ASTM C31/C31M:21 pdf free download – Standard Practice for Making and Curing Concrete Test Specimens in the Field.
Select a scamp of the size described in 5.7, While placing the concrete in the mold, move the scoup around rite perimeter of the mold opening to ensure an even distribution of the concrete with minimal segregation. Each layer of concrete shall be consolidated as requiresi. lit placing the final layer. add an amount of concrete that will till the mold after consolidatam.
9.2.1 Seff-Coenwltikr.rdng (austere—If casting cylinders of self-consolidating concrete. use the mold tilling procedures in lratace Cll5lteUl75XM instead of the procedure in 9.2. Attn tilling the mold, finish the cylinders in accordance with 9.5. without further consolid.aam.
9.3 Costing Amino—Select the proper ramping rod from 5.4 and Table I or proper vibrator 1mm 5.5. Detennine the method of consolidation from. unless another method Ii specified. If the method of consolidation is ralding. determine the molding requirements horn Table 4. If the method of consolidation Is vibration, determine the molding raluweinents from Table 5. Determine the number of roddings per layer. one Ice each 14 cm 12 in. of the top unlace area of he beans. Select a placement tool as described in 3.7. UsIng the scamp or shovel, place the concrete in the mold to the height required for each layer. Place the concrete no that it is anilorinly drstrihuied within each layer with minimal segregation. Each layer shall he consolidated as required. In placing the Ilnal layer. add an aimaunt of concrete that will fill the mold alter consolidation.
9.3.1 Self-lf casting beams of self-cow.olid;iting concrete, use the mold filling procedures in Practice Cl 75Ill75hM Instead of the procedure in 9.3.Atln filling the mold, finish the beams in accordance with 9.5. without further consolidation.
9,4 Conuifidmnmmm—llme methods of consolidation for this practice are mdding or internal vibration.
9.4.1 Roskfing—litace the concrete en the tnold in else required number of Layers of agiwosimately equal volume. Rod each layer uniformly over he cnu.s section with the rounded end of the rat using the required number of strokes, Rod the bottom layer throughout its depth. In rodding this Layer.
II. Transportation of Specimens to Laboratotry
11.1 Priw to cure and specimens as required in Section 10. Specimens shall not Lw traisponcd until a least II h altec linal set (Sec Note 131. During transporting. pnitect the spectnlens watt suitable tusluonang ntaten.aI to present damage (mm inning. During cold weather, pmtect the sjtintens (mm Erecting with suitable insulaLion material. loss ikinng transxinat.on by wrapping the simens in plastic, wet burlap. by surmunding them with wet swat, or tight lilting plastic capem on plastic molds. Transçwwiadon time shall not emated 4 h.