Material & Soil Testing Instruments

• Mould made from gun metal/brass, 150mm internal diameter x 175mm high with perforated base plate and extension coller 50mm high
• Perforated plate made of gue matal/brass 148mm dia with adjustable stem and lock nut and a metal tripod for dial gauge
• Cutting collar
• Rammer 2. 6kg weight with drop of 310mm
• Rammer 4. 89kg with drop of 450mm

The shear strength of soil is the maximum resistance that it can offer to any stress on it. Every building or structure which is founded in or the earth imposes loads on the soil that support the foundation.The stresses set up in the soil causes deformations of the soil. One stress failure is caused by slipping of soil particles one on another, which may lead to the sliding of one body of soil relative to the surrounding mass.The process is known as shear failure and occurs when shear stresses set up in the soil mass exceeds the maximum shear resistance, which the soil can offer i.e. its shear strength.

Direct shear apparatus:- The soil specimen is placed in a circular box divide into two halves. The specimen is subjected to a constant load while an increasing horizontal force is applied to one of the sections of the shear box. This force causes the specimen to shear along the juncture between the box sections. The shear force and the normal load, both are measured directly. By testing a number of specimens under normal loads a relationship between the normal stress and maximum shear stress can be developed, which is a straight line in most of the cases. The angle which the resulting straight line makes with the horizontal axis and the intersect which the straight line makes with the vertical axis are reported as the angle of shear resistance (angle of internal friction) and cohesion intercept respectively.

The information about these shear characteristics provided by the direct shear test is of importance in the design of sub structure, in determining bearing capacity of soils, in stability calculations of earth slopes, design of retaining walls etc.

Abrasion testing machine (los angels), digital

Loss Angels Abrasion Value Apparatus : The machine consists of a hollow cylinder mounted horizontally on a study frame on ball bearings. There is an opening which can be closed with a dust tight cover to facilitate charging and discharging the drum with the material under test.

A detachable shelf which extends throughout the inside length of the drum which catches the abrasive charge and does not allow it to fall on the cover. The drum is rotated by an electric motor through a heavy reduction gear at a speed of 30-32 rpm. A revolution counter is fitted to the frame. A tray is supplied for collection of the material at the end of the test. Complete with abrasive charge consisting of a set of twelve hardened steel balls, approximately 48 mm diameter. Suitable for operation on 440 volts, 3 phase, 50 cycles, AC supply.

Direct shear apparatus (single speed –hand operated)

The apparatus comprises of the following.

Loading unit :

Supplied with load yoke with direct and lever system for applying load. Normal stress capacity 8 kg/sq. cm. Load is applied either directly or through a counter balanced detachable lever. Provision is made for the load to be applied either through a steel ball recessed in the loading pad or direct through a boss on the pre calibrated loading yoke. The loading unit is provided with V strips and roller strips for frictionless movement of shear box housing.

Shear box assembly :

Comprising direct shear box in two halves for a square specimen size 60 x 60 x 25mm one pair of plain gripper plates, One pair of perforated gripper plates, one pair of porous stones, one top of loading pad.

Shear box housing:

Accommodates the direct shear box assembly. Complete with two ball roller strips. Specimen cutter : for cutting 60 x 60 x 25mm. Specimen form larger samples. Set of weights to give a normal stress of 3kg/sa.cm. Through larger as following : -

To give kg/cm. 0.05,Qty. 4 nos.
To give kg/cm. 0.1,Qty. 1 no.
To give kg/cm. 0.2,Qty. 1 no.
To give kg/cm. 0.5,Qty. 3 nos.
To give kg/cm. 1.0,Qty. 1 no.
Complete set as above but without proving ring. Net weight 140 kg.

Ductility Testing Machine :-

BIS : 1208. For determining of asphalt, cut bitumen and blown type bitumen.

It consists of a bath thermostatically controlled with inlet and outlet taps. Fixed and movable brackets are so positioned that specimen is submerged in water throughout. The rates of pull of 50 mm/min. and 10 mm/min, air incorporated. A clutch arrangement is made to stop the movement of the movable bracket when repture of the specimen is noticed. Suitable for operation on 230 volts, 50 cycles, single phase, A.C. supply. Complete with three moulds and plates supplied mounted on the apparatus but without thermometer.

Vicat Needle Apparatus

BIS : 4031 5513. For determining the normal consistency and the setting times of cements and the setting times of Class A lines. Complete with one each of mould, glass plate, Initial needle, final needle and consistency plunger. Scale reading upto 40 mm.

fitted with a dashpot.

Speedy Moisture Meter:

ASTM D 4944

Specifications:

The unit consist of a pressure vessel with clamp for sealing cap, capacity is 20gms, rubber sealing gasket, pressure gauge calibrated in percentage moisture content 0-25% x 25% on the wet weight basis, on electronic balance for weighing sample, a scoop for measuring carbide reagent, a bottle of reagent, one cleaning brush and a set of 4 steel balls for through mixing. Complete in highly polished wooden carrying case with handle

Marshal stability test apparatus:

Motorized ASTM: D 1559- T –62.

 With proving ring Cap 50KN and dial gauge 0.01 x 25mm

 Generally the test is applicable to hot mix designs using bitumen and aggregates upto a maximum size of 25mm. In this method, the resistance to plastic deformation of cylindrical specimen of bituminous mixture is measured when the same is loaded at periphery at 5 cm per min. This test procedure is used in designing and evaluating bituminous paving mixes. The test procedure is extensively used in routine test programmers for paving jobs. There are two major features of the Marshall method of designing mixes namely, a) density – voids analysis b) Stability – flow tests.

The Marshall stability of mix is defined as a maximum load carried by a compacted specimen at a standard test temperature of 60ºC. The flow value is deformation the Marshall test specimen under goes during the loading upto the maximum load, 0.25 mm units. In this test and attempt is made to determine optimum binder content for the type of aggregate mix and traffic intensity.

The apparatus consists of: 1) A loading unit motorized, capacity 5000kgf with two telescopic pillars and an adjustable cross head. Limit switches are fitted inside to control upward or downward movement of the pillars. On-off reversing switch and indicator lamps are on the front side while a hand wheel to manually move the pillars is on the right. The load frame has fixed speed of 5.80cm per minute. Operated on 230 Volts A.C.

Standard accessories:

Marshal Mould 100 mm dia  -- 6 Nos

Marshal Rammer  ---- 2 Nos

Pedestal   ---- 1 Nos

Braking head ---- 1 Nos

Blaine’s Air Permeability Apparatus :-

BIS : 5516. It is used for determination of fineness of cements, pozzolanss and other powdery material in terms of specific surface, which is expressed as total surface area in sq. cm. per gram of material under test.

The apparatus comprises the followings :-
a. Standard Permeability cell made of brass, 12.5 mm. inside dia with one perforated metal disc and one plunger.
b. A U – tube glass manometer with rubber coupling for permeability cell, mounted on a wooden stand.
c. Latex rubber tubing, 30 cm. long.
d. 250 ml. Dibutylphthalate liquid

CTM (3000KN)

Compression (Cube) Testing Machine Electrically  Cum-Hand Operated

Pumping Unit. The double glunger pump is a motorized unit, which is housed in an elegant cabinet, is driven by three phase, electric motor 440 volts, A.C. supply (NB : Machine can be supplied for operation 220/230 volts. 50 cycles phase A.C. supply also-as may be indicated in the order.) The pumping unit is a separate unit connected to the jack by means of a steel connecting tube. A junction box is suitabily fixed to connect the motor to the main through the push bottom starter.

The pumping unit is fitted with 20 cm dia dial pressure gauge (Hydraulic) with 200 division-in tones or in KN< (as per the rated capacity of the machine) A maximum red pointer is provided to facilitate taking reading after failure of specimens. The pressure gauge is fixed at an angle for easy readability. The machine is fitted with a hand wheel control, which enables the rate of application of load to be varied. The machine is equipped with facilities for hand pumping in case of power failure. The electrical pumping unit is fixed with a micro switch to off the motor automatically as the load on the machine approaches at rated capacity. Relays are also incorporated in the pumping unit so that in case of break down of power supply the motor will stop and would not restart unless starting switch is operated.