Flip the cone upside down and the concrete spreads exactly the same distance. It just takes nearly twice as long to get there. The slump flow test uses the same Abrams cone as the century-old slump test. Three hundred millimetres tall, two hundred across the wide end, one hundred across the narrow end. For self-compacting concrete the cone is filled in a single lift with no rodding, lifted vertically, and the mix allowed to spread into a pancake under its own weight. The mean of two perpendicular diameters is the slump flow. ASTM C1611 permits two orientations, and this is where it becomes interesting. - Procedure A stands the cone upright, wide end down. Filling the 100 mm opening needs a funnel, and a technician must stand on the foot pieces to stop the mix escaping - Procedure B inverts the cone, narrow end down. Concrete is poured straight into the 200 mm opening. One person, no funnel, no foot tabs Inter-laboratory work at the Nordic Innovation Centre found no meaningful diffe...