Granitic saprolites are abundant in many regions around the world and they are widely employed in various engineering projects. Behavior of such kinds of soils is not sufficiently understood and our knowledge about the fundamental behavior of saprolites is to a far less extent than the sedimentary soils. Owing to the limited knowledge, many problems occurred in the engineering applications that used saprolites as a construction material. This study presents results of a set of conventional drained and undrained triaxial compression shearing tests on the granitic saprolites in both the disturbed and undisturbed conditions. This study showed that the soil fabric was the paramount factor governing on the soil stress–strain response rather than the soil bonds. Under the drained shearing condition, the undisturbed soil revealed a strain-softening behavior with a dilative response at the low consolidation stress level, while a contractive response was present at the high consolidation stress levels. However, the disturbed soil showed a strain-hardening behavior with a contractive response, regardless of the consolidation stress levels during the drained shearing. The undrained response was complicated, as the soil showed both the contractive and dilative responses with phase transformation points, regardless of the soil condition (i.e., disturbed or undisturbed) and the consolidation stress levels. The bond effect of the intact soil persisted during the consolidation stage; however, its effect did not extend to the large strain-controlled shearing stage, where the tangential stiffness suddenly decreased at the axial strain of 1.5%.
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Altuhafi F, Baudet BA, Sammonds P (2010) The mechanics of subglacial sediment: an example of new “transitional” behaviour. Can Geotech J 47(7):775–790
Burland JB (1990) On the compressibility and shear strength of natural clays. Géotechnique 40(3):329–378
Cabalar A, Demir S, Khalaf M (2021) Liquefaction resistance of different size/shape sand-clay mixtures using a pair of bender element–mounted molds. J Testing Eval 49(1) (in press)
Chiu CF, Ng CWW (2014) Relationships between chemical weathering indices and physical and mechanical properties of decomposed granite. Eng Geol 179:76–89. https://doi.org/10.1016/j.enggeo.2014.06.021
Elkamhawy E, Wang H, Zhou B, Yang Z (2018) Failure mechanism of a slope with a thin soft band triggered by intensive rainfall. Environ Earth Sci 77(9):340. https://doi.org/10.1007/s12665-018-7538-8
Elkamhawy E, Zhou B, Wang H (2019a) Mineralogy, micro-fabric and the behavior of the completely decomposed granite soils. Civ Eng J 5(12):2762–2772
Elkamhawy E, Zhou B, Wang H (2019b) Transitional behavior in well-graded soils: an example of completely decomposed granite. Eng Geol 253:240–250. https://doi.org/10.1016/j.enggeo.2019.02.027
Frazier C, Graham R (2000) Pedogenic transformation of fractured granitic bedrock, southern California. Soil Sci Soc Am J 64(6):2057–2069
Fung WT (2001) Experimental study and centrifuge modeling of loose fill slope. M. Philosopy Thesis, the Hong Kong Univ. of Science and Technology, Hong Kong
Futai MM, Almeida MSS, Lacerda WA (2004) Yield, strength, and critical state behavior of a tropical saturated soil. J Geotech Geoenviron Eng 130(11):1169–1179
Gan JKM, Fredlund DG (1996) Shear strength characteristics of two saprolitic soils. Can Geotech J 33(4):595–609
GEO (2017) Geoguide 3—guide to rock and soil descriptions. Geotechnical Engineering Office, Civil Engineering Department, The Government of the Hong Kong Special Administrative Region
Head KH (1992) Manual of soil laboratory testing, vol 3. John Wiley and Sons, New York
Ietto F, Perri F, Cella F (2018) Weathering characterization for landslides modeling in Granitoid rock masses of the Capo Vaticano promontory (Calabria, Italy). Landslides 15(1):43–62. https://doi.org/10.1007/s10346-017-0860-5
Ladd R (1978) Preparing test specimens using undercompaction. Geotech Test J 1(1):16–23
Lee I.-K (1991) Mechanical behaviour of compacted decomposed granite soil. Unpublished Doctoral thesis, City University London
Lee I, Coop M (1995) The intrinsic behaviour of a decomposed granite soil. Géotechnique 45(1):117–130
Liu P, Zhou X, He Y (2015) Bond yield characteristics of undisturbed completely decomposed granite. Adv Mater Sci Eng 2015:7
Lumb P (1962) The properties of decomposed granite. Géotechnique 12(3):226–243. https://doi.org/10.1680/geot.19220.127.116.11
Ng CWW, Chiu ACF (2001) Behavior of a loosely compacted unsaturated volcanic soil. J Geotech Geoenviron Eng 127(12):1027–1036. https://doi.org/10.1061/(ASCE)1090-0241(2001)127:12(1027)
Ng CWW, Chiu ACF (2003) Laboratory study of loose saturated and unsaturated decomposed granitic soil. J Geotech Geoenviron Eng 129(6):550–559. https://doi.org/10.1061/(ASCE)1090-0241(2003)129:6(550)
Ng CWW, Fung WT, Cheuk CY, Zhang L (2004) Influence of stress ratio and stress path on behavior of loose decomposed granite. J Geotech Geoenviron Eng 130(1):36–44. https://doi.org/10.1061/(ASCE)1090-0241(2004)130:1(36)
Nguyen M (2016) Soil liquefaction: a critical state approach 2nd edition. Proc Inst Civ Eng Geotech Eng 169(3):317–317
Rocchi I, Coop MR (2016) Mechanisms of compression in well-graded saprolitic soils. Bull Eng Geol Env 75(4):1727–1739. https://doi.org/10.1007/s10064-015-0841-7
Rocchi I, Todisco M, Coop MR (2015) Influence of grading and mineralogy on the behaviour of saprolites. Adv Soil Mech Geotech Eng: proceedings of the 6th international symposium on deformation characteristics of geomaterials. IOS press, Amsterdam, pp. 415–422
Rocchi I, Coop MR, Maccarini M (2017) The effects of weathering on the physical and mechanical properties of igneous and metamorphic saprolites. Eng Geol 231(Supplement C):56–67
Scarciglia F, Le Pera E, Critelli S (2005) Weathering and pedogenesis in the Sila Grande Massif (Calabria, South Italy): from field scale to micromorphology. CATENA 61(1):1–29
Skempton AW (1954) The pore-pressure coefficients A and B. Géotechnique 4(4):143–147. https://doi.org/10.1680/geot.1918.104.22.168
Thevanayagam S (1998) Effect of fines and confining stress on undrained shear strength of silty sands. J Geotech Geoenviron Eng 124(6):479–491
Thevanayagam S, Martin GR (2002) Liquefaction in silty soils—screening and remediation issues. Soil Dyn Earthq Eng 22(9):1035–1042
Thevanayagam S, Veluchamy V, Huang Q, Sivaratnarajah U (2016) Non-plastic silty sand liquefaction, screening, and remediation. Soil Dyn Earthq Eng 91:147–159
Verdugo R, Ishihara K (1996) The steady state of sandy soils. Soils Found 36(2):81–91
Wang YH, Yan WM (2006) Laboratory studies of two common saprolitic soils in Hong Kong. J Geotech Geoenviron Eng 132(7):923–930. https://doi.org/10.1061/(ASCE)1090-0241(2006)132:7(923)
Yan WM (2003) Experimental study and constitutive modelling of re-compacted completely decomposed granite. M. Philosopy Thesis, the Hong Kong Univ. of Science and Technology, Hong Kong
Yan WM, Li XS (2011) A model for natural soil with bonds. Géotechnique 61(2):95–106
Yan WM, Li XS (2012) Mechanical response of a medium-fine-grained decomposed granite in Hong Kong. Eng Geol 129:1–8. https://doi.org/10.1016/j.enggeo.2011.12.013
The authors are grateful to the National Natural Science Foundation of China (NSFC) for the research Grant (Nos. 416772267 and 51508216, 41931286).
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Elkamhawy, E., Zhou, B. & Wang, H. Experimental investigation of both the disturbed and undisturbed granitic saprolite soil. Environ Earth Sci 79, 276 (2020). https://doi.org/10.1007/s12665-020-09026-y
- Soil fabric
- Granitic saprolite
- Bond yield