GB692471A - A new or improved method and apparatus for testing the ground - Google Patents

Abstract

692,471. Testing physical qualities of material. CADLING, L. O. T. Aug. 25, 1948 [Sept. 5, 1947], No. 22395/48. Class 106 (ii). Apparatus for testing soil comprises a core rotatably mounted in a tube and having at one end a bit formed with radial vanes, means secured to the upper end of the core connected elastically to a rotatable member co-axial with and adjacent to the upper end of the tube and means for indicating angular displacement of the core resulting from rotation of the rotatable member. A rod 3, built up from sections, is protected by a tube 4, also in sections, which are joined by collars 6, and carries at its lower end a bit 1 having vanes 2. The rod 3 and tube 4 are driven into the ground to the depth at which a test is to be made and then the bit 1 is projected to the position shown into soil undisturbed by the tube 4. A torque is then applied to the rod 3 by a handle 13, rotatable upon a collar 9 secured to the tube 4 and connected by springs 14 to a bar 8 secured to the rod 3. When the bar 8 commences to move due to shearing of the soil, the handle 13 is held stationary and the time for the bar 8 to move through a predetermined arc is observed. This is stated to be a measure of the property of the soil under test. A calibrated disc 10 mounted on the collar 9 enables the angular displacement of the rod 3 and bit 1 to be observed. The rod 1 is guided by a plug 5 in the tube 4 and the rod 3 is guided by internal projections 7 of the collars 6 and by a similar projection 12 of the collar 9. The tube 4 may be extended so as to protect the bit as it is driven into the ground. The Specification as open to inspection under Sect. 91, states that electrical strain gauges may be secured to the vanes of the bit. This subject-matter does not appear in the Specification as accepted.