Hall current sensor application in cement mixing piles

Renyunye Ankerui Electric Co.
, Ltd.
Shanghai Jiading 201801 [Abstract] Cement mixing pile is a method used for soft foundation treatment, it uses cement as the main agent of curing agent, uses a mixing pile machine to spray cement into the soil and fully mix, so that cement and soil have a series of physicochemical reactions, so that soft soil hardens and improves the strength
of the foundation.

The hydration activity of cement slurry directly affects the strength of cement soil, monitors the electromagnetic field strength of cement slurry magnetization through Hall current sensor, adjusts the electromagnetic field strength in real time and maintains stability through the magnetic field control device, so as to achieve the purpose of improving the activity of cement slurry and increasing the uniformity of
cement and soil stirring.

【Keywords】Hall current sensor; Cement mixing; Introduction to Electromagnetic Field Strength In the 1970s, China began to use cement mixing piles to strengthen soft soil foundations, which has a history of
more than 40 years.

It is through a special mixer, the soft soil and cement (curing agent) forced mixing, and the use of a series of physical and chemical reactions generated between cement and soft soil, the soil consolidation, the formation of a solid, water stability and a certain strength of the soil pile, the process is mainly used for soft soil foundation treatment
.

Due to the convenient operation and cheap price of cement mixing piles, they were favored by the construction in the early stage of promotion, but in the implementation process, there was a problem that the strength of cement and soil was not high, and the reason was that the cement slurry and soil hydration reaction were insufficient, which affected the treatment
of soft soil foundations.

First, the application of Hall current sensor in cement mixing pile composition of cement mixing pile includes roller, coil, magnet, grouting machine, power source, magnetic field control device and cement mixing pile tool
.

The cement mixing pile magnetizes the cement slurry through the electromagnetic field to enhance the hydration of the cement slurry, which is divided into two stages: First, the water particles move laterally under the action of the magnetic field composed of magnets, and the water is easy to react with the cement particles under the action of the magnetic field during the regular movement; Second, after the magnetic field composed of the coil is activated by the longitudinal movement of the water, the water is easy to complete the hydration reaction with some cement particles that have not undergone hydration reaction
under the action of the magnetic field.

As shown in Figure 1, it is a flow chart
of cement mixing pile magnetized cement slurry.

Hall current sensors are used in magnetic field control devices, Hall current sensors monitor the electromagnetic field strength in real time and convert their detection results into corresponding analog signals
.

The microcontroller samples the analog signal, and compares the sampling value with the set electromagnetic field strength input value, if it is not equal, the current is adjusted by the magnetic field control device to change the electromagnetic field intensity, until the sampling value is equal to the set electromagnetic field strength input value, so as to complete the real-time adjustment of the electromagnetic field strength and maintain stability, so as to achieve the purpose of improving the cement slurry and increasing the uniformity of
cement and soil stirring.

Figure 1 Cement stirred pile magnetized cement slurry flow diagram two, Hall current sensor 1.
Overview Hall current sensor is mainly suitable for AC, DC, pulse and other complex signals isolation conversion, through the Hall effect principle so that the transformed signal can be directly collected by the single-chip microcomputer AD, DSP, PLC, secondary instruments and other acquisition devices, widely used in current monitoring, battery applications, inverter power supply and solar power management system, DC screen and DC motor drive, plating, Welding applications, frequency converters, UPS servo control and other systems of current signal acquisition and feedback control, with fast response time, wide current measurement range and high precision, strong overload capacity, good linearity, strong anti-interference ability and other advantages
.

2.
Technical parameters three, the conclusion of the cement mixing pile equipped with the Ankerui Hall current sensor has been officially put into operation at a construction site, cement mixing pile through the Hall current sensor for real-time monitoring and adjustment of the electromagnetic field strength, so as to maintain the electromagnetic field strength stability, to achieve the purpose of improving the cement slurry, increase the uniformity of the mixing of cement and soil, to ensure the quality of the project to provide strong support
.

About author:Ren Yunye, male, electronic information engineering, mainly engaged in the research and development
of power sensors.