• The Journal of Engineering Geology
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• v.13 no.3
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• pp.321-334
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• 2003

This study is aimed at the effective measurement plan of discontinuity orientation on rock mass. The discontinuity orientation is expressed as three methods. strike/dip. dipdirection/dip (a three digit number / a two digit number) and right hand rule. Generally, strike/dip is measured with clinometer. and dipdirection/dip with silva compass(type15). A sign of strike/dip. discontinuity orientation is used to geological survey. and dipdirection/dip to engineering. Dipdirection/dip converted by strike/dip measured with clinometer is useful on the statistical analysis of a lot of data. To measure the azimuth of the dip with clinometer and to change strike/dip to dipdirection/dip may have potential errors in each person. The newly designed apparatus, clinometer equipped by a rotational azimuth plate and an arrow to measuring strike and dipdirection, has been developed to measure effectively the discontinuity orientation with two method (strike/dip and dipdirection/dip). The measuring method of discontinuity orientation with clinometer having newly designed apparatus is effective one for accurate measurement of strike as well as dipdirection which is degrees counted clockwise from true north. Used by clinometer with newly designed apparatus, concurrent measuring strike/dip and dipdirecton/dip of discontinuity is possible. In application to measuring discontinuity orientation on rock slope, it has been recognized that the newly designed method, unambiguously, led to drop measuring errors comparing with existing measuring apparatuses. Therefore, it is considered that measuring method of discontinuity orientation (strike/dip and dipdirecton/dip) by the newly designed apparatus is useful to one in geological engineering investigation of road design, and to unskilled investigator.

• The Journal of Engineering Geology
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• v.8 no.2
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• pp.131-143
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• 1998

The study area, Beulgok-myon Nonsan-goon Chungcheongnan-do is consist of Changri slate(Och, okcheon system), lithic tuff(Kslt, kyoungsang system), granite (Kqb, kyoungsang system) and quartz porphyry(Kgf, kyoungsang system). More than 3000 joints were measured and classified by direction. Main dipdirection/dips of Kqb are 228~257/73~88, 010~150/70~85, Och are 134~164/40~90, 214~249/55~89, Kslt are 291~332/75~82, 235~241/73~71. But Kgf are not appeared distinct directions of joint. In field, p-wave velocities(Vp) are measured on the bed rock. Vp of Kgf are $5000m(240^{\circ})~2380(360^{\circ})m/s$, Kqb are $3846(210^{\circ})~1408(150^{\circ})m/s$, Kslt are $5000(360^{\circ})~2323(150^{\circ})m/s$ and Och are $6657(180^{\circ})~2000(030^{\circ})m/s$. Also P-wave velocities on specimen are measured. It is slightely higher than it's measured on the bed rock. For engineering properties of rock, we measured Poisson's ratio, rigidity, Young's modulus and bulk modulus by dynamic method.