Engineering Properties of Soil and Rock: The engineering or physical properties <br /> of soil and rock depend on both the material, or grain, properties and their in-situ, or <br /> undisturbed, texture, packing, particle orientation, and degree of saturation. Shear strength, <br /> compressibility, void ratio, permeability, and erodibility aze most often the engineering <br /> properties of interest. The engineering characteristics of an in-situ rock mass most often <br /> focus on discontinuities, such as bedding, sheaz zones, and fractures. Such features aze <br /> described in terms of frequency, attitude, spacing, roughness, bonding quality, and general <br /> continuity. <br /> Ezpansive Soil: Soils containing expansive clay minerals, such as, but not limited <br /> to, montmorillonite, which expands excessively when subjected to a moisture increase and <br /> which shrinks. excessively when subjected to a moisture decrease. Soils identified in the <br /> Natural Resources Conservation Services soil manual as having a high shrink-swell potential <br /> shall be considered expansive soils. <br /> Indez Properties of Soil or Rock: The soil material or grain properties of the <br /> material itself, regardless of the in-situ, or undisturbed, texture, packing, orientation, or . <br /> degree of saturation. The soil material properties of significance are the properties of the <br /> individual grains or particles, including the distribution of grain sizes, the shape, angularity, <br /> and hazdness of individual grains, the amount and type of clay minerals, and the presence and <br /> amount of organics. The rock material properties include color, texture, degree of <br /> weathering, hazdness, and geologic origin. The soiUrock material properties are used to <br /> indicate, or infer, potential engineering behavior. <br /> Intact Character of Rock: In the Eugene/Springfield area, rock units aze Tertiary <br /> in age -between 1.64 million years (My) and 35 My old. Rock units are classified on the <br /> basis of origin, whether igneous (intrusive or extrusive) sedimentary (marine or terrestrial), <br /> pyroclastic, or metamorphic; geologic name; color and texture {grain size); hardness; degree <br /> of weathering; and if available, degree of fracturing. <br /> Pistol-Butt (on Tree): Also called gun-stocked tree. A curved basal section of <br /> trunk, resulting from down-slope rotation of the base of the tree. Similaz in shape to curved <br /> butts on antique side arms. <br /> Qualified Registered Professional: An Oregon Registered Professional Engineer. <br /> (per ORS 672.002 to 672.325), who by training, education, and having a minimum of four <br /> years geotechnical experience, is especially qualified to apply the principles of soil <br /> mechanics, rock mechanics, hydraulics, and geological science to planning and evaluating <br /> engineering site investigations, making appropriate quantitative analyses and engineering <br /> design recommendations for that part of civil works involving the use of soil and rock <br /> materials and the inspection or testing of the construction thereof; and an Oregon Certified <br /> Engineering Geologist (per ORS 672.505 and 672..525), who by training, education, and <br /> experience is especially qualified to apply geologic data, principles and interpretation to <br /> naturally occumng materials so that geologic factors affecting planning, design, construction <br /> and maintenance of civil engineering works are properly recognized and utilized. <br /> Representative Sample: A soil sample taken from the site that has been disturbed <br /> or altered, completely or partially in-situ particle structure, by the remolding action of the <br /> sampling device but which contains all of the soil components in their in-situ amounts. <br /> Significant Structures and/or Facilities: All pavement structures for arterial and <br /> <br /> Administrative Order - 2 <br /> r:ladminord~rules\02geotech 1 ao.wpd(09/05/02) <br /> <br />