Strength and Permeability of an Ultra-Large Specimen of Granitic Rock.

摘要

Laboratory tests were conducted to measure the mechanical and transport properties of a 1-m-diameter by 2-m-high specimen of jointed granitic rock. Uniaxial loading was applied and radial permeability tests were made at various stress levels. Ultimate strength of the specimen was estimated prior to loading by testing small 52 mm diameter cores with similar fracture patterns. It was found that deformabilities of the large and small specimens were similar; however, the uniaxial strength of the large core was about 10% of that predicted. Although the large core contained a complex joint system, its overall permeability was dominated by a single open fracture normal to the axis. Using a simple parallel-plate analog, changes in the equivalent single-fracture aperture under load were significantly less than closures measured by means of linear variable differential transformers situated across the main fracture. 11 references. (ERA citation 08:052565)