M. K. Instruments

Khokhra, ahmedabad, Gujarat

It is used for the determination of soundness by expansion method of ordinary and rapid hardening Portland cement, low heat Portland cement and class 'A' Limes.

Specification :It consists of a small split cylinder forming a mould. On either side of the split cylinder. Two parallel indicating arms with pointed ends are attached. Supplied complete with two glass plates and a lead weight.

The design of concrete mix is aimed at maximum durability for the conditions where it is to be used. Ability to resist the flow of water through is one of the important durability characteristics. The permeability is determined on cement mortar and concrete specimens, either cast in the laboratory or obtained by cutting out cores from existing structures. The Permeability test is carried out as per the standard, IS:3085 and US Bureau of Reclamation, specifications.

High Pressure Permeability Test can be conducted on different size specimens using different cells. Each cell is made of steel and provided with a top plate and funnel at the bottom having gasket seals held in position through bolts and nuts. The concrete specimens are sealed in the cell to prevent any leakage along the side walls. The permeated water is collected in glass bottles attached at the bottom. Each test stall has its own control system, operating pressure gauges and valves. The pressure sight glass tubes are fully protected by a shatter proof panel The multi-unit per-meameters are so designed that all tests can be performed at the same time, using either the same head or varying head pressure, as each test stall is provided with its own pressure regulator and control. The control instruments are mounted on a sturdy welded structural stand. All multi-units are provided with end pressure gauges. Each unit is provided with chamber pressure gauges of 0-20 kg/cm2 and test pressure gauges of 0-15 kg/cm2. Pressures are applied using any available pressure line at the site or a compressor.

• Concrete Permeability Tester for specimen 100mm dia x 100mm height with 3 cells
• Concrete Permeability Tester for specimen 100mm dia x 100mm height with 1 cell
• Concrete Permeability Tester for specimen 150mm dia x 150mm height with 3 cells
• Concrete Permeability Tester for specimen 150mm dia x 150mm height with 1 cell
• Concrete Permeability Tester for specimen 300mm dia x 300mm height with 3 cells
• Concrete Permeability Tester for specimen 300mm dia x 300mm height with 1 cell

This equipment is required to determine the heat of hydration of cement as expressed in calories per gram.

The Euipment comprises of the following :

• A wide mounted double walled vacuum flask with a stop cock 38 mm & a insulating container for the flask
• A Beckman thermometer (Range 5 C )held tightly by the cock stopper in such a way as to avoid accidental contact with the stirrer blade & the reading lens. To facilitate the easy removal the cock stopper is in two halves.
• A constant speed stirrer (double bladed propeller type)extended to within 38 mm from the bottom of the flask.
• A funnel (Gooch type)with a stem of 6 mm inner dia & a body approx 25 mm long and 25 mm dia is fitted to the cock stopper for introducing the sample

All the above to combine to form the calorimeter for the determination of heat of hydration of cement. Suitable To Operate on 230 V A.C. 50 Hz.

The procedure, as recommended in various standards, is for determining the quantity of water required to produce a cement paste of standard consistency. The standard consistency is attained when the 10 mm plunger of the apparatus penetrates the material to a pre-determined depth under free-fall. A new sample is prepared and tested with initial and final needles in accordance with the procedure described in various specifications. Vicat Apparatus consists of a frame bearing a movable rod with a cap at top and a Vicat mould in the form of the frustum of a cone, (80+5)/70 + 5mm dia at the base, (70mm+5mm) /60 mm at the top and 40 mm high, and with a glass base plate of minimum 2.5 mm thickness with various models of Vicat apparatus as per standard specifications. Two models of Vicat Apparatus are offered

• Vicat Apparatus, IS: 5513 The apparatus includes one each of: Vicat Mould, Glass Base Plate, Initial Needle (in Plastic Case), Final Needle (in Plastic Case) Consistency Plunger (in Plastic Case)
• Vicat Apparatus with Dashpot, IS: 5513This apparatus includes Dashpot to facilitate the gentle lowering of the moveable rod.

For water proofing of concrete admixture and special water proof cements are used. Water proofing of these compounds, is established by measuring permeability of standard mortar. Specimen with or without such water proofing compounds. Permeability apparatus in used to determine permeability to water of cement mortar specimens with or without water proofing compound.

Specification :

The pressure chamber is fitted with a pressure regulator which helps in regulating the pressure from 0-7kg/sq. cm. The regulator has two pressure gauges, one for indicating the pressure in the chamber (0-10.5kg/sq.cm.) The pressure chamber is connected to the cells with pressure hoses and with couplings. This pressure chamber is fitted with valve. Pressure is applied to the pressure chamber with help of a foot pump and rubber hose which are supplied with the instrument.

• Three Cell Model mounted on a stand.
• Six Cell Model mounted on a stand.
• Twelve Cell Model mounted on a stand.

Accessories : Specimen casting mould C.I. with base plate 100mm dia x 50mm height.

Carries upto 7 sieves of 150mm or 200mm diameter. The shaker is driven by a H.P. Motor through a reduction gear immersed in oil. The sieve table does not rotate but is inclined from the vertical axis and the direction on inclination charges progressively in clockwise direction. If the stop pin below the table is removed, the shaker can have a rotary motion. In addition to this gyratory motion of the table, there is an upward and downward movement ensuring that each square cm of the sieve is utilized. A pair of rods and a holder are supplied. The holder can be fixed on the top of the upper most sieve, and thus the sieve set in firmly held. Suitable for operation form 230 V, 50 Hz Single Phase A.C. Supply.

Base has cleats on its underside to help dig into the ground surface Positive clamping of slump cone to the base while filling and rodding the concrete A combination swivel carrying handle also doubles as the datum making the conventional and somewhat awkward measuring procedure of using a foot rule and a datum bar, a thing of the past

Supplied complete with base plate, having cleats and swivel handle

This test is considered suitable for cohesive and plastic mixes of concrete containing aggregate smaller than 50 mm.

The slump cone is filled with freshly mixed concrete and is tamped with a tamping bar in three or four layers. The top of the concrete is leveled off with the top of the slump cone, the cone is lifted vertically up and the slump of the sample is immediately measured.`

This is used for determination of in situ dry density of natural or compacted fine grained soil, free from aggregates. A cylindrical cutter is used to extract a sample of the soil with the help of a dolly and rammer. From the weight, density and the moisture, and dry density of the soil is ready calculated. It consists one each of: cylindrical core cutter mode of steel, 127.3mm. Long and 100mm internal diameter. Steel dolly, 25mm high with a lip to enable it to be located on top of the core cutter, rammer with detachable steel rod.

Casagrande method in mechanical form is known as liquid limit method and has been in use for soil mechanics for a number of decades. The liquid limit data of soils is useful to correlate mechanical properties of soil, such as compressibility and lower shear strength. Liquid limit is the water content at which soil passes from zero strength to an infinite strength, hence the true value of liquid limit cannot be determined. For determination purpose liquid limit is that water content at which a part of soil, cut by a groove of standard dimensions, will flow together for a distance of 1.25cm under an impact of 25 blows in a standard liquid limit apparatus. The soil at the water content has some strength which is about 0.17N/cm. sq. (17gms/sq.cm.) . At this water content soil just passes from liquid state to plastic state. It consists on a brass cup held on an adjustable bracket. The cup can be adjusted for a fall of 1 cm and can be raised an dropped on a rubber base of standard hardness by cam action. Complete with one Casagrande grooving tool, one ASTM grooving tool and a height gauge block.

• fitted with a counter to register the number of blows.
• fitted with a motor geared down to give approximately 120 rpm. Suitable for operation on 230 V A.C., Single Phase, 50 Cycles.

A useful tool for workability determination of concrete mixes of very low workability such as those normally used with Concrete, compacted by Vibration. Concrete mix having maximum size of aggregate exceeding 38 mm can be tested for workability. Apparatus is complete with hoppers and receiver assembly.

It consists of two rigid conical hoppers and a cylinder mounted on a rigid metal frame. The lower openings of the hoppers are fitted with hinged trapdoors having a quick release catches. A circular metal plate is provided to cover the top of the cylinder. Supplied complete with one plaster's trowel and one tamping rod, 16mm dia x 600mm long, both ends rounded.

This apparatus is used to determine Softening point of Bitumen. It is that temperature at which a sample of bituminous material loaded by a 9.5mm dia steel ball, drops a specified distance when heated under specified conditions.

Specification :

The apparatus consists of steel bracket with a sliding plate support. That support has two holes of 10mm dia on which a ring and ball guide can be kept. A central hole on this plate is for inserting thermometer. Supplied with a glass beaker approximate 600ml, high and a hand stirrer and 2 Nos. 9.5mm dia steel balls

RING & BALL APPARATUS (ELECTRICALLY OPERATED)

Electrical heating, with a Heater and Energy Regulator, Suitable for operation on 230 V, 50Hz, Single Phase, A.C. supply. Each unit is supplied with bath of heat resistant glass and the following * Tapered Rings, 2 Nos.* Ball Centering Guide, 2 Nos.* Steel Ball, of 9.5mm dia, 2 Nos.* Ring Holder, 1 No.* Electric Heater (Hot Plate), 1 No.

For making standard rectangular specimens of 40 x 40 x 160mm. of Portland and pozzolana cement mortar for determining the transverse strength.

The jolting apparatus consists of a rectangular table rigidly connected by two support arms to a spindle at a horizontal distance of 800 mm from the centre of the table. There is a projecting lug with a plane face on the upper face of the table beneath which is a stop with a rounded upper surface. The table can be raised and allowed to fall freely on the stop by a cam which is connected to a motor and gearbox through a V-belt an pulleys. The cam rotates at a rate of 60 Rev/Min. A stroke counter fitted with micro-switch is provided which stops the machine after 60 Jolts. Locating pins are provided for mounting the mould compartments on the table. The mould surmounted by the hopper can be clamped rigidly to the table. Supplied complete with mould and hopper. Suitable for operation on 230 Volts, Single Phase, A.C. Supply. A Digital Preset Counter can be supplied at an extra cost.

Soil compaction is a fundamental requirement for the construction of earth fill for dams, reservoirs, canal embankments, highways, railways and runways. The relationship between soil moisture content and compacted dry density is very useful for deciding construction specifications and quality control of compacted earth fill. While designing an earth or earth retaining structure, the strength and deformation behaviour of soil is evaluated by testing soil specimen compacted to the density as would be achieved during construction. The construction quality control is essentially to check the density of compacted soil achieved in the field, thereby checking its strength.

Compaction Test Apparatus, Manual IS:2720 (Part 7)-1987, IS:2720 (Part 8)-1990, IS:9198- 1979, IS:10074-1982, BS:1377 Following models of Manual Compaction Test Apparatus.

• Compaction Test Apparatus 100mm ID x 127.3mm height and 1000cc volume for Light Compaction Test As per IS : 2720 Part-VII. Complete with Collar Base Plate and Rammer of 2.6 Kg x 310mm.
• Compaction Test Apparatus 150mm ID x 127.3mm height and 2250cc volume for Heavy Compaction Test As per IS : 2720 Part-VII. Complete with Collar Base Plate and Rammer of 4.89 Kg x 450mm.

Lightweight Aluminium construction Ease of Transportation Unique Telescopic Design Simplifying Field set up Compact, Thereby reducing the amount of storage space needed Benkelman Beam utilizes the technique of using balanced beam in conjunction with a suitable vehicle to measure road flexure The improved Benkelman Beam is a convenient, accurate device for measuring the deflection of flexible pavements under moving wheel loads. Operating on a simple lever arm principle, the unit consists. Supplied with carrying case.

The Aggregate Crushing value provides a relative measure of the resistance of an aggregate to crushing under a gradually applied compressive load. The oven dried and accurately weighed aggregates are subjected to crushing test on compression testing machine and weight of the resultant fines passing the specified IS sieve to the total weight of the sample expressed as a percentage is defined as Aggregate Crushing Value. The apparatus is available in three size 75mm dia for 1/8 to 1/4 size aggregates, 150mm dia for 3/8 to 3/4 aggregate (standard) and 300mm dia for 1 to 2 aggregate.

The Apparatus consists of Test Mould of a 15cm diameter open ended cylinder with base plate, plunger having a piston of diameter 15cm, with a hole provided across the stem of the plunger so that a rod could be inserted for lifting or placing the plunger in the cylinder.

A straight metal tamping rod of circular cross-section 16mm in diameter and 45 to 60 cm long, rounded at one end.

The Direct Shear test is carried out with an apparatus consisting of a square or circular box divided into two halves. The specimen, contained in the box, is subjected to a constant normal load while an increasing horizontal force is applied to one of the sections of the shear box. This force causes a shear failure along the junction between the box sections. The shear force and the normal load are measured directly. The rate of strain is adjusted by the speed of the horizontal force applied. The loading unit has V-strips on which the shear box housing rests. The precalibrated load yoke with direct and lever system for applying normal load of 8 kg/cm2 capacity, fixtures, for proving ring brackets, for holding consolidation and strain dial gauges and lead screw for application of shear stress

The equipment is used for the determination of the relative density of cohesion less free draining soils and meets the essential requirements.

Specification :

The equipment consists one each of: Vibratory table, with a cushioned steel vibrating decks about 75cm x 75cm. It has a frequency of approximately 3600 vibratory table, minute under a 11.5kg load. Amplitude is variable in between 0.65mm in step of 0.05 to 0.25mm, 0.25 to 0.45 mm and 0.45 to 0.65mm. Suitable for operations on 415V, Three Phase supply. Cylindrical metal unit weight mould, 3000ml. Capacity.Guide sleeve with clamp assembly. Surcharges base plate for mould. Handle for surcharge base plate. Surcharge weight. The total weight together with surcharge base plate and handle is equipment to 140 kg. /sq. cm. For mould. Cylindrical metal unit weight mould 15000 ml. capacity. (Total weight together with the above mould & surcharge weight is equivalent to 140 kg./sq. cm) dial gauge 0.01mm x 50mm travel. Extension piece 25mm for dial gauge.

To determine the fineness of cements, pozzolanas and other powdery materials, various international specifications recommend the use of "specific area" method. In the methods described below, air permeability methods are used to determine the specific surface as total surface area in cm/g of material.

Air Permeability Apparatus Blaine Type IS: 5516 IS: 1727, IS: 4031, IS: 4825, ASTM C204, BS: 4359 Part 2, It is a variable flow type air permeability apparatus. The apparatus comprises one each of:

• Permeability Cell, 12.5 mm ID
• U Tube Manometer, mounted on stand
• Perforated Metal Disc
• Plunger
• Rubber Stopper
• Rubber TUbe 20cm long.
• Rubber TUbe 20cm long
• Filter Paper Disc
• Dibutylphthalate Liquid

Used to determine the relevant proportions of clay-like or Plastic fines and dust in granular soils & fine aggregate Consists of:

• Acrylic graduated cylinder (4 nos.)
• Rubber stopper for cylinder (4 nos.)
• Graduated Steel rule 450 mm
• Funnel 100 mm plastic
• Aspirator bottle 5 lts plastic with rubber cock
• Stand for the aspirator bottle with siphon assembly
• Irrgation tube with stop pinch cock & weighted foot assembly

The separation of modifier and bitumen during Hot storage and cold static condition is evaluated by comparing the ring and ball softening point of the top and bottom samples taken from a conditioned, sealed tube of polymer modified bitumen. The conditioning consist of placing a sealed tube of modified bitumen in a vertical position at 163 +/- 5 deg C in an oven and at 6.7 +/- 5 deg C in a freezer for specified time.

Supplied Complete with following:-

• Oven capable of maintaining 163 +/- 5 deg C.
• Freezer, capable of maintaining 6.7 +/- 5 deg C
• Rack, capable of supporting the 3 aluminium tubes in vertical condition in the Oven and freezer.
• Spatula and Hammer.
• 20cm dia fine sieve of 600 micron mesh.
• Glass rod.
• Tweezer.
• Pair of Asbestos Hand Gloves
• Aluminium tubes of 25.4mm dia X 136.7mm length X 1mm thickness - 3 Nos.
• Glass funnel

Permeability Apparatus (Falling Head Permeability)

The apparatus is used for the laboratory determination of permeability of soil using a constant or a variable head. This test is recommended for soils with co-effcient permeability in the range of 0 10-3 to 10-7 cm/sec. The maximum particle size of the soil which can be tested in the mould is 10mm. The equipment comprises one each : Gun metal mould, 100mm I.D. x 127.3mm high x 1000ml Volume. Gun metal mould extension collar, 100mm dia x 60mm high for the above mould. Gun metal drainage base plate with a recess for a porous stone.

Consolidation of clay deposits leads to distress in buildings such as cracks and failures. Consolidation is the reduction of volume of soil due to expulsion of water from its pore space caused by sustained loading. This phenomenon is time dependent. The one-dimensional consolidation test performed on an undisturbed sample of clay is useful for understanding the history of the soil deposit. The test results can be used for calculating the settlement of structures built on clayey soil.

The standard outfit comprises fixed ring type of consolidometer cell for testing specimens 60 mm dia x 20 mm thick, but the unit is so designed that specimens of varying sizes from 50 mm dia to 100 mm dia can also be tested. Besides, the same loading unit can be used with floating ring consolidometer cells, which can be supplied at extra cost. The standard outfit is supplied with a set of weights to give a total pressure of 10 kg/cm2 (besides a seating load of 0.05 kg/cm3 on the specimen), but an additional set of weights are required to reach the full capacity of 20 kg/cm2. The necessary accessories to perform the permeability test of the Varying Head type can also be provided at extra cost. The outfit is also available as three-gang or six-gang in which three/six consolidometers are mounted on a single frame. The consolidation may be measured by the conventional dial gauges or using the transducers and electronic readout unit in Digital Models.