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ASTM C1568-08(R2020) pdf free download

ASTM C1568-08(R2020) pdf free download.Standard Test Method for Wind Resistance of Concrete and Clay Roof Tiles (Mechanical Uplift Resistance Method)
4. Significance and Use
4.1 The method of attachment of roof tiles to the roof deck, or support structure, is one factor in the resistance of concrete and clay roof tiles to the action of wind. Several systems of attachment, and even combinations of systems, are used in the application of tile to a roof. The mechanical uplift resistance of the tile, when applied to the roof by any attachment system approved by, and in accordance with, the manufacturer’s instructions, is a primary factor in the tile’s resistance to the action of wind. This test method determines the mechanical uplift resistance that is related to resistance to the uplift forces acting as a result of wind. Natural wind conditions differ with respect to intensity, duration, and turbulence; these conditions are beyond the means of this test method to simulate.
5. Apparatus
5.1 A test apparatus shown in Fig. 1 shall be used to test the mechanical uplift resistance of roof tiles. The triangulated framework and loading bar shall be constructed oftubular steel of sufficient strength to remain rigid when loads of up to 500 lbf are applied to the test tile. The frame shall be fixed to the floor to prevent movement of the frame and to provide a solid reference plane for deflection measurements. The joints of the frame shall be rigid, however, the loading bar rotates about the frame to facilitate the loading of the test tile. The other end of the loading bar is attached to a hydraulic jack, or similarly controllable mechanical device, which allows the load to be applied gradually and to be maintained at any desired load while deflections are being measured The load is applied to the tile through a load transfer device (steel bolt with chain linkage) and is measured by a load cell capable of operating at up to 500 lbf. The roofframing used for the specimens shall be either fixed to the floor, anchored to the triangulated framework, or weighted to prevent the roofframing from being lifted during the test. Deflections are measured by dial gages firmly fixed to a reference plane so that as the tile is loaded and the tile or test frame distorts, the reference position remains static. A dial gage plunger is placed on top of the tile nose in a central position to measure the mechanical uplift of the tile. Additional dial gages are required depending on the method of tile attachment: (a) in mechanically fastened systems, a dial gage at the fastener in the bead of the tile to measure withdrawal of the fastener; (b) when a clip is used, a dial gage at the clip to measure deflection and permanent set of the clip; and (c) when a barrel tile is used, a dial gage at the roll of the tile to measure the deflection of the roll due to the rotation of this type of tile.
6. Procedure
6.1 Drill the test tile and install the steel-bolt load-transfer device into to the tile as follows: 6.1.1 Drill a hole along the centerline of the exposed width of the tile at 0.76 times the tile length from the head of the tile using a 1 ⁄ 4 in. (6 mm) non-percussion, cutting carbide bit. Discard any tile that, after drilling, exhibits spalling or chip- ping around the hole in excess of 1 ⁄ 4 in. (6 mm). Install a 4 in. (100 mm) long, 1 ⁄ 4 in. (6 mm) diameter steel bolt with a 1 in. (25 mm) diameter steel washer under the tile through the hole. It is not prohibited to shape the washer to match the contour of the underside of the tile. It is also not prohibited to omit the washer.

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