Wide speed range concrete monitoring calibration

Abstract

A method and system for concrete monitoring calibration using truck-mounted mixer drum jump speed data selectively assimilated from previous deliveries. In preferred embodiments, the invention surprisingly employs data obtained using different concrete mix designs, as well as jump speed data obtained from high speed mixing after the trucks arrive at the construction delivery site and before pouring the concrete into place at the site. The method involves measuring energy (E) in terms of pressure or force associated with mixing the concrete ('E1') at a first drum speed (“V1”) and measuring energy (E2) after a speed jump of +/−2.5 RPM or more to a second drum speed (V2). Slump is calculated using low speed energy/speed/slump curve data, or pre-stored equation wherein slump(S) is derived as a function of slope of the line defined by E1, V1 and E2, V2 and intercept of the plotted relationship (at E axis where V is zero). The E/V/S relationship in the provided concrete is compared to at least two pre-stored data curves across drum speed ranges of 0.5 RPM-6 RPM and 6 RPM-20 RPM, to ascertain whether the provided concrete matches any of the stored curve data (i.e., previous concrete E/V/S profiles); and either activating the monitoring system for all drum speed ranges where a match is confirmed or allowing the monitoring system to calculate slump only at low drum speeds (below 6 RPM) and alerting a system user or operator that the system is only active for low speed monitoring.