Method of dynamic probing of soils and device for its realisation

FIELD: construction.

SUBSTANCE: method of dynamic probing of soils, in which a rod with a probe is submerged into soil by means of periodical shocks, and during each shock they determine parameters of soil impact to sensors of the measurement system, providing for amplification of signals from sensors, their analog-digital conversion, registration and transfer of data, including dependence of probe movement on time and dependence of head resistance variation on time, into the outer block of data processing with the help of the appropriate software, as a result of which they determine physical and mechanical characteristics of soil. The probe is submerged into soil with the help of a hydraulic hammer machine. The hydraulic hammer machine after introduction of the rod with the probe is lifted, and the rod is extracted with the probe after introduction of the probe to the specified depth by means of hydraulic hoists. In addition, to measure displacement of the probe during shock, they measure the outer sensor of movement with an autonomous recorder. Data registration is carried out with the help of a recording block adapted for direct connection with the outer block of data processing (computer). To determine soil characteristics, they perform mathematical modelling and solve an inverse problem based on experimental dependences of probe movement on time, variation of head resistance on time and other data.

EFFECT: increased manufacturability, efficiency and depth of research.

 

The invention relates to the field of construction, namely the study of the physical-mechanical characteristics of the soil dynamic probing.

Known installation ESM-15M (research Institute of transport construction, the Guide dynamic contact sensing of soils, Moscow, 1983), in which the probe tip and the rod is embedded in the soil through the shock of the cable mechanism. The load is lifted by the winch, and then reset. Readings are taken visually. This method has low productivity and small depth research. Realizing the way the device has a large weight and dimensions.

Also known hydroshock machine according to patent No. 2229559 and No. 2252299, which has high performance and is intended for introduction into the soil probe. Weight hydroshock machines about 75 kg, while setting ESM-15M has a mass of 1100 kg, However, this machine cannot implement the method, providing high performance and depth of research.

From patent application No. 2008125936 known selected as the closest analogue is the way to studies of soil dynamic sensing, including immersion of the probe into the ground by hammering and the determination of physical-mechanical characteristics of soil sensors for exposure parameters g is the flying boot to the sensors, characterized in that the characterization is produced by the application of torque, equipped with sensors Mendoza electronic measuring system, by receiving signals from sensors, amplification, conversion-to-digital Converter analog-to-digital converters (ADCS), reception, processing and transmission of the block of information management. However, it does not provide high performance and depth of research. A device that implements the method and selected as the closest analogue that contains a rod probe with a conical tip, a percussion device, a means of extracting the probe from the soil, placed in the tip of the probe measurement system, including sensors, amplifiers, ADC, registration unit, configured to send data to an external processing unit, supplied with software. The device has the same disadvantages as it is implemented in its way.

The invention is directed to solving the problems of improving manufacturability, performance, and depth of research.

The invention consists in that in the method of dynamic sensing of soils, in which the immersed rod probe into the soil by periodic shock and during each blow determine the parameters of the impact of soil PA sensors of the measuring system, respecive amplification of signals from sensors, their analog-to-digital conversion, recording and transmission of data, including the dependence of the displacement of the probe from time to time, and the dependence of the drag from time to time, the external data processing unit using the appropriate software, the result of which determine the physical and mechanical characteristics of the soil, we offer a probe submerged in the ground with hydroshock machines, lifting hydroshock machines after the implementation of the rod with the probe, and removing the rod from the probe after the introduction of the probe to a predetermined depth to produce the platforms, in addition to displacement measuring probe at impact to use an external displacement transducer with Autonomous Registrar registration data to produce by using the recording unit, adapted for direct connection with an external data processing unit (computer), and to determine the characteristics of the soil to produce mathematical modeling and to solve the inverse problem on the basis of the experimental dependencies of moving the probe from time to time, change the drag from time to time, and other data.

The invention also lies in the fact that the device for dynamic sensing of soil containing rod probe with a conical tip, impact device, extractor AOR is Yes from the soil, posted in tip of the probe measurement system, including sensors, amplifiers, ADC, registration unit, configured to send data to an external processing unit, supplied with software, offers a percussion device to perform as hydroshock machines, means of extraction of the probe from the soil to perform on the basis of the platforms so that they provide lift hydroshock machines after the implementation of the rod with the probe, and removing the rod from the probe after the introduction of the probe to a predetermined depth, in addition to measuring the movement of the probe when hitting enter in an external displacement transducer with independent Registrar, the registration unit adapted for direct connection with external the data processing unit (computer), the external data processing unit to provide software for the characterization of soil by mathematical modeling and solution of the inverse problem on the basis of the experimental dependences of the displacement of the probe from the time trend of drag from time to time, and other data.

The use of miniature electronic recording unit to record and store information when probing placed in the tip of the probe, provides high performance and manufacturability issledovanija more accurate measurement of the displacement of the probe when the kick is an external displacement transducer with a standalone recorder. Characteristics of soils are determined not by the tables, because the tables in the SP-11 - 105 - 97 are given only for sandy soil, and according to dynamic sensing and mathematical modeling.

Figure 1 shows a block diagram of a device implementing the method of dynamic sensing of soils. Figure 2 shows the block diagram of the tip of the probe. Figure 3 shows graphs of the variation of the force of drag from a single shot in different types of soil. Figure 4 shows the graphs of moving the probe from one blow in different types of soil.

Device for dynamic sensing of soils, shown in figures 1,2 can be set, for example, on the vehicle (figures not shown). It contains a percussion device (immersion probe), is made on the basis hydroshock machines. Tip 1 probe includes accelerometer 2 and the load cell 3, which through appropriate linkages 4,5 are connected with the inputs of the high-speed recording unit - logger 6. In the handpiece 1 of the probe also has connected to the logger 6 communication 7 unit 8 power. Hydroshock machine 10 is installed on the rod 11 and is driven by a not shown in the figures oil station with valve-regulator 9. At the beginning of the dive hydroshock machine 10 is the upper starting position, then in the process of immersion on what's allowed in the extreme lower position. Translation hydroshock machines 10 from the lower position to the original upper position is performed by means of the platforms 13. The platforms 13 are also used to extract the rod 11 after the end of the dive. The sensor 12 is used to move the Desk graphics probe.

Dynamic probing tip 1 probe is introduced into the ground by hammering. At impact there faster. Acceleration recorded with an accelerometer 2. Load cell 3 installed inside the hollow cylinder resting on the tapered portion of the tip of the probe 1, fix the force of drag cone during its introduction into the soil. Figure 3 shows graphs of the variation of the force of drag in different types of soil. Logger 6 is intended for reception, recording and storing data received from the accelerometer 2 and the load cell 3. For this logger 6 is not shown in the figures LCP (analog-to-digital Converter) and a memory block. Prointegrirowany time acceleration, which are recorded by the accelerometer 2, we can determine the rate of introduction of the probe. Further, if re-integrate acceleration, that is now the speed, then eventually learn to move the probe over time. Graphics move the probe over time in different types of soils shown PA 3.

To offer the technology to determine the construction and properties of soils used mathematical modeling of the interaction of the probe with ground-based nonlinear soil mechanics and software. Modeling of the stress-strain state of soil, which is used in our technology, complicated by the fact that it is necessary to solve the inverse problem. When solving the inverse problem as the source of information used experimental data. We have experimental graphs of moving the probe over time, figure 3, the graphs of the variation of drag with time, figure 2, and other data (the frequency of oscillation of the probe, the force of the blow, shock acceleration, and others). Through mathematical modeling, we construct a similar virtual graphics. Further, by optimization calculations we come up virtual graphics to experimental to a predetermined degree of accuracy. When we succeed, then we say that the soil has the same values of parameters and construction of properties, as in the virtual model. The software package is designed so that allows us to describe the motion of the tip of the probe in a soil medium with obtaining charts, graphs similar to the real dynamic sensing is shown in figures 3, 4. By solving the optimization problem we can achieve the maximum approximation estimated graphs for real. At their coincidence with acceptable accuracy conclude that the soil parameters match the values in the computational model.

1. The way dynamic sensing of soils, in which the om is dipped into the bar with the probe into the soil by periodic shock and during each blow determine the parameters of the impact of soil on the sensors of the measuring system, providing amplification of signals from sensors, analog-to-digital conversion, recording and transmission of data, including the dependence of the displacement of the probe from the time and the dependence of the drag from time to time, the external data processing unit using the appropriate software, the result of which determine the physical and mechanical characteristics of the soil, characterized in that the probe is dipped into the ground with hydroshock machines, lifting hydroshock machines after the implementation of the rod with the probe, and removing the rod from the probe after the introduction of the probe to a predetermined depth produced by the platforms, in addition to measuring the movement of the probe when hitting the use of an external displacement transducer with offline Registrar registration data is produced using a recording unit, adapted for direct connection with an external data processing unit (computer), and to determine the characteristics of the soil produce mathematical modelling and solve the inverse problem on the basis of the experimental dependencies of moving the probe from time to time, change the drag from time to time, and other data.

2. Device for dynamic sensing of soil containing rod probe with a conical tip, impact device, extractor probe and the ground, posted in tip of the probe measurement system, including sensors, amplifiers, ADC, registration unit, configured to send data to an external processing unit, supplied with software, wherein the impact device is made in the form of a hydroshock machines, means of extraction of the probe from the soil is made on the basis of the platforms so that they provide lift hydroshock machines after the implementation of the rod with the probe, and removing the rod from the probe after the introduction of the probe to a predetermined depth, in addition to measuring the movement of the probe when the shot put external displacement transducer with independent Registrar, the registration unit is adapted for direct connection with an external data processing unit (computer), the external data processing unit is supplied with software for determining the characteristics of the ground by mathematical modeling and solution of the inverse problem on the basis of the experimental dependencies of moving the probe from time to time, change the drag from time to time, and other data.



 

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EFFECT: reduced ground investigation time.

4 dwg

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