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Testing method

GENERAL REQUIREMENTS FOR CONCRETE VIBRATORS, SCREED BOARD TYPE

GENERAL REQUIREMENTS FOR CONCRETE VIBRATORS, SCREED BOARD TYPE SCOPE This standard lays down the requirements for materials, sizes, construction, assembly and performance of screed board concrete vibrators, screed board vibrators operated by pneumatic power are not covered in this standard. TERMINOLOGY For the purpose of this standard, the following definitions shall apply. Amplitude of Vibration - Maximum displacement of a vibrating. body from its mean position during vibration. It is usually expressed as half of its total displacement. Eccentric Shaft ( Rotor ) - The rotating shaft of the vibrating unit designed to produce the required frequency and amplitude of vibration. Anchor - The arrangement provided to give a support to the screed board when desired. Frequency of Vibration - Number of complete cycles of vibrations per minute. Screed Board ( Tamping Beam or Vibrating Beam ) - The beam to which the vibrating unit ...
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PILE FOUNDATIONS

DESCRIPTION This work shall consist of construction of all types of piles for structures in accordance with the details shown on the drawings and conforming to the requirements of these Specifications or as directed by the Engineer. The construction of pile foundations requires a careful choice of the piling system depending on subsoil conditions and loading characteristics and type of structure. The permissible limits of total and differential settlements, unsupported length of pile under scour, impact/entanglement of floating bodies and any other special requirements of project, are also equally important criteria for selection of the piling system. The method of installing the piles, including details of the equipment shall be submitted by the Contractor and got approved from the Engineer before commencement of work. The work shall be carried out as per IS:2911 except as modified herein. SUBSURFACE INVESTIGATIONS The complete subsurface inve...
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Location: Hojai, Assam 782435, India
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TEN PERCENT FINES VALUE.

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TEN PERCENT FINES VALUE. ( BS : 812 – PART – 111 ) INTRODUCTION: The ‘Ten percent fines’ value is a measure of resistance of the aggregates to the crushing. Object : To determine the ten percent value of aggregates by crushing machine apparatus. Apparatus : a) Steel cylinder with open ends, and internal diameter 152mm, square base plate, plunger having a piston of diameter 150mm, 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. b) Cylindrical measure having internal diameter of 115mm and height 180mm. c) Steel tamping rod with one rounded end, having a diameter of 16mm and length 450 to 600mm. d) Balance of capacity 3 kg with accuracy up to 1gm. e) Compressive testing machine capable of applying load of 40 tonnes, at a uniform rate of loading of 4 tonnes per minute. Procedure : The aggregate passing 14mm IS sieve and retained on 10mm IS sieve is ...
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STRIPPING VALUE OF AGGREGATES.

STRIPPING VALUE OF AGGREGATES. (IS: 6241 – 1959) INTRODUCTION: Bitumen and tar adhere well to all normal types of aggregates provided they are dry and are not exceptionally dusty. Largely the viscosity of the binder controls the process of binding. When the viscosity of the binder is high, coating of aggregates by the binder is slower. In the absence of water there is practically no adhesion problem in bituminous road construction. Two problems are observed due to the presence of water. First, if aggregate is wet and cool it is normally not possible to coat with a bituminous binder. This problem can be dealt with by removing the water film on aggregate by drying, and by increasing the mixing temperature. Second problem is stripping of coated binder from the aggregate due to the presence of water. This problem of stripping is experienced only with bituminous mixtures, which are permeable to water. Object : To determine the stripping value of aggregates by static i...
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SPECIFIC GRAVITY TEST.

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SPECIFIC GRAVITY TEST. ( IS : 1202 – 1978 ) Object : To determine the specific gravity of the bitumen by specific gravity bottle. Apparatus : a) Pycnometer / specific gravity bottle – 50 ml capacity. b) Balance – sensitivity 0.1mg. Procedure : The specific gravity bottle is cleaned, dried and weighed along with the stopper. It is filled with fresh distilled water, stopper placed and the same is kept in water container for at least half an hour at temperature 27 0 C +/- 1 0 C. The bottle is then removed and cleaned from outside. The specific gravity bottle containing distilled water is now weighed. The bituminous material is heated to a pouring temperature and is poured in the above empty bottle taking all the precautions that it is clean and dry before filling sample materials. The material is filled up to the half taking care to prevent entry of air bubbles. To permit an escape of air bubbles, the sample bottle is allowed to stand for half an hou...
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SPECIFIC GRAVITY TEST FOR SOILS.

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SPECIFIC GRAVITY TEST FOR SOILS.   ( IS : 2720 – PART – 3 ) Object : To determine the specific gravity of soil fraction passing 4.75 mm sieve by density bottle.   Apparatus : 1) Density bottle of 50ml / 100ml capacity. 2) Balance sensitive to 0.01g. 3) Wash bottle with deaired distilled water 4) Vacuum source Procedure : To clean and dry the density bottle, wash it thoroughly with distilled water and allow it to drain. Weigh the empty cleaned bottle (W1) accurate to 0.01g with its stopper. Take about 10 to 20 grams of oven dried soil sample; find the weight (W2) of the bottle and the soil, with the stopper. Put about 10ml of deaired distilled water in the bottle, so that the soil is fully soaked. Leave it for a period of 2 to 10 hours. Add more distilled water so that the bottle is about half full. Remove the entrapped air by subjecting the contents to a partial vacuum, then find out the weight (W3). Clean the bottle thoroughly and fill it ...
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