Experimental study on strength of core specimen of CSGR in Shaping I hydropower station

Abstract

Core drilling method is one of the most commonly used method in the field detection of cemented sand gravel and rock engineering, which has the characteristics of intuition, accuracy and reliability. Based on the on-site drilling core sample of Shaping first-stage power station, the compressive strength of the specimens with diameters of ϕ150 mm, ϕ180 mm and ϕ219 mm and diameter-height ratios of 1∶2, 1∶1 and 2∶1 was tested. The strength difference between the standard cube specimen and the core sample specimen was compared and analyzed. The Grubbs test method was used to judge the discrete outliers in the compressive strength of the specimen. The regression equations of core sample strength and standard specimen strength under different diameters and diameter-height ratios were established. The result show that under the same diameter, the compressive strength increases with the increase of the ratio of diameter to height. Under the same diameter-height ratio, the compressive strength increases with the increase of diameter. The conversion coefficient of core sample strength obtained by research can be applied to the field quality inspection and identification of cemented sand and gravel engineering, and has strong application value.

Keywords

cemented sand gravel and rock / core drilling method / compressive strength / abnormal value test / diameter-height ratio