-73.4%, DA=5% (kpa) c =50 100 kpa =53.5~62.6% 50 100 u/ c N c =48.3~59.1% RAP c =50 kpa u/ c =0.95 ---- =52.8~67.4% c =100 kpa =51.7~69.7% u/ c Number of loading cycles Temperature at center of the specimen (C o ) Cyclic stress ratio /2 (DA<1%)
Cyclic undrained triaxial test ( c=50kpa) Cyclic undrained triaxial test ( c=100kpa) Compression Axial strain, (%) : =59.8%, /2 c =0.116 : =62.8%, /2 c=0.123 Extension Number of loading cycles, Number of loading cycles, Cyclic undrained triaxial test ( c =50kPa) Cyclic undrained triaxial test ( c =100kPa) ( =59.8%, /2 c=0.116) ( =55.0%, /2 c=0.100) ( =62.8%, /2 c=0.123) ( =58.9%, /2 c =0.090) Number of loading cycles, Number of loading cycles, Excess pore water pressure ratio, Axial strain, (%) Excess pore water pressure ratio, ( =55.0%, /2 c =0.100) ( =58.9%, /2 c=0.090) c =50 kpa RAP RAP 5-2 c =50100 kpa d /2 c DA 5 N c D rc 50 50 o C 50 o C
50 o C (b) c =100 kpa 50 o C 50 o C 50 kpa 100 kpa 4) RAP 50 o C c =50 100 kpa d /2 c=0.2 50 o C a N c 50 o C 50 o C (a) c =50 kpa c =50 100 kpa u/ c N c c =50 kpa u/ c =0.95 50 o Cu/ c =0.95 50 o C c =100 kpa Cyclic stress ratio /2 (DA<1%) Cyclic undrained triaxial test, ( =50kPa) DA=5% (T=50 o C) (T=50 o C) Number of loading cycles Number of loading cycles Cyclic undrained triaxial test ( Cyclic undrained triaxial test ( c =00kPa) c=50kpa) ( =56.1%, /2 c =0.217) ( =60.9%, /2 c=0.208) (T=50 o C) ( =50.5%, /2 c =0.212) (T=50 o C), ( =47.4%, /2 c=0.204) ( =50.5%, /2 c=0.212) ( =62.4%, /2 c =0.221) Number of loading cycles, Number of loading cycles, Axial strain, (%) Cyclic stress ratio /2 (DA<1%) Axial strain, (%) Cyclic undrained triaxial test, ( =100kPa) DA=5%
Cyclic undrained triaxial test ( c=50kpa) Cyclic undrained triaxial test ( c=100kpa), ( =56.1%, /2 c =0.217) ( =60.9%, /2 c =0.208) (T=50 o C),( =50.5%, /2 c =0.212) (T=50 o C), ( =47.4%, /2 c =0.204) ( =50.5%, /2 c ( =62.4%, /2 c=0.221) Number of loading cycles, Number of loading cycles, Excess pore water pressure ratio, c (kpa) 50 100 (T=50 o C) 1)3) 50 o C F c M As /M s F c M As /M s =0 c =50kPa 2 Mixing ratio, M As /M s M As /M s =50%F c 1.2% M As /M s =50% F c 3)5) Increment of finer content, F c (%) Excess pore water pressure ratio, 6. (1) (2) (3) 28 1) Matsumura, S.Miura, S.Yokohama, S.Kawamura, S. : Cyclic deformation-strength evaluation of compacted volcanic soil subjected to freeze-thaw sequence, Soils and Foundations, Vol.55, No.1, pp.86-98, 2015. 2) 11 pp.289-274 2015 3) No.694/III-57pp.305-312001 4) Vol.3pp.207-2151998 5) Lee, K. L., : Adhesion bonds in sands at high pressure, Proc. of ASCE, Vol. 103, No. GT8, pp.908-913, 1977.