ASTM C1435/C1435M-20 PDF Download

The ASTM C1435/C1435M-20 standard provides guidelines for molding stiff to very dry consistency concrete mixtures used in roller-compacted concrete construction. This practice is specifically designed for testing roller-compacted concrete but can also be applicable to other cementitious materials such as coarse-grained soil-cement.

The standard emphasizes the use of a vibrating hammer equipped with a shaft and circular plate to consolidate and mold cylindrical test specimens. This method is used as an alternative to traditional rodding or internal vibration techniques, which are ineffective for consolidating concrete with this level of consistency.

The molded cylindrical specimens produced according to this practice can be used for various tests, including testing compressive or tensile strength of concrete as per Test Methods C39/C39M and C496/C496M, respectively. These specimens can also be used to determine the density of fresh concrete. However, it is noted that for extremely dry mixtures, the density of the specimens may not accurately reflect the in-place density of roller-compacted concrete, due to potential voids at the bottom of the lifts in the field.

The standard also includes references to additional documents, such as ACI 207.5R and ACI 211.3, for further information on roller-compacted concrete consistency. It is important to consider the mass of the apparatus and the force applied by the operator, as these factors can significantly affect the density of the specimens made from these mixtures.