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Classification of arid soils for engineering purposes A pedological approach
Published in P.G. Fookes, R.H.G. Parry, Engineering Characteristics of Arid Soils, 2020
I.J. Smalley, T.A. Dijkstra, C.D.F. Rogers
West (1991) has recently reviewed the contemporary conventional position on the description and classification of engineering soils. He proposed that engineering soils can be considered to fall broadly into three groups: residual soils, transported soils, and what a geologist would call non-indurated rocks. Residual soils are those that have formed in place by the direct weathering of rocks. Transported soils have been carried to their present location by the action of some natural transporting agent such as water, ice or wind. Non-indurated rocks are often referred to as soils by the engineer. Examples are the Oxford Clay, the Keuper Marl, and some of the Cretaceous and Tertiary sand formations. A full description of soils comprises two parts: a description of the soil mass, which can only be made from exposures such as trial pits or in a more limited way from undisturbed samples, and a description of the soil material, which is made by examination of a disturbed sample of the soil. Two main key systems are used in the description and classification of engineering soils. These are the Unified Soil Classification (UCS) in North America and the British Soil Classification System (BSCS) in Britain, both of which generate names and descriptions based on simple laboratory tests. Neither seems particularly well suited to arid soil classification.
Geotechnical assessment strategy for bridge maintenance—case study
Published in Andreas Loizos, Imad L. Al-Qadi, A. (Tom) Scarpas, Bearing Capacity of Roads, Railways and Airfields, 2017
The geological plans indicate that the site is underlain by solid geology comprising mudstone of the Triassic Mercia Mudstone which is formerly known as Keuper Marl (Benton et al., 2002). Although not indicated on the geological plan, it is considered likely that made ground in the form of engineered fill for the approach road embankments, will overlay the solid geology at this location. This was confirmed by existing ground investigation factual and interpretative reports available for the site (M5 Motorway) and its vicinity (HAGDMS, 1982, 2002). In one of these reports, a borehole identified possible fill material to depths of between 1.35 m and 1.5 m below ground level (bgl) directly underlain by Mercia Mudstone Group, described as firm to stiff reddish brown and light grey friable silty clay with highly weathered mudstone lithorelicts (HAGDMS, 1982).
Durability and service life assessment
Published in James Douglas, Bill Ransom, Understanding Building Failures, 2013
Water freezing within the pores of concrete can cause disruption. Susceptibility to such attack is greatest with poor-quality concrete used in wholly exposed positions, such as kerbs and bridges. Good-quality, lowpermeability concrete, used in most building situations, is not affected. Frost resistance can be increased greatly through the judicious use of air-entraining agents. Water-soluble sulphates occur in some soils, notably the London, Oxford and Kimmeridge Clays, the Lower Lias and Keuper Marl. They may be present, too, in materials used as hardcore, for example, plastered brick rubble. These sulphates of calcium, magnesium and sodium can attack the cement matrix to give reaction products which have an increased volume, and thus cause expansion. This, in turn, can lead not only to spalling and surface scaling but also to more serious disintegration. The extent of damage will depend greatly upon the amount and types of sulphate present, the ground-water conditions and the quality of the concrete. Once again, poor-quality concrete will be affected more drastically than well-compacted concrete of low permeability. Considerable resistance to sulphate attack can be obtained by using sulphate-resisting Portland cement to BS 4027.
Stiffness and strength parameters for the hardening soil model of a reconstituted diatomaceous soil
Published in European Journal of Environmental and Civil Engineering, 2023
Raimundo Francisco Pérez León, Juan Félix Rodríguez Rebolledo, Bernardo Caicedo Hormaza
Janin et al. (2015) modelled the mechanical behaviour of phyllitic bedrock by the advanced elastoplastic HS model. Möller and Vermeer (2008) used HS to simulate the mechanical behaviour of stratigraphy composed of a humanmade fill, a weathered Keuper Marl and a lacustrine limestone layer in Stuttgart, Germany. They also used the HS model to simulate a stratigraphy composed of humanmade fill, sand and clay near Rotterdam, Netherlands.