Shear strength of gravel and rockfill measured in triaxial and prismatic wedge shear tests

TOSUN H., Mirata T., MOLLAMAHMUTOĞLU M. , Çolakoglu N.

Electronic Journal of Geotechnical Engineering, cilt.4, 1999 (Diğer Kurumların Hakemli Dergileri) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 4
  • Basım Tarihi: 1999
  • Dergi Adı: Electronic Journal of Geotechnical Engineering


The prismatic wedge shear test (priswest) is a relatively new technique for measuring the shear strength of gravels and gravelly clays using a portable frame and a right prismatic box (test mould) consisting of two identical halves separated by 5 mm to 12 mm high spacers which, when removed, leave the plane of shear, measuring 300 mm × 300 mm at the start of shear and inclined at an angle usually between 30° and 45° to the main load P, free for testing. P is applied through two grooved plates with steel balls in between; a relatively small lateral load has a similar effect as the cell pressure in the triaxial test in increasing the average principal stress range in the test. It has previously been demonstrated for 5 mm to 10 mm gravel that the priswest gives results consistent with those of drained triaxial tests on 100-mm dia. specimens. A more recent comparison has been made for clayey gravel with particles finer than 38 mm. Presented in this paper are comparisons between the peak strength measured in priswests on several gravels and crushed rock with particles finer than 38 mm and that measured in drained triaxial tests on 191-mm dia. samples. The agreement between the results of the two types of test is remarkable, the minor differences being generally explicable by the fact that the priswest is more nearly a plane strain type of test.