California Bearing Ratio

The California Bearing Ratio Test (CBR Test) is a penetration test developed by California State Highway Department (U.S.A.) for evaluating the bearing capacity of sub grade soil for design of flexible pavement.

Tests are carried out on natural or compacted soils in water soaked or un-soaked conditions and the results so obtained are compared with the curves of standard test to have an idea of the soil strength of the sub grade soil.

Laboratory CBR Apparatus meets the essential requirements of IS:2720 (Part XVI) with the mould as per of IS:9669. The field CBR Apparatus meets the requirements of IS:2720 (Part XXXI).

Laboratory CBR Apparatus, Hand Operated

HS 20.05

The apparatus consists of :-

  • Hand Operated Load Frame, capacity 5000 kg (50 KN).
  • CBR Mould 150 mm base plate and collar inner dia x 175 mm high.
  • Cutting collar.
  • Perforated swell plate.
  • Spacer disc.
  • Metallic ring made of mild steel.
  • Metal tripod aluminium.
  • Penetration Piston Assembly.
  • Proving ring 10 kN capacity.
  • One surcharge weight, 2.5 kg, annular.
  • One surcharge weight, 2.5 kg slotted.
  • Dial gauge 0.01 x 25mm

Laboratory CBR Apparatus (Motorised)

HS 20.10

Same as HS20.05 except that the unit is supplied with motorized load frame having single rate of strain of 1.25 mm/m. Suitable for a power supply of 220v, 50 Hz, single phase. This Unit is inclusive of all accessories as mentioned HS20.02 S.No. (ii)+(xii)

Field CBR Test Apparatus

HS 20.15

The equipment consists of the following:

  • Loading jack screw type, capacity 10,000 kg (100 kN).
  • Penetration piston assembly.
  • Set of 7 extension spacers with connectors.
  • Dial Gauge support of @1.500m length.
  • Surcharge weights slotted. – 5 kg weight 215-250 mm dia – Two. – 10kg weight 215-250mm diatwo.
  • Surcharge weight, annular, 5 kg, 250 mm dia – one.
  • Proving ring 100 kN
  • Dial gauge 0. 01 x 25mm

North Dakota Cone

HS 20.30

It consists of :-

  • A shaft with a steel cone of angle 15 – 30º attached to one side of the shaft and sliding vertically in a frame. The movement of the shaft relative to frame is measured by means of a rod graduated in mm.
  • A set of weights, (5 kg each, 7 Nos.)

Swell Pressure Test Apparatus

HS 20.40

Test is performed as per IS:2720 (Part-XII). For measuring the swelling pressure of partially saturated soils when subjected to saturation.

The apparatus consists of :-

  • Load frame, 500kg (5kN) capacity, hand operated.
  • Mould with100 mm internal dia x 127.3 mm high, 1000 cm³ volume.
  • Proving Ring 250 kg (2.5 kN) capacity with load transfer bar and steel ball.
  • Soaking tank 25 cm dia x 20 cm high.
  • Dial gauge 0. 01 x 25mm

Portable Swelling Pressure and Heave Evaluating Apparatus

HS 20.45

The unit is light weight and portable, which can be easily carried to the site.
The equipment comprises of :-

  • Light weight aluminium alloy base with pillar provided with brackets to hold proving ring for estimation of swell pressure and dial gauge to record the soil heave.
  • Ring assembly, complete with saturation tank, bottom porous stone, consolidation ring 60 mm dia, acrylic loading pad with a central hemispherical recession to hold the steel ball in position for uniform vertical loading of the test specimen.
  • Dial gauge 0.01 mm x 25 mm travel.
  • Proving Ring 25 kgf with calibration chart.
  • Spacer block for preparation of test specimen, rammer, scoop.