A method of preparing a concrete composition for downhole injection includes utilizing a controller to control a process including circulating process water in a process water supply loop for a predetermined period while monitoring and controlling the temperature and flow rate of the process water, circulating aqueous-based air entrainment solution in an aqueous-based air entrainment solution supply loop for the predetermined period and controlling the flow rate of the aqueous-based air entrainment solution and after the predetermined period of time in which the flow of process water and aqueous-based air entrainment solution have stabilized, simultaneously actuating valves to divert and mix the process water, the aqueous-based air entrainment solution and compressed air to produce an air-entrained foam and mixing the foam with a concrete composition to be deployed downhole.

Some aspects of what is described here relate to analyzing a well cement slurry. In some aspects, a well cement slurry is mixed in a mixer under a plurality of conditions. The plurality of conditions correspond to a plurality of distinct Reynolds number values for the well cement slurry in the mixer. Power number values associated with mixing the well cement slurry in the mixer under the plurality of conditions are identified. Each power number value is based on an amount of energy used to mix the well cement slurry under a respective one of the plurality of conditions. Values for parameters of a functional relationship between power number and Reynolds number are identified based on the power number values and the Reynolds number values for the plurality of conditions.

A quality control system of the invention allows controlling, image analysis and continuous visual monitoring of aggregates and sand processing, and physical properties and workability of fresh concrete and concrete mixes, which are manufactured from the aggregates and sand, and then transported to construction sites and used there for construction purposes. The system of the invention comprises visual monitoring devices (100), stationary or mobile, installed or remotely used at quarries, concrete plants, in concrete trucks and at the construction sites. The method for continuous visual monitoring of the aggregates, sand and concrete is based on image or video processing and analysis of the aggregates and sand, fresh concrete, concrete mixes or precast concrete, the concrete slump levels, segregation and bleeding, homogeneity of the mixture and consistency.

Techniques for additive construction of structures and production of additive construction materials are described, including a 3D printing assembly including a container configured to store a material, a mixer configured to mix the material to provide an extrudable mix including cementitious material, and a dispenser configured to receive the flowable mix from the mixer and to provide the flowable mix under one or more controlled parameters to form a structure, and a controller configured to receive a value associated with a material property parameter of the material, to generate a mixture by inputting the value into a machine learning algorithm, the mixture being generated using, by the controller, another value associated with a control parameter configured to control operation of the 3D printing assembly, and using the 3D printing assembly to print a structure using the mixture.

A mixer vehicle includes a mixer drum, a first acceleration sensor, a second acceleration sensor, and a controller. The first acceleration sensor is configured to produce first acceleration signals and the second acceleration sensor is configured to measure accelerations within the mixer drum to produce second acceleration signals. The controller is configured to receive the first acceleration signals from the first acceleration sensor and second acceleration signals from the second acceleration sensor. The controller is further configured to determine a presence of material within the mixer drum based on the first acceleration signals and the second acceleration signals. The controller is further configured to determine one or more properties of the material within the mixer drum based on the first acceleration signals and the second acceleration signals.

Some aspects of what is described here relate to analyzing a well cement slurry. In some aspects, a well cement slurry is mixed in a mixer under a plurality of conditions. The plurality of conditions correspond to a plurality of distinct Reynolds number values for the well cement slurry in the mixer. Power number values associated with mixing the well cement slurry in the mixer under the plurality of conditions are identified. Each power number value is based on an amount of energy used to mix the well cement slurry under a respective one of the plurality of conditions. Values for parameters of a functional relationship between power number and Reynolds number are identified based on the power number values and the Reynolds number values for the plurality of conditions.

A concrete mixer vehicle includes a mixer drum, a chute, and a controller. The mixer drum has an inner volume configured to hold a mixture for transportation and placement. The chute is configured to receive mixture exiting the mixer drum and direct the mixture. The controller is configured to receive a selected mode of operation of the mixer drum and the chute. The selected mode of operation is selected from a set of multiple modes of operation of the mixer drum and the chute. The controller is configured to adjust an operation of at least one of the mixer drum or the chute to cause at least one of the mixer drum or the chute to operate according to the selected mode of operation.

A mixer vehicle includes a mixer drum, a first acceleration sensor, a second acceleration sensor, and a controller. The first acceleration sensor is configured to produce first acceleration signals and the second acceleration sensor is configured to measure accelerations within the mixer drum to produce second acceleration signals. The controller is configured to receive the first acceleration signals from the first acceleration sensor and second acceleration signals from the second acceleration sensor. The controller is further configured to determine a presence of material within the mixer drum based on the first acceleration signals and the second acceleration signals. The controller is further configured to determine one or more properties of the material within the mixer drum based on the first acceleration signals and the second acceleration signals.

Sounds are generated by an aerial vehicle during operation. For example, the motors and propellers of an aerial vehicle generate sounds during operation. Disclosed are systems, methods, and apparatus for actively adjusting the shape of a propeller blade of an aerial vehicle during operation of the aerial vehicle. For example, the propeller blade may have one or more joints that adjust to alter the shape of the propeller blade. The altered shape of the propeller blade causes the propeller to generate different frequencies of sound as it rotates. By altering multiple propeller blades of the aerial vehicle, the different sounds generated by the different propeller blades may effectively cancel or reduce the total sound generated by the aerial vehicle, and/or alter the total frequency generated.

The present invention provides a method and system for detecting hardened concrete buildup in a mixer drum which is substantially devoid of plastic concrete. An exemplary method involves monitoring the hydraulic pressure required to rotate the drum through at least two successive rotations at constant speed, using a hydraulic pressure sensor on hydraulic charge side, discharge side, or preferably both sides of the hydraulic motor which turns the mixer drum; and detecting when the pressure/time data curve indicates eccentric behavior of the mixer drum, whereby an alarm or other indication is provided to confirm that the hardened concrete buildup in the truck is not acceptable. The buildup detection method and system of the present invention does not require the use of an automated slump monitoring system, but can be implemented in combination with such systems with favorable results and advantages.