Rocscience Coefficient of Restitution Table in RocFall

RN ( Normal ) RT ( Tangential ) Type Verification Location Reference
Min Max Mean Standard
Deviation
Min Max Mean Standard
Deviation
       
                       
0.370 0.420     0.870 0.920     Hard surface paving Tested using simulated
rockfalls of similar size and shape of a previous rockfall.
Glenwood Canyon, Colorado, USA Pfeiffer, T.J., and Bowen, T.D., "Computer Simulation of Rockfalls." Bulletin of Association of Engineering Geologists. Vol. 26, No. 1. 1989. pp135-146
0.330 0.370     0.830 0.870     Bedrock or boulders with little soil
or vegetation
0.300 0.330     0.830 0.870     Talus with little vegetation
0.300 0.330     0.800 0.830     Talus with some vegetation
0.280 0.320     0.800 0.830     Soft soil slope with little
vegetation
0.280 0.320     0.780 0.820     Vegetated soil slope
                       
    0.315 0.064     0.712 0.116 Limestone face Tested on restoration-blasting slopes made of four types of materials; blast-generated rock fragments, partially vegetated scree on berms, uncovered blast piles, and vegetated quarry waste. Limestone quarry in England Robotham, M.E., and Wang, H., and Walton, G., "Assessment of risk from rockfall from active and abandoned quarry slopes." Institution of mining and Metallurgy, Section A. 1995.104(Jan-April), pp A25-A33
    0.303 0.080     0.615 0.170 Partially vegetated limestone
scree
    0.315 0.064     0.712 0.116 Uncovered limestone blast pile
    0.251 0.029     0.489 0.141 Vegetated covered limestone pile
    0.276 0.079     0.835 0.087 Chalk face Chalk quarry in England
    0.271 0.018     0.596 0.085 Vegetated chalk scree
                       
    0.384 0.133     0.687 0.130 Wood platform slope at 45 degrees was used as a control for the field tests they did. Tested as control parameters Western North Carolina for
Interstate 40.
Wu, Shie-Shin "Rockfall evaluation by computer
simulation" Transportation Research Records.
Vol. 1031 pp 1-5, 1985.
                       
    0.200       0.530   Dolomitic limestone boulders on rocky surfaces and on talus desposits Consisted of hand made throws and free fall tests by fragmentation of rock using explosives, of dolomitic limestone boulders on rocky surfaces and on talus deposit of the landslide fans. Also used back-analysis, and information from Urciuoli. Atrani, Campania, Southern Italy Budetta, P., and Santo, A. "Morphostructural evolution and related kinematics of rockfalls in Campania(southern Italy)." Engineering Geology. Vol.36 pp197-210.
    0.100       0.200   Remolded pyroclastic from the terraces situated at the base of the cliff
    0.000       0.240   Impacts  on detritus of the fans  present at the foot of a rock cliff
                       
    0.393       0.567   Soil Tested by dropping 3 to 5 cm cuboid and angular granite rock fragments onto slopes Hong Kong Chau, K.T., and Wong, R.H.C., and Lee, C.F.
"Rockfall Problems in Hong Kong and some new
experimental results for coefficients of Restitution"
International Journal of rock mechanics and
mining sciences and geomechanics.
Vol. 35, Section 4-5. 1996. pp662-663
    0.453       0.737   Shotcrete
    0.487       0.910   Rock slope
                       
    0.500       0.950   Bedrock Referenced from tests carried out by Barbieri et al. Italcementi works at Castellammare
di Stabia(northern slope of the Sorrentine Peninsula), and the area of Atrani. 
Giani, G.P. "Rock Slope Stability Analysis"
Rotterdam, Balkema 1992.
    0.350       0.850   Bedrock covered by large blocks
    0.300       0.700   Debris formed by uniform
distributed elements
    0.250       0.550   Soil covered by vegetation
                       
    0.530       0.990   Clean hard bedrock     Hoek, Evert. "Unpublished notes" NSERC Industrial Research Professor of Rock Engineering, Department of Civil Engineering, University of Toronto, St George Street, Toronto, Ontario, Canada M5S 1A4
    0.400       0.900   Asphalt roadway
    0.350       0.850   Bedrock outcrops with hard surface, large boulders
    0.320       0.820   Talus cover
    0.320       0.800   Talus cover with vegetation
    0.300       0.800   Soft soil, some vegetation
                       
0.370 0.420             Smooth hard surfaces and paving Developed by observation and literature review Colordado, USA Pfeiffer, T.J., and Higgens, J.D.,  "Rockfall Hazard Analysis Using the Colorado Rockfall Simulation." Transportation Research Record 1288, TRB, National Research Council, Washington, D.C., 1990, pp117-126.
0.330 0.370             Most bedrock and boulder fields
0.300 0.330             Talus and firm soil slopes
0.280 0.300             Soft soil slopes
        0.870 0.920     Smooth hard surfaces such as
pavement or smooth bedrock surfaces
        0.830 0.870     Most bedrock surfaces and talus with no vegetation
        0.820 0.850     Most talus slopes with some low
vegetation
        0.800 0.830     Vegetated talus slopes and soil slopes with spares vegetation
        0.780 0.820     Brush covered soil slope
                       
    0.530 0.040     0.990 0.040 Clean Hard Bedrock a) rolled many rocks down the slope to verify used values b) comparison to historical rockfall events at site Mountain road, near Bolzano, Sothtyrol, Italy feedback from user of RocFall version 3
    0.350 0.040     0.850 0.040 Bedrock outkrop
    0.320 0.040     0.820 0.040 Talus cover
    0.320 0.040     0.800 0.040 Talus with vegetation
    0.400 0.040     0.900 0.040 Asphalt paving
                       
    0.530 0.040     0.990 0.040 Clean Hard Bedrock default program values used 170m deep open pit, Tasmania, Australia (overall pit angle between 55 and 65 degrees) feedback from user of RocFall version 3
    0.350 0.040     0.850 0.040 Bedrock outcrop
                     

 

    0.480 0.190     0.530 0.170 Concrete inverse calculation of paths - standard deviations seemed to large Takamatsu, Japan feedback from user of RocFall version 3
    0.470 0.300     0.550 0.230 Weathered Rock
    0.480 0.000     0.530 0.000 Concrete inverse calculation of paths, roughness of 7.9 degrees for concrete, 9.3 for rock
    0.470 0.000     0.550 0.000 Weathered Rock
    0.850 0.000     0.530 0.000 Concrete inverse calculation of paths
    1.000 0.000     0.550 0.000 Weathered Rock
                       
    0.530 0.040     0.990 0.040 Bedrock Estimation, block diameters 10 to 30 cm Fjord valley, State of Sogn og Fjordane, Norway feedback from user of RocFall version 3
    0.500 0.060     0.700 0.060 Blockfield
    0.500 0.060     0.650 0.060 Blockfield with bushes and small
trees
    0.500 0.060     0.500 0.060 Blockfield with forest
    0.300 0.060     0.800 0.060 Top-soil with vegetation
    0.400 0.040     0.900 0.040 Asphalt paving
    0.350 0.040     0.850 0.040 Gravel road
                       
    0.500       0.800   Sparsely forested slope is covered by a veneer of very fine weathered talus derived from weak shistose units underlying the limestone cap. Calculated from historic rockfall Sunnybrae, (interior of )British Colombia, Canada Hungr, O. and Evans, S.G. 1988. Engineering evaluation of fragmental rockfall hazards. Proc. 5th International Symposium on Landslides, Lusanne.  July 1988, Vol. 1, pp. 685-690.
    0.500       0.800   Limestone on bare uniform talus slope formed of basalt fragments with a modal size of 5 cm. Calculated from historic rockfall Hedley, (southern interior of ) British Colombia, Canada
    0.700       0.900   rectangular bolder of metamorphosed tuff on bare rock and a steep snow covered shelf. Calculated from historic rockfall Squamish Highway, north of Vancouver British Colombia, Canada