DIRECT SHEAR APPARATUS (HAND OPERATED):

AS PER IS: 2720 (Part - Vlll), ASTM D- 3080.

Introduction:

• Information of Shear values plays an important role in the design of sub-structures in determining bearing capacity of soils, design of retaining walls, instability calculation of earth slopes etc.
• Various Shear Apparatus are available and Direct Shear Apparatus is one of them.
• In Direct Shear test specimen contained in a box is subjected to a constant normal load and increasing horizontal load is applied to the upper section of the specimen.
• Shear force and load are directly measured.
• For determination of the direct shear strength of soils on specimen size 60 mm x 60mm x 25 mm.

General Description and Specifications:

• Loading Unit : with V strips on which shear box housing rests, load yoke with direct and lever system for applying normal load to the capacity of 8 kg/cm sq, fixture for proving ring, bracket for holding dial gauge, and manually operated lead screw for application of shear stress. Complicated counter balancing arrangement has been dispensed with and the unit is provided with pre-calibrated loading yoke.

• Shear Box Assembly for Square Specimen: Comprising Direct Shear box in two halves for a square specimen size 60 x 60 x 25 mm one pair of plain gripper plates, one pair of perforated gripper plates, one pair of porous stones, one top loading pad. Shear box housing: Accommodates the Direct Shear Box assembly.

• Shear Box Housing: Suitable to accommodates shear box assembly complete with two ball roller strips.

• Specimen Cutter: For cutting specimen size 60 x 60 x 25 mm obtained from field or from larger specimen.

• Set of Weights: To give normal stress of 3 kg/cm sq on specimen through lever as follows:
• 0.05 kg/cm² - 4 Nos.
• 0.1 kg/cm²   - 1 No.
• 0.2 kg/cm²   - 1 No.
• 0.5 kg/cm²   - 3 Nos.
• 1.0 kg/cm²   - 1 No.

• Proving Ring: High sensitivity compression Made of special alloy steel equipped proving Ring capacity 200 kg (2 KN) with dial gauge 0.01 mm x 25 mm.

Optional extras:

• Additional set of weights to give a normal stress of 5 kg/cm2.
• Soil Sampler for 60 mm x 60 mm specimen and test from pad of 50.
• Spares : Porous stone for 60 mm x 60 mm size sample available in pairs.