CN112031750A - Device and method for testing radial expansion pressure of static crushing agent in drill hole - Google Patents

Abstract

A device and method for testing radial expansion pressure of a static crushing agent in a drill hole comprises a pressure sensor arranged on a rigid base, a radial expansion pressure testing simulation tube arranged on the top surface of the pressure sensor, a simulation tube axial and radial constraint mechanism and a pressure sensor data acquisition instrument; the test method comprises the following steps: establishing expansion pressure P of crushing agent in radial expansion pressure test simulation pipe by using numerical simulation technology and taking radial expansion pressure test simulation pipe as calculation model_iAnd the pressure F borne by the outer wall of the simulation tube_oThe relationship curve of (1); testing and collecting pressure F on simulation pipe containing crushing agent and arranged on top surface of pressure sensor under axial and radial constraint state by pressure sensor and pressure sensor data collector_oUsing F_oAnd P_iObtaining the radial direction of the crushing agent in the simulated pipe by the relation curveExpansion pressure P_iAnd (3) obtaining the radial expansion pressure of the crushing agent in the drill hole at different hydration times according to the change curve of the hydration reaction time of the crushing agent.

Description

Device and method for testing radial expansion pressure of static crushing agent in borehole

technical field

The invention relates to the field of geotechnical engineering, in particular to a device and method for testing the radial expansion pressure of static crushing agents in boreholes.

Background technique

With the strengthening of people's awareness of environmental protection and the requirements of energy saving and consumption reduction, people's tolerance to vibration, waste rock, toxic and harmful gases, etc. produced by explosive chemical blasting is getting lower and lower. Static crushing agent is widely used in stone mining, building demolition, concrete crushing, rock excavation, deep stress regulation and high slope trimming due to its characteristics of slow expansion and cracking, no sound, no vibration and no harmful gas generation. and other engineering fields.

There are many technical indicators to measure the performance of static crushers, among which expansion pressure is the most important. The accuracy of its measurement is of great significance for the performance evaluation of static crushers, parameter selection and cost control in industrial applications.

At present, the test methods for the expansion pressure of static breakers mainly include the outer tube method, the inner tube method and the pressure sensor method. These three methods all use the resistance strain gauge to measure the strain value of the surface of the object to be measured, and use a certain corresponding relationship to calculate the expansion pressure generated by the expansion agent. Because the hydration reaction of the expansion agent is an exothermic reaction, the temperature generated by the expansion agent has a great influence on the measurement of the resistance strain gauge, resulting in errors in the measurement of the expansion pressure by the resistance strain gauge. To this end, some scholars use temperature compensation sheets or seal the strain gauges with plastic bags instead of plastic bags to eliminate the influence of thermal effects, but these methods have not fundamentally eliminated the influence of the strain gauges.

Based on the above problems, the CN108151937A patent document discloses a testing device and method for the expansion pressure of a static crushing agent, by measuring the deformation on the measuring rod between two limit plates to inversely calculate the radial expansion pressure generated by the expansion agent ; CN109900409A patent document discloses a static crushing agent radial expansion pressure test method, by pasting strain gauges on the metal cylinder table to measure radial strain and tangential strain and bring it into the formula to calculate the radial expansion pressure of static crushing agent . Although these two methods can measure the radial expansion pressure, there are problems such as the complicated bonding process of the strain gages and the high cost caused by the inability to reuse the strain gages.

CN109883591A patent document discloses a static crushing agent expansion pressure measuring device and measuring method, which uses peripheral blocks and top and bottom baffles to form a closed chamber, fills the crushing agent in the closed chamber, and passes the pressure between the peripheral block and the fixed block. The radial expansion pressure of the static breaker is calculated by dividing the dynamometer reading by the cross-sectional area of the enclosed chamber. This method can measure the radial expansion pressure without sticking strain gauges, but it can only be used for the measurement of the expansion pressure of the slurry static crushing agent, not for the roll static crushing agent, and the expansion pressure varies with the depth. A high degree of expansion pressure in place of the expansion pressure generated by the static crushing agent in the entire device will have errors.

Based on the above problems, the CN1441233A patent document discloses a test method and a test device for the expansion pressure of a static cracking agent. The static cracking agent is laterally restrained by a steel mold, so that the static cracking agent can only produce axial expansion and displacement, and then The reading based on the force measuring ring is converted into pressure divided by the action area to calculate the expansion pressure through a linear relationship; CN103323164A patent document discloses a test system for measuring the expansion pressure of a static crushing agent, using a pressure testing machine rigid frame to load a pressure sensor and a moving piston To measure the expansion pressure, after the hydration reaction of the static crushing agent, push the piston and link the pressure box. At this time, the pressure sensor will record the pressure value, and then inversely calculate the expansion pressure of the static crushing agent; CN108444550A patent document discloses a static crushing It is an integrated device for testing the expansion pressure and temperature of the agent, by using the movement of the upper sealing piston in the confinement frame to read the axial expansion pressure during the hydration reaction of the static crushing agent based on the pressure box. Although the static crushing agent expansion pressure testing devices and methods disclosed in these patent documents can avoid the influence of the complex process of pasting resistance strain gauges and thermal effects on the test results, the measured expansion pressures are all axial expansion pressures. In fact, due to the different shaft-diameter ratios of the drilled holes, the expansion pressure of the static crushing agent in the axial and radial directions is not the same. The main role in the production site is the radial expansion pressure of the static crushing agent. The radial expansion pressure as a static crushing agent has a large deviation; and there are problems such as cumbersome test process, high test cost, and low test result accuracy.

To sum up, the existing expansion pressure test methods of static crushing agents have the cumbersome test process, high test cost, low accuracy of test results, can only simply test axial expansion pressure, and can only test slurry static crushing to varying degrees. The technical problems such as the expansion pressure generated by the agent have greatly restricted its application in actual production.

SUMMARY OF THE INVENTION

In order to solve the technical problems existing in the above-mentioned existing static crushing agent expansion pressure testing methods, the present invention provides a static crushing agent radial expansion pressure testing device and method in a borehole.

The radial expansion pressure testing device for static crushing agent in a borehole provided by the present invention includes: a rigid frame, a rigid base, a pressure sensor, a radial expansion pressure test simulation tube, an axial restraint mechanism, a radial restraint mechanism and data from a pressure sensor collector;

The rigid frame is made of high-strength rigid materials, including a base at the bottom, a lower platform at the middle and an upper platform at the upper;

The rigid base is placed on the upper part of the lower platform of the rigid frame;

The pressure sensor is a spoke-type pressure sensor and is placed on the upper part of the rigid base;

The radial expansion pressure test simulation tube is a metal circular tube whose ends can be closed, the inner diameter of which is the same as the hole diameter of the drilled hole (drill holes with different diameters match the radial expansion pressure test simulation tube of different inner diameters), and the length is 100- 300mm, the thickness is 10-100mm; the radial expansion pressure test simulation tube is placed on the top surface of the pressure sensor, and is aligned with the center of the top surface of the pressure sensor;

The axial restraint mechanism consists of an axial screw corresponding to the central axis of the radial expansion pressure test simulation pipe, an axial screw that can advance and retreat through a threaded hole located on the left side of the rigid frame, and an axial screw installed at the outer end of the axial screw. It consists of a lever handle, an axial restraint steel plate welded into one body with the inner end of the axial lead screw, and a top column with the center of the right end of the corresponding radial expansion pressure test simulation tube welded on the right side of the rigid frame; during the test, the axial The screw handle clamps both ends of the radial expansion pressure test simulation tube between the axial restraint steel plate and the top column, and constrains the axial displacement of the radial expansion pressure test simulation tube;

The radial restraint mechanism consists of a radial screw corresponding to the central axis of the radial expansion pressure test simulation pipe, a radial screw that can advance and retreat through a threaded hole located on the upper platform of the rigid frame, and a radial screw installed on the upper end of the radial screw. The radial expansion pressure test simulation tube is clamped between the radially constrained steel plate and the pressure sensor by rotating the radial screw handle during the test. Constrain the radial displacement of the simulated tube in the radial expansion pressure test;

The pressure sensor data acquisition instrument is connected with the pressure sensor through a wire, collects and records the monitoring pressure signal of the pressure sensor in real time, and converts the collected data and the expansion pressure of the static crushing agent in real time through the built-in software.

Further, the radial expansion pressure test simulation tube can be made into a split structure: it is composed of two semicircular segments that are axially bisected and symmetrical to each other, and the two semicircular segments are embedded in each other through a dovetail groove and a dovetail protrusion. It is connected to form a radial expansion pressure test simulation tube, and both ends are sealed by two semicircular segments with a circular cover at one end to form the radial expansion pressure test simulation tube as a whole. The radial expansion pressure test simulation tube adopts this split structure, so that after the test is completed, the expansion agent cured after expansion is taken out by disassembling the radial expansion pressure test simulation tube, so that the radial expansion pressure test simulation tube can be reused.

The method for testing the radial expansion pressure of static crushing agent in a drilling hole using the above-mentioned static crushing agent radial expansion pressure test device in a drilling hole includes the following steps:

Step 1: Establish the relationship curve between the expansion pressure Pi generated by the static crushing agent in the radial expansion pressure test simulation pipe and the pressure F _o on the outer wall of the radial expansion pressure test simulation pipe according to the following method _:

Under the condition that the elastic modulus E and Poisson's ratio u of the material parameters of the radial expansion pressure test simulation pipe are known, the numerical simulation software is used to take the radial expansion pressure test simulation pipe as the calculation model, and the inner wall of the calculation model is subjected to a circumferential uniform pressure. Distribute the stress P _i to simulate the radial expansion pressure generated by the static crushing agent; impose a normal displacement constraint on the contact area between the outer wall of the calculation model and the upper end face of the pressure sensor to simulate the relationship between the pressure sensor and the radial expansion pressure test simulation tube In the constraint area, the monitoring points are arranged at certain distances and the calculation is started. After the calculation, the average stress value of the monitoring points is multiplied by the area of the micro-stress equivalent area existing on the outer wall of the calculation model to calculate the outer wall of the calculation model. The received pressure F _o is used to simulate the pressure measured by the pressure sensor (the radial expansion pressure test simulates the pressure on the outer wall of the pipe); then the corresponding relationship between the pressure F _o measured by the pressure sensor and P _i can be obtained through the calculation software. The radial expansion pressure test simulates the relationship curve between the expansion pressure Pi generated by the static crushing agent in the pipe and the radial expansion pressure test simulates the relationship between the pressure F _o on the outer wall of the _pipe ;

Step 2: Fill the static crushing agent in the radial expansion pressure test simulation tube

Fill the slurry static crushing agent (that is, the static crushing agent after adding water) into the radial expansion pressure test simulation tube (the radial expansion pressure test simulation tube at this time is an integral metal tube); Put it into a flexible sealing bag and then put it into the radial expansion pressure test simulation tube; or immerse the static crushing agent coil with the same inner diameter as the radial expansion pressure test simulation tube into water and put it into the radial expansion pressure test simulation tube;

Step 3: Install the Radial Expansion Pressure Test Dummy Tube

Align the center of the radial expansion pressure test simulation tube filled with static crushing agent with the top surface of the pressure sensor placed on the rigid base and place it on the top surface of the pressure sensor, so that the right end face of the radial expansion pressure test simulation tube and the welding Press the top column on the right side of the rigid frame; manually rotate the axial screw handle to make the axial restraint steel plate press against the left end face of the radial expansion pressure test simulation tube, and clamp the two ends of the radial expansion pressure test simulation tube Hold it between the axial restraint steel plate and the top column to restrain the axial displacement of the radial expansion pressure test simulation pipe; manually rotate the radial screw handle to make the radial restraint steel plate press against the radial expansion pressure test simulation pipe. On the upper outer wall, the radial expansion pressure test simulation tube is clamped between the radial restraint steel plate and the pressure sensor to constrain the radial displacement of the radial expansion pressure test simulation tube;

Step 4: With the expansion of the static crushing agent, the radial expansion pressure is tested by the pressure sensor to test the force F _o on the outer wall of the simulated pipe, and the pressure F _o measured by the pressure sensor is collected by the pressure sensor data acquisition instrument and recorded; use step 1 The obtained relationship curve between the expansion pressure Pi generated by the static crushing agent in the simulated pipe in the expansion pressure test and the pressure F _{o on} the outer wall of the simulated pipe in the radial expansion pressure test can be obtained. The change curve of the expansion pressure _Pi with the hydration reaction time (h) of the static crushing agent, through which the radial expansion pressure of the static crushing agent in the borehole at different hydration reaction times can be obtained.

Beneficial achievements of the present invention:

1. The present invention adopts the radial expansion pressure test established by numerical simulation technology to simulate the relationship between the radial expansion pressure Pi generated by the static crushing agent in the pipe and the radial expansion pressure test to simulate the relationship between the pressure F _o on the outer wall of the _pipe . _{Comparing the relationship curve between the radial expansion pressure Pi of the static crushing agent and the pressure F o on} the outer wall of the tube measured by the outer tube method recognized in the art, the difference between the two is very small, which proves that the method established by the present invention The radial expansion pressure test simulates the relationship between the radial expansion pressure Pi generated by the static crushing agent in the pipe and the radial expansion pressure test simulates the relationship between the pressure F _o on the outer wall of the _pipe as the test standard is accurate and reliable.

2. The present invention simulates the pressure F _o on the outer wall of the pipe by testing the radial expansion pressure test, and uses the established radial expansion pressure test to simulate the radial expansion pressure _Pi generated by the static crushing agent in the pipe and the radial expansion pressure test to simulate the outer wall of the pipe. The relationship curve between the received pressures F _o can be obtained, and the radial expansion pressure test simulates the expansion pressure _Pi generated by the static crushing agent in the pipe. The test method is simple and the test results are accurate.

3. The present invention can effectively avoid the complicated process of pasting the strain gauge in the prior art and the influence of the high temperature generated by the hydration reaction of the static crushing agent on the test result.

4. The present invention overcomes the deviation of using the axial expansion pressure of the static crushing agent as the radial expansion pressure of the static crushing agent required in the production site in the existing expansion pressure measurement method.

5. For boreholes with different diameters, the present invention can simulate the radial expansion pressure test of static crushing agents in boreholes with different diameters by replacing the radial expansion pressure test simulation tubes with different inner diameters and the numerical simulation calculation model.

6. The present invention is applicable to both slurry static breakers and roll static breakers.

Description of drawings

Fig. 1 is the structural representation of the test device of the present invention;

Fig. 2 is the rigid frame schematic diagram in the test device;

3 is a schematic diagram of a radial expansion pressure test simulation tube (half symmetrical to each other) that adopts a split structure in the test device;

4 is a three-dimensional schematic diagram of an axial restraint mechanism (simulated tube) in the test device;

Fig. 5 is the three-dimensional schematic diagram of the radial restraint mechanism (simulated tube) in the test device;

Fig. 6 is a drill hole with a diameter of 50mm as an example, the radial expansion pressure test obtained by the numerical simulation technology in the process of testing the radial expansion pressure generated by the static crushing agent in the drilling hole according to the present invention simulates the diameter generated by the static crushing agent in the pipe The relationship curve between the radial expansion pressure _{Pi and the pressure F o on} the outer wall of the simulated pipe;

Fig. 7 is a radial expansion pressure change curve obtained by using the device of the present invention and the curve of Fig. 6 to simulate the radial expansion pressure generated by the expansion agent in the pipe with the change of the hydration reaction time (h).

Description of symbols in the figure: 1. Rigid frame, 1-1, base, 1-2, lower platform, 1-3, upper platform, 2, rigid base, 3, pressure sensor, 4, radial expansion pressure test simulation tube , 4-1, dovetail groove, 4-2, dovetail convex, 4-3, cover, 5, (simulated tube) axial restraint mechanism, 5-1, axial screw, 5-2, axial screw Handle, 5-3, axial restraint steel plate, 5-4, top column, 6, (simulated tube) radial restraint mechanism, 6-1, radial screw, 6-2, radial screw handle, 6- 3. Radial restraint steel plate, 7. Pressure sensor data acquisition instrument, 8. Static crushing agent.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and embodiments.

In the following example, a 50mm borehole of a mine is blasted with a static crushing agent, and the radial expansion pressure generated by the static crushing agent in the drilling hole is tested by the device and method of the present invention.

Example 1

As shown in FIG. 1, the test device used in this embodiment includes a rigid frame 1, a rigid base 2, a pressure sensor 3, a radial expansion pressure test simulation tube 4, an axial restraint mechanism 5, a radial restraint mechanism 6 and a pressure sensor Data collector 7.

As shown in FIG. 2 , the rigid frame 1 is made of high-strength alloy steel, and includes a base 1-1 at the bottom, a lower platform 1-2 at the middle, and an upper platform 1-3 at the upper.

As shown in FIG. 1 , the rigid base 2 is placed on the upper part of the lower platform. The pressure sensor 3 is a spoke-type pressure sensor, the inner diameter of the top surface is 30 mm, and the outer diameter is 40 mm, and is placed on the upper part of the rigid base.

The radial expansion pressure test simulation tube 4 is made of alloy steel into a split structure (the radial expansion pressure test simulation tube adopts this split structure, which is convenient for the static crushing agent by disassembling the radial expansion pressure test simulation tube after the test is completed. The expanded cured product is taken out, so that the radial expansion pressure test simulation tube can be reused), which is divided into two symmetrical semicircular segments in the axial direction as shown in Figure 3 (only one of them is drawn in Figure 3). A semi-circular segment), two semi-circular segments are embedded with each other through the dovetail groove 4-1 and the dovetail projection 4-2 to form a radial expansion pressure test simulation pipe tube, with two semi-circular tubes at both ends. The circular cover 4-3 at one end of the sheet is sealed to form an overall radial expansion pressure test simulation tube with an inner diameter of 50mm (same as the hole diameter of the drilled hole), a length of 150mm and a thickness of 10mm. The radial expansion pressure test simulates the elastic modulus E=300GPa of the alloy steel material of the pipe, and the Poisson's ratio u=0.37. After the assembled radial expansion pressure test simulation tube is loaded with static crushing agent 8, it is placed on the top surface of the pressure sensor as shown in Figure 1, and is aligned with the center of the top surface of the pressure sensor.

As shown in FIG. 1 and FIG. 4 , the axial restraint mechanism 5 is composed of an axial wire corresponding to the central axis of the expansion pressure test simulation tube, which can advance and retreat through a threaded hole (not shown) located on the left side of the rigid frame. The screw 5-1, the axial screw handle 5-2 installed on the outer end of the axial screw, the axial restraint steel plate 5-3 welded with the inner end of the axial screw and the center welding of the right end of the corresponding expansion pressure test simulation tube The top column on the right side of the rigid frame is composed of 5-4; during the test, the two ends of the axial expansion pressure test simulation tube are clamped between the axial restraint steel plate and the top column by rotating the axial screw handle, Constrain the axial displacement of the simulated tube in the radial expansion pressure test.

As shown in Fig. 1 and Fig. 5, the radial restraint mechanism 6 consists of a radial wire corresponding to the axis center of the expansion pressure test simulation pipe, which can advance and retreat through a threaded hole (not shown) on the upper platform of the rigid frame The screw 6-1, the radial screw handle 6-2 installed on the upper end of the radial screw, and the radial restraint steel plate 6-3 welded into one body with the lower end of the radial screw; during the test, the radial screw is rotated by rotating the screw. The handle clamps the radial expansion pressure test simulation tube between the radial restraint steel plate and the pressure sensor to constrain the radial displacement of the radial expansion pressure test simulation tube;

As shown in Figure 1, the pressure sensor data acquisition instrument 7 and the pressure sensor 3 are connected by wires, and the monitoring pressure signal of the pressure sensor is collected and recorded in real time. Convert in real time.

Use the above test device to test the radial expansion pressure of static crushing agent in the borehole, and proceed as follows:

Step 1: Establish the relationship curve between the expansion pressure Pi generated by the static crushing agent in the radial expansion pressure test simulation pipe and the pressure F _o on the outer wall of the radial expansion pressure test simulation pipe according to the following method _:

Under the condition that the elastic modulus E=300GPa and Poisson’s ratio u=0.37 of the radial expansion pressure test simulation pipe alloy steel material are known, the numerical simulation software FLAC-3D is used to establish a radial expansion pressure test simulation pipe with an inner diameter of 50mm. The calculation model (the mesh is divided into hexahedral elements with a length of less than or equal to 1mm), the circumferential uniform stress Pi of 200MPa, _400MPa , and 60MPa is respectively applied in the calculation model to simulate the expansion pressure generated by the static crushing agent. The normal displacement constraint is imposed in the contact area between the outer wall and the top surface of the pressure sensor (the area 15mm away from the axial center of the outer wall of the calculation model and the length is 5mm) to simulate the interaction between the pressure sensor and the radial expansion pressure test simulation tube. Extrusion, and arrange a monitoring point every 1mm in the constraint area, a total of 12 monitoring points, and then start the calculation, after the calculation is completed, take the mean value of the stress of the 12 monitoring points multiplied by the micro stress equivalent value existing on the outer wall of the model The area area of 20mm ² can be calculated to calculate the pressure F _o on the outer wall of the model to simulate the pressure measured by the pressure sensor (the radial expansion pressure test simulates the pressure on the outer wall of the pipe); then use the calculation software Origin to obtain the diameter shown in Figure 6 The radial expansion pressure test simulates the relationship between the expansion pressure Pi generated by the static crushing agent in the pipe and the radial expansion pressure test to simulate the pressure F _o on the outer wall of the _pipe .

Step 3: Fill the static crushing agent in the radial expansion pressure test simulation tube

Mix water and static breaker at a water-cement ratio of 25%, stir well with a glass rod, and use a funnel to pour the evenly stirred slurry into a flexible sealed bag with a diameter of 50mm and a length of 150mm. During this process, continuous stirring is required. , in order to remove the contained gas, stop grouting after filling the sealed bag, and seal it, then put the sealed flexible sealed bag into one semicircular segment of the split radial expansion pressure test simulation tube, put the other half The circular segment is embedded with each other through the dovetail groove and the dovetail protrusion to form a whole radial expansion pressure test simulation tube with both ends closed, and the flexible sealing bag containing the static crushing agent is wrapped in the radial expansion pressure test simulation tube.

Step 4: Install the Radial Expansion Pressure Test Dummy Tube

Align the center of the radial expansion pressure test simulation tube with the static crushing agent in step 3 and the top surface of the spoked pressure sensor placed on the rigid base on the top surface of the pressure sensor to make the radial expansion pressure test simulation tube The right end face abuts against the top column welded on the right side of the rigid frame; manually rotate the axial screw handle to make the axial restraint steel plate press against the left end face of the radial expansion pressure test simulation pipe, and the radial expansion pressure test simulation pipe The two ends of the shaft are clamped between the axial restraint steel plate and the top column to restrain the axial displacement of the radial expansion pressure test simulation pipe; manually rotate the radial screw handle to make the radial restraint steel plate press against the radial expansion pressure. The upper outer wall of the simulation tube is tested, and the radial expansion pressure test simulation tube is clamped between the radial restraint steel plate and the pressure sensor to constrain the radial displacement of the radial expansion pressure test simulation tube.

Step 5: With the expansion of the static crushing agent, the radial expansion pressure is monitored by the pressure sensor to test the force F _o on the outer wall of the simulated pipe, and the data of the pressure F _o measured by the pressure sensor is collected and recorded by the pressure sensor data acquisition instrument, and obtained by step 1 The radial expansion pressure test simulates the relationship between the expansion pressure Pi generated by the static crushing agent in the pipe and the radial expansion pressure test simulates the relationship between the pressure F _o on the outer wall of the _pipe , and the radial expansion pressure test simulation is shown in Figure 7. The curve of the radial expansion pressure Pi of the static _crushing agent in the pipe with time (h), through which the radial expansion pressure of the static crushing agent in the borehole at different hydration reaction times can be obtained.

Example 2

The test apparatus used in this example is the same as that used in Example 1. It is only step 3 of the radial expansion pressure test method. The static crushing agent is installed in the radial expansion pressure test simulation tube. The static crushing agent coil with a diameter of 50mm and a length of 150mm is immersed in water for 8 minutes and placed in a split radial expansion pressure test. On one semi-circular segment of the simulated tube, the other semi-circular segment is embedded with it through the dovetail groove and the dovetail protrusion to form the whole of the radial expansion pressure test simulation tube with closed ends, wrapping the static crushing agent coil. In the radial expansion pressure test simulated tube. The rest are the same as the test method of Example 1.

Example 3

The difference between the test device used in this example and the test device used in Example 1 is that the split radial expansion pressure test simulation tube is replaced by an integral diameter with a bottom cover at one end and a threaded cover at the other end. The simulation tube (not shown) was tested for the expansion pressure, and the rest of the structure was the same.

The difference between the method of testing the radial expansion pressure of the static crushing agent in the borehole with the test device of this embodiment and the test method of Example 1 is that in step 3, the radial expansion pressure test simulates that when the static crushing agent is filled in the pipe, press 25% water. Ash ratio Mix water and static crushing agent, stir well with a glass rod, directly pour the slurry into the radial expansion pressure test simulation tube with a funnel, and then screw on the cap. The rest are the same as the test method of Example 1.

Claims (3)

1. A static crushing agent radial expansion pressure test device in a borehole is characterized in that: comprising: a rigid frame (1), a rigid base (2), a pressure sensor (3), a radial expansion pressure test simulation tube ( 4), an axial restraint mechanism (5), a radial restraint mechanism (6) and a pressure sensor data acquisition instrument (7); The rigid frame is made of high-strength rigid material, including a base (1-1) at the bottom, a lower platform (1-2) at the middle and an upper platform (1-3) at the upper part; The rigid base is placed on the upper part of the lower platform of the rigid frame; The pressure sensor is a spoke-type pressure sensor and is placed on the upper part of the rigid base; The radial expansion pressure test simulation tube is a metal circular tube whose ends can be closed, its inner diameter is the same as the hole diameter of the drilled hole, the length is 100-300mm, and the thickness is 10-100mm; the radial expansion pressure test simulation tube is placed in the The top surface of the pressure sensor is aligned with the center of the top surface of the pressure sensor; The axial restraint mechanism consists of an axial lead screw (5-1) that can advance and retreat through a threaded hole located on the left side of the rigid frame corresponding to the central axis of the radial expansion pressure test simulation pipe, and is installed on the axial lead screw The axial screw handle (5-2) at the outer end, the axial restraint steel plate (5-3) welded into one body with the inner end of the axial screw, and the center of the right end of the corresponding radial expansion pressure test simulation tube are welded to the rigid frame The top column (5-4) on the right side is composed of; during the test, the two ends of the radial expansion pressure test simulation tube are clamped between the axial restraint steel plate and the top column by rotating the axial screw handle. Expansion pressure test simulates the axial displacement of the tube for restraint; The radial restraint mechanism consists of a radial screw (6-1) that can advance and retreat through a threaded hole located on the upper platform of the rigid frame corresponding to the central axis of the radial expansion pressure test simulation pipe, and is installed on the radial screw. The radial screw handle (6-2) at the upper end and the radial restraint steel plate (6-3) welded into one body with the lower end of the radial screw are composed of; during the test, the radial expansion pressure is tested by rotating the radial screw handle The two ends of the simulated tube are clamped between the radial restraint steel plate and the pressure sensor to constrain the radial displacement of the simulated tube for the radial expansion pressure test; The pressure sensor data acquisition instrument is connected with the pressure sensor through a wire, collects and records the monitoring pressure signal of the pressure sensor in real time, and converts the collected data and the expansion pressure of the static crushing agent in real time through the built-in software. 2 . The radial expansion pressure test device for static crushing agent in a borehole according to claim 1 , wherein the radial expansion pressure test simulation pipe can be made into a split structure: it is divided into symmetrical parts by axial direction. 3 . It is composed of two semicircular segments, which are embedded with each other through the dovetail groove (4-1) and the dovetail projection (4-2) to form a radial expansion pressure test simulation tube. One end of the circular segment is sealed with a circular cover (4-3) to form the whole of the radial expansion pressure test simulation tube. 3. the method for testing the radial expansion pressure of static crushing agent in the borehole using the static crushing agent radial expansion pressure test device in the borehole according to claim 1, is characterized in that, comprises the following steps: Step 1: Establish the relationship curve between the expansion pressure Pi generated by the static crushing agent in the radial expansion pressure test simulation pipe and the pressure F _o on the outer wall of the radial expansion pressure test simulation pipe according to the following method _: Under the condition that the elastic modulus E and Poisson's ratio u of the material parameters of the radial expansion pressure test simulation pipe are known, the numerical simulation software is used to take the radial expansion pressure test simulation pipe as the calculation model, and the inner wall of the calculation model is subjected to a circumferential uniform pressure. Distribute the stress P _i to simulate the radial expansion pressure generated by the static crushing agent; impose a normal displacement constraint on the contact area between the outer wall of the calculation model and the upper end face of the pressure sensor to simulate the relationship between the pressure sensor and the radial expansion pressure test simulation tube In the constraint area, the monitoring points are arranged at certain distances and the calculation is started. After the calculation, the average stress value of the monitoring points is multiplied by the area of the micro-stress equivalent area existing on the outer wall of the calculation model to calculate the outer wall of the calculation model. The received pressure F _o is used to simulate the pressure measured by the pressure sensor; then the corresponding relationship between the pressure F _o measured by the pressure sensor and _Pi is obtained through the calculation software, and the radial expansion pressure test simulates the expansion generated by the static crushing agent in the pipe. The relationship curve between the pressure _{Pi and the pressure F o on} the outer wall of the simulated pipe in the radial expansion pressure test; Step 2: Fill the static crushing agent in the radial expansion pressure test simulation tube Fill the slurry static crushing agent into the radial expansion pressure test simulation tube; or put the slurry static crushing agent into the flexible sealing bag and then put it into the radial expansion pressure test simulation tube; or combine it with the radial expansion pressure test simulation tube. The static crushing agent coils with the same inner diameter are immersed in water and placed in the radial expansion pressure test simulation tube; Step 3: Install the Radial Expansion Pressure Test Dummy Tube Align the center of the radial expansion pressure test simulation tube filled with static crushing agent with the top surface of the pressure sensor placed on the rigid base and place it on the top surface of the pressure sensor, so that the right end face of the radial expansion pressure test simulation tube and the welding Press the top column on the right side of the rigid frame; manually rotate the axial screw handle to make the axial restraint steel plate press against the left end face of the radial expansion pressure test simulation tube, and clamp the two ends of the radial expansion pressure test simulation tube Hold it between the axial restraint steel plate and the top column to restrain the axial displacement of the radial expansion pressure test simulation pipe; manually rotate the radial screw handle to make the radial restraint steel plate press against the radial expansion pressure test simulation pipe. On the upper outer wall, the radial expansion pressure test simulation tube is clamped between the radial restraint steel plate and the pressure sensor to constrain the radial displacement of the radial expansion pressure test simulation tube; Step 4: With the expansion of the static crushing agent, the radial expansion pressure is tested by the pressure sensor to test the force F _o on the outer wall of the simulated pipe, and the pressure F _o measured by the pressure sensor is collected by the pressure sensor data acquisition instrument and recorded; use step 1 The obtained relationship curve between the expansion pressure Pi generated by the static crushing agent in the simulated pipe in the expansion pressure test and the pressure F _{o on} the outer wall of the simulated pipe in the radial expansion pressure test can be obtained. The change curve of the expansion pressure _Pi with the hydration reaction time of the static crushing agent, through which the radial expansion pressure of the static crushing agent in the borehole at different hydration reaction times can be obtained.

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