Flow Table Apparatus (As per IS 9103: 1999) The flow table apparatus shall be constructed in accordance with Fig. 1A and 1B. Flow table top shall be constructed from a flat metal plate of minimum thickness 1.5 mm. The top shall have a plan area of 700 mm × 700 mm and a flatness of within 1.5 mm. The centre of the table shall be scribed with a cross, the lines of which run parallel to and out to the edges of the plate, and with a central circle 200 mm in diameter. The under surface of the plate shall be reinforced in order to prevent distortion of the flat surface. The front of the flow table top shall be provided with a lifting handle as shown in Fig. 1. The total mass of the flow table top shall be 16 ± 1 kg.
The flow table top shall be hinged to a base frame using externally mounted hinges in such a way that no aggregate can become trapped easily between the hinges or hinged surfaces. The front of the base frame shall extend a minimum 120 mm beyond the flow table top in order to provide a top board. An upper stop similar to that shown in Fig. 1A shall be provided on each side of the table so that the lower front edge of the table can only be lifted 40 ± 1 mm.The lower front edge of the flow table top shall be provided with two hard rigid stops which transfer the load to the base frame. The base frame shall be so constructed that this load is then transferred directly to the surface on which the flow table is placed so that there is minimal attendance for the flow table top to bounce when allowed to fall.
The mould is made of a metal readily not attacked by cement paste or liable to rust and of minimum thickness 1.5 mm. The interior of the mould shall be smooth and free from projections, such as protruding rivets, and shall be free from dents. The mould shall be in the form of a hollow frustum of a cone having the internal dimensions as shown in Fig. 2. The base and the top shall be open and parallel to each other and at right angles to the axis of the cone. The mould shall be provided with two metal foot pieces at the bottom and two handles above them.
C-1.4.2 Tamping Bar
The tamping bar shall be made of a suitable hardwood and having dimensions as shown in Fig. 3.
C-2.1 The sample of freshly mixed concrete shall be obtained in accordance with the provisions given in IS 1199.
C-3 PROCEDUREThe flow table shall be level and properly supported. Before commencing the test, the table-top and inner surface of the mould shall be wiped with a damp cloth. The slump cone is placed centrally on the table and to be held in position by standing on the two foot pieces. The slump cone is to be filled with concrete in two equal layers, each layer tamped lightly 10 times with the wooden tamping bar. After filling the mould, the concrete is to be struck off flush with the upper edge of the slump cone and the free area of the table-top cleaned off. Half a minute after striking off the concrete, the cone shall be slowly raised vertically by the handles. After this, the table-top raised by the handle and allowed to fall 15 times in 15 s. The concrete spreads itself out. The diameter of the concrete spread shall then be measured in two directions, parallel to the table edges. The arithmetic mean of the two diameters shall be the measurement of flow in millimeters