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Effect of Joint Sets on the Earth Pressure against the Support System in a Jointed Rock Mass

절리형성 암반지층 굴착벽체에 작용하는 토압에 대한 절리군의 영향

  • Received : 2015.10.07
  • Accepted : 2015.12.09
  • Published : 2015.12.31

Abstract

This study examined the magnitude and distribution of earth pressure on the support system in a jointed rock mass due to the different joint sets as well as varying the rock type and joint condition (joint shear strength and joint inclination angle). Based on a physical model test and its numerical simulation, a series of numerical parametric analyses were conducted using a discrete element method. The results showed that the induced earth pressure was affected significantly by a joint set depending on the inclusion of the joint inclination angle, which induces a joint sliding condition, but the number of joint sets alone was not important, even though the earth pressure could be increased slightly as the number of joint sets is increased. In addition, the study results were compared with Peck's earth pressure for soil ground, which indicated that the earth pressure in a jointed rock mass could be considerably different from that in soil ground. The study suggests that the effects of joint sets as well as rock type and joint condition are important factors affecting the earth pressure in a jointed rock mass and they should be considered when designing a support system in a jointed rock mass.

Keywords

Rock excavation;Support system;Earth pressure;Joint set;Rock type;Joint condition

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