Method and system for detecting and regulating workability of concrete in concrete mixer truck

A system for detecting workability of concrete in a concrete mixer truck, comprising:

• a rheological shear device arranged inside a drum of a concrete mixer truck, configured to directly convert resistance experienced by a rheological shear rod exposed to concrete flowing during rotation of the drum into a pressure signal;
• wherein the rheological shear device comprises the rheological shear rod and a pressure sensor;
• wherein the rheological shear rod inserts into concrete inside the drum and is used to directly detect a resistance experienced by the concrete during the rotation of the drum when the concrete is shear flowed, and the resistance is converted into a pressure experienced by the pressure sensor through a law of lever;
• wherein the pressure experienced by the pressure sensor is used to characterize a pressure exerted on the drum when the concrete flows at different times during the rotation of the drum of the concrete mixer truck during transportation;
• wherein the pressure sensor is arranged on bottom of the drum and penetrates the drum;
• wherein the rheological shear rod is immersed into the concrete;
• and wherein the rheological shear rod is a sheet-like rod, and a length and a cross-sectional shape of the sheet-like rod are adjusted according to resistance experienced by the sheet-like rod during shear flow of different concretes;
• a rheological parameter calculation module, configured to obtain a relationship between a rotation speed of the drum and a resistance experienced by the rheological shear rod at different times based on the pressure signal;
• wherein an intercept of a straight line of the relationship represents a yield value, and a slope of the straight line of the relationship represents a plastic viscosity;
• and
• a workability real-time detection module, configured to reflect a workability by using the yield value and the plastic viscosity, and obtain a time-varying relationship of the workability during concrete transportation, thereby achieving a real-time detection of the workability.