OR/15/065 Appendix 4 - Bulking of soils & rocks classification descriptions

Entwisle, D, Lee, K A, and Lawley, R S. 2015. User guide for ‘BGS Civils’ - a suite of engineering properties datasets. British Geological Survey Internal Report, OR/15/065.

Bulking class and nominal bulking factor range with typical lithology characteristics

Class	Typical class lithology	Bulking factor (%)
1	Sand and/or gravel, very soft to soft clay or silt.	5 to 20
2	Firm (and stiffer) clay and silt, mudstones that break-up easily during excavation, peat.	20 to 40
3	Weaker rocks that are likely to break into a wide variety of particle sizes, sand to cobble or even boulder.	40 to 55
4	Medium strong rocks (and stronger) that are likely to break into a variety of blocks sizes and block shapes.	50 to 65
5	Strong (and stronger) rocks that form generally blocky material when excavated.	>65
6	Not applicable, relates to non-geological deposits e.g. water bodies.	N/A

Bulking factors from literature

Rock class	Lithology	Inital bulk density Mg/m3	Bulking factor %	Reference
Igneous rock	Andesite	2.94	67	Church (1981)
	Tuff	2.40	50	Church (1981)
	Basalt	2.94	64	Church (1981)
	Basalt	2.4 to 3.1	75 to 80	Engineering tool box
	Basalt	2.95	64	Durham University
	Diabase	3.00	67	Church (1981)
	Diorite	3.1	67	Church (1981)
	Felsite	2.5	67	Church (1981)
	Gabbro	3.1	67	Church (1981)
	Granite	2.675	50 to 86	Hartman (1992)
	Granite and porphyry	2.72	75	Hartman (1992)
	Granite	2.6 to 2.8	75 to 80	Engineering tool box
	Granite	2.41	72	Durham University
	Rhyolite	2.40	67	Church (1981)
	Igneous		50 to 80	Horner, 1988
Metamorphic rocks	Gneiss	2.70	67	Church (1981)
	Gneiss	2.69	75	Hartman (1992)
	Gneiss	2.69	75 to 80	Engineering tool box
	Marble	2.68	67	Church (1981)
	Marble	2.72	68 to 75	Hartman (1992)
	Quartzite	2.68	67	Church (1981)
	Schist	2.69	67	Church (1981)
	Slate	2.67	77	Church (1981)
	Slate	2.72 to 2.88	29 to 30	Hartman (1992)
	Slate	2.6 o 3.3	85 to 90	Engineering tool box
	Metamorphic		30 to 65	Horner, 1988
Sedimentary rock	Breccia	2.4	33	Church (1981)
	Conglomerate	2.21	33	Church (1981)
	Sandstone	2.31 to 2.45	39 to 50	Hartman (1992)
	Sandstone	2.42	61	Church (1981)
	Sandstone	2.1 to 2.4	75 to 80	Engineering tool box
	Sandstone	2.5	60	Durham University
	Sandstone	2.65	61	Durham University
	Shale	2.64	50	Church (1981)
	Shale	2.35	50	Durham University
	Siltstone	2.42	61	Church (1981)
	Limestone	2.60	63	Church (1981)
	Limestone (blasted)	2.5	68 to 75	Hartman (1992)
	Limestone	2.7 to 2.8	75 to 80	Engineering tool box
	Limestone	2.6	63	Durham University
	Dolomite	2.8	50 to 60	Engineering tool box
	Dolomite	2.88	67	Church (1981)
	Chalk	1.85	50	Durham University
	Chalk	2.2	30 to 45	January.id.au
	Chalk	2.41	33	Church (1981)
	Chalk		30 to 40	Horner, 1988
	Sedimentary		40 to 75	Horner, 1988
Soil	Clay	1.75	33	Hartman (1992)
	Clay	1.778	34	Hartman (1992)
	Clay	1.75 to 1.78	30 to 40	Engineering tool box
	Clay dry	1.362	25	Hartman (1992)
	Clay damp	1.99	40	Church (1981)
	Clay	1.8 to 2.6	20 to 40	Engineering tool box
	Clay	1.6 to 2.1	20 to 40	Engineering tool box
	Clay (low PI)	1.65	30	Durham University
	Clay (high PI)	2.1	40	Durham University
	Clay and gravel dry	1.602	41	Hartman (1992)
	Clay and gravel wet	1.826	41	Hartman (1992)
	Clay with gravel	1.8	35	Durham University
	Clay and silt (fine)		20 to 40	Horner, 1988
	Silt (loam) dry	1.80	35	Church (1981)
	Silt (loam) damp	2	40	Church (1981)
	Mud	1.28 to 1.76	21	Hartman (1992)
	Mud	1.76 to 2.08	20 to 21	Hartman (1992)
	Mud	1.745	0	Church (1981)
	Loess, dry	1.911	35	Church (1981)
	Loess, moist	1.99	40	Church (1981)
	Silt (loam)		15 to 25	Engineering tool box
	Sand dry	1.30	10 to 16	Hartman (1992)
	Sand moist	2.018	15	Hartman (1992)
	Sand	2.00	5	Durham University
	Sand, wet	2.0	20 to 30	Engineering tool box
	Sand, dry	1.8	20 to 30	Engineering tool box
	Uniform sand	1.6 to 2.1	10 to 15
	Well-graded sand	1.7 to 2.2	10 to 15
	Sand and gravel dry	1.97	14	Hartman (1992)
	Sand and gravel, wet	2.31	15	Hartman (1992)
	Sand and gravel	1.95	15	Durham University
	Sand or gravel (coarse)		10 to 15	Horner, 1988
	Gravel	1.7 to 2.3	10 to 15	Engineering tool box
	Gravel Dry	1.79	15	Church (1981)
	Gravel, dry	1.46 to 1.92	12	Hartman (1992)
	Gravel wet	2.01	5	Church (1981)
	Gravel wet	2.31	10	Hartman (1992)
	Gravel	2.1	5	Durham University
	Peat/topsoil	1.1 to 1.4	25 to 45	Horner, 1988