Development of an Improved Point Load Apparatus

개량형 점하중강도시험기의 개발

  • 김용필 (울산과학대학 공간디자인학부) ;
  • 엄정기 (부경대학교 에너지자원공학과)
  • Published : 2009.12.31

Abstract

The accuracy of point load apparatus is depend on point to point coaxial fitting. Also, the estimation of applied point load using the pressure gauge frequently lead to erroneous results. An improved point load apparatus has been developed in this study by mounting linear bearing on polished support rod, and eccentric error of point to point axis has been sustained less than 0.1 mm even under series of extreme work load conditions. Two digital displacement gauges are attached to measure the distance from point to point with sample specimen. A load cell mounted at the end of upper conical platen measure the applied net load on sample instead of preassure gauge. Total of 107 point load tests has been achieved to assure the quality and performance of developed apparatus. This exercise turned out to be successful.

Keywords

point load apparatus;rock strength

References

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