Method for forming effective pile diameter vibro-replacement stone column under super-strong earthquake belt

Abstract

The application discloses a method for forming an effective pile diameter vibro-replacement stone pile under an ultra-strong earthquake zone, which comprises the following steps: installing a detection element for detecting a vibroflot deflection parameter on a shock absorber or a guide rod; penetrating a pipeline for supplying water through the vibroflot and extending the pipeline from the bottom end of the vibroflot; controlling the perpendicularity of the vibroflot according to the vibroflot deflection parameter detected by the detection element during the vibroflot construction; when the perpendicularity of the vibroflot reaches a specified perpendicularity range, the vibroflot controls the water flow of the supplied water according to the current stratum compactness to perform a vibroflot hole forming construction; and vibrating the stone filler put into the stone pile to form a vibro-replacement stone pile with an effective pile diameter after the hole forming construction is completed. The method can accelerate the vibroflot construction of the stratum with a depth of more than 50 m and thick overburden according to the stratum condition and the required perpendicularity, and can make the stone pile formed by the vibro-replacement stone filler tightly combined with the soil layer.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vibroflotation stone column, in particular to a method for forming an effective pile diameter vibroflotation stone column under an ultra-strong earthquake zone. BACKGROUND

[0002] The vibroflotation method is a method for treating the ground, which makes loose ground soil layers dense under the combined action of horizontal vibration of a vibroflotation device and high-pressure water or auxiliary high-pressure air; or after a hole is formed in the ground soil layer, a hard and coarse-grained material with stable performance is backfilled to form a reinforced body (vibroflotation pile) and a composite ground formed by the surrounding ground soil.

[0003] During the construction process using the vibroflotation method, different geological conditions of the stratum use different construction methods. If the structure of the special stratum is complex and the construction effect cannot be guaranteed under the action of horizontal vibration of the vibroflotation device, the stratum is pre-damaged by high-pressure water, which is beneficial to improve the penetration and pore-forming capacity of the vibroflotation device.

[0004] However, the provisions of the existing “Technical Code for Vibroflotation Ground Treatment of Water and Hydropower Engineering” (DL / T524-2016) regarding water supply pressure and water supply volume are only based on the experience of engineering practice (the existing construction level of domestic vibroflotation stone piles is within 35m, and all are shallow hole vibroflotation with relatively single stratum). There is no specific provision for what kind of stratum should adopt how much water pressure. For the strong earthquake zone, there are often soft interlayers (such as mucky clay deposited in lacustrine or marine environment) and relatively dense hard layers (such as sand layers or sand layers with gravel), and the problems encountered in pore-forming of these two types of stratum are completely different, so the above provisions cannot be applied.

[0005] In addition, during the construction process of the vibroflotation stone pile machine, whether the vibroflotation device can be vibroflated in accordance with the verticality requirements during the vibroflotation and densification process is an important factor affecting the quality of the vibroflotation stone pile body. However, the existing vibroflotation stone pile machine using a conventional guide rod (i.e. a guide rod with fixed length) does not have a verticality control device, and can only rely on the personal ability and responsibility of the operator to maintain the overhanging state of the vibroflotation device during the vibroflotation process. This method often causes the verticality of the vibroflotation device to not meet the requirements, and the construction process is corrected on the side, which greatly prolongs the construction period and causes losses to the owner.

[0006] In addition, the vibroflotation densification of the existing vibroflotation device is controlled according to the densification current, but the densification current cannot be accurately determined, so the vibroflotation pile obtained by controlling the vibroflotation device according to the densification current cannot be closely combined with the soil layer.

[0007] Therefore, how to construct a vibroflotation stone pile with quality meeting the requirements in the stratum of the ultra-strong earthquake zone is a problem that needs to be solved by those skilled in the art. SUMMARY

[0008] The present application aims to overcome the problems of the prior art, and provides a method for forming a vibration-impact gravel pile with an effective pile diameter under a super-strong earthquake zone, so that the vibrator can accelerate the vibration-impact construction according to the stratum conditions and the required verticality, and the vibration-impact gravel filler is tightly combined with the soil layer.

[0009] In order to achieve the above-mentioned purpose of the present application, the present application provides a method for forming a vibration-impact gravel pile with an effective pile diameter under a super-strong earthquake zone, comprising:

[0010] A detection element for detecting the deflection parameters of the vibrator is installed on the damper or the guide rod;

[0011] A pipeline for supplying water is arranged to extend out of the bottom end of the vibrator after passing through the vibrator, so that the water jetted from the bottom end of the vibrator is used to pre-damage the stratum at the hole site during the vibration-impact process;

[0012] During the vibration-impact construction of the vibrator, the verticality of the vibrator is controlled according to the deflection parameters of the vibrator detected by the detection element;

[0013] When the verticality of the vibrator reaches a specified verticality range, the vibrator controls the water flow of the supplied water according to the current stratum density to perform the vibration-impact hole construction;

[0014] After the hole construction is completed, the vibrator vibrates the gravel filler put into the gravel pile to form a vibration-impact gravel pile with an effective pile diameter.

[0015] The method for forming a vibration-impact gravel pile with an effective pile diameter comprises:

[0016] During the vibration-impact and compaction of the gravel by the vibrator, a pickup arranged on the inner side of the vibrator shell is used to detect the real-time vibration signal of the vibrator when the vibrator vibrates the gravel embedded in the soil layer around the gravel pile hole;

[0017] According to the real-time vibration signal of the vibrator detected by the pickup arranged on the inner side of the vibrator shell, the vibration-impact of the vibrator on the gravel pile is controlled, so that the vibrator vibrates the gravel filled into the gravel pile hole to form a gravel pile with a pile diameter equal to the effective pile diameter.

[0018] Preferably, the control of the vibration-impact of the vibrator on the gravel pile according to the real-time vibration signal of the vibrator detected by the pickup arranged on the inner side of the vibrator shell comprises:

[0019] The main frequency of the real-time vibration signal of the vibrator is obtained by converting the real-time vibration signal of the vibrator detected by the pickup from time domain to frequency domain;

[0020] comparing the real-time vibrator vibration signal main frequency of the vibrator with a preset frequency;

[0021] When the real-time vibrator vibration signal main frequency of the vibrator reaches or approaches the preset frequency, it is determined that the pile diameter of the stone pile to be formed is equal to the effective pile diameter, and the vibrator is lifted upward to vibrate the stones in the middle part of the stone pile to be formed, so as to finally form a stone pile with a pile diameter equal to the effective pile diameter.

[0022] When the real-time vibrator vibration signal main frequency of the vibrator is greater than the preset frequency, the vibrator is controlled to continue vibrating the stones embedded in the soil layer around the stone pile hole.

[0023] Preferably, the preset frequency is the vibrator vibration signal main frequency when the amplitude of the vibrator is reduced to the minimum value.

[0024] Preferably, the control of the vibration of the vibrator on the stone pile according to the real-time vibrator vibration signal detected by the pickup arranged inside the vibrator shell comprises:

[0025] The former vibrator vibration signal main frequency and the latter vibrator vibration signal main frequency are obtained by time-to-frequency domain conversion of the former vibrator vibration signal detected by the pickup and the latter vibrator vibration signal detected by the pickup.

[0026] The former vibrator vibration signal main frequency and the latter vibrator vibration signal main frequency obtained in the vibration period are analyzed.

[0027] When the latter vibrator vibration signal main frequency is less than the former vibrator vibration signal main frequency and remains for a period of time, it is determined that the pile diameter of the stone pile to be formed is equal to the effective pile diameter, and the vibrator is lifted upward to vibrate the stones in the middle part of the stone pile to be formed, so as to finally form a stone pile with a pile diameter equal to the effective pile diameter.

[0028] Preferably, the pickup arranged inside the vibrator shell comprises a sound sensor and an audio amplifier.

[0029] Alternatively, the pickup arranged inside the vibrator shell is a sound sensor.

[0030] Preferably, the detection of the deflection parameters of the vibrator by the detection element comprises:

[0031] The top angle and the azimuth angle of the shock absorber or the guide rod are obtained by the detection element.

[0032] The obtained top angle and azimuth angle of the shock absorber or the guide rod are determined as the top angle and the azimuth angle of the vibrator.

[0033] Preferably, the vibrator is controlled according to the vibrator deflection parameters detected by the detection element so that the vibrator performs the vibroflotation construction with the required verticality, which comprises:

[0034] The determined vibrator top angle and vibrator azimuth angle are compared with the preset vibrator top angle threshold range and azimuth angle threshold range respectively;

[0035] According to the comparison result, it is determined whether the vibrator verticality meets the requirements.

[0036] Preferably, when the vibrator verticality does not meet the requirements, the guide rod azimuth is adjusted according to the vibrator azimuth angle, and the guide rod top angle is adjusted according to the vibrator top angle, so that the vibrator verticality meets the requirements.

[0037] Preferably, the vibrator performs the vibroflotation construction according to the current stratum compactness to control the water supply flow of the water supply, which comprises:

[0038] The pipeline for supplying water is passed through the guide rod and the vibrator and extends out from the bottom end of the vibrator, so that the water is sprayed from the bottom end of the vibrator to pre-damage the stratum by water;

[0039] The current stratum compactness is obtained during the vibroflotation construction;

[0040] The instantaneous water pressure of the water supply is obtained, and the obtained instantaneous water pressure is determined as the current water pressure;

[0041] According to the preset corresponding relationship between the water pressure and the stratum compactness, the target water pressure corresponding to the current stratum compactness is searched;

[0042] The water supply flow of the water supply is controlled so that the current water pressure reaches the target water pressure, so that the vibroflotation construction of the gravel pile hole is completed by the vibrator vibroflotation and the target water pressure.

[0043] Compared with the prior art, the method for forming the effective pile diameter vibroflotation gravel pile under the super-strong earthquake zone has the following outstanding advantages:

[0044] 1、The method for forming the effective pile diameter vibroflotation gravel pile under the super-strong earthquake zone can detect the vibrator deflection parameters in real time and control the verticality of the vibrator vibroflotation construction in time during the vibroflotation construction of the complex foundation in the strong earthquake zone by the vibrator, so that the vibrator can perform the downward vibroflotation construction on the construction stratum with the required verticality, ensure the uniformity and compactness of the formed vibroflotation gravel pile diameter, improve the safety of the vibroflotation gravel pile, and effectively shorten the construction period and reduce the construction cost.

[0045] 2、The present application can control the water pressure supply accurately according to the different stratum density for the deep and thick covering complex stratum, so that the vibrator and the suitable water pressure work together to complete the complex stratum vibrator construction successfully, thereby solving the problem of the deep and thick covering stratum vibrator construction.

[0046] 3、The present application can average the vibrator current instantaneous value obtained from the uneven stratum distribution, avoid the frequent adjustment of the water supply water pressure due to the frequent mutation of the vibrator current, ensure the water pump supply level, and prolong the service life of the water pump.

[0047] 4、The method of the present application can make the gravel pile and the surrounding soil tightly combined together, so that the pile diameter of the gravel pile truly meets the design requirements. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 is a schematic diagram of the effective pile diameter vibrator gravel pile forming method of the present application under the super strong earthquake belt;

[0049] Figure 2 is a perspective view of the vibrator gravel pile machine (the detection element is installed on the guide rod);

[0050] Figure 3 is a structural schematic diagram of the vibrator, shock absorber and guide rod after assembly (the detection element is installed on the shock absorber);

[0051] Figure 4 is an elevation view when the actual guide rod is lowered and deviated;

[0052] Figure 5 is a horizontal projection view when the actual guide rod is lowered and deviated;

[0053] Figure 6 is a schematic block diagram of the water supply control system of the vibrator gravel pile machine;

[0054] Figure 7 is a method flow chart for obtaining the current stratum density of the embodiment of the present application;

[0055] Figure 8 is a water supply control method flow chart of the embodiment of the present application;

[0056] Figure 9 is a schematic diagram of the pickup set in the inside of the vibrator shell;

[0057] Figure 10 is a principle diagram of the encryption control part for controlling the vibrator to encrypt the gravel filler;

[0058] Figure 11 is Figure 10 the flow chart of the first embodiment of the encryption control part for performing vibrator encryption control in

[0059] Figure 12 is Figure 10 a flow chart of a second embodiment of the vibration encryption control part in the encryption control part. DETAILED DESCRIPTION

[0060] As Figure 1 shown, a flow chart of the method for forming an effective pile diameter vibro-replacement stone pile under the ultra-strong earthquake zone of the application, as can be seen from the figure, the method of the application comprises:

[0061] The detection element for detecting the deflection parameter of the vibrator is installed on the shock absorber or guide rod;

[0062] The pipeline for supplying water is passed through the vibrator and extends out from the bottom end of the vibrator, so that the stratum at the hole site is pre-damaged by water jetting from the bottom end of the vibrator during the vibration construction process;

[0063] During the vibration construction process of the vibrator, the verticality of the vibrator is controlled according to the deflection parameter of the vibrator detected by the detection element;

[0064] When the verticality of the vibrator reaches the specified verticality range, the vibrator controls the water flow of the supplied water according to the current stratum density to perform the vibration hole construction;

[0065] After the hole construction is completed, the vibrator vibrates the gravel filler put into the gravel pile to form a vibro-replacement stone pile with an effective pile diameter.

[0066] The vibration construction to form the gravel pile generally comprises 1) the vibrator vibrates to form a gravel pile hole, and 2) the vibrator vibrates the gravel filled into the gravel pile hole to form a gravel pile.

[0067] During the vibration hole construction and vibration encryption, in order to ensure that the verticality of the above-mentioned vibrator can always meet the requirements, so as to construct a gravel pile hole with required verticality and a vibro-replacement stone pile with good quality, uniformity, density and earthquake resistance, the deflection parameter of the vibrator during the vibration hole construction and vibration encryption is controlled.

[0068] In application, the detection element for detecting the deflection parameter of the vibrator is installed on the shock absorber or guide rod; during the vibration construction process of the vibrator, the verticality of the vibrator is controlled according to the deflection parameter of the vibrator detected by the detection element; when the verticality of the vibrator reaches the specified verticality range, the vibrator controls the water flow of the supplied water according to the current stratum density to perform the vibration hole construction; after the hole construction is completed, the vibrator vibrates the gravel filler put into the gravel pile to form a vibro-replacement stone pile with an effective pile diameter.

[0069] In which, as Figure 2As shown, the perspective view of the vibroflotation stone pile machine 1000 provided by the present application, from the figure, the vibroflotation stone pile machine 1000 of the present application comprises a hoisting system, a guide rod 10, a shock absorber 12, a vibrator 13 and an automatic feeding system.

[0070] Specifically, the hoisting system comprises a main machine of the vibroflotation stone pile machine, a mast 11 connected with the main machine, a main hoist device installed at the rear end of the main machine, the guide rod 10 is hoisted by the steel wire rope of the main hoist device and the mast 11, so that the guide rod is vertically arranged under the action of its own weight. The automatic feeding system is installed at the rear of the main machine of the hoisting system and can be used as the counterweight of the main machine, comprising an air pipe hoist device, a cable hoist device and a water pipe hoist device, and the three devices are set to synchronous feeding with the main hoist device.

[0071] The guide rod 10 is a fixed-length guide rod (i.e. a conventional guide rod), the length of which can be determined according to the actual vibration depth required, the upper connecting section is used for connecting with the steel wire rope of the main hoist device, and the lower working section is used for indirectly connecting with the vibrator 13, when assembling, as shown in Figure 3 The shock absorber 12 is arranged between the lower working section of the guide rod 10 and the vibrator 13.

[0072] In order that the vibrator of the above-mentioned vibroflotation stone pile machine can always be constructed with the required verticality during the vibration construction, the present application installs a detection element for detecting the deflection parameter of the vibrator on the upper part of the shock absorber (i.e. near the position of the guide rod) or on the guide rod, such as Figure 2 The first detection element 101 installed on the guide rod 10 in Figure 3 Or the second detection element 121 installed on the upper part of the shock absorber 12 in, so that the deflection parameter of the vibrator can be obtained in real time through the detection element.

[0073] Wherein, the vibrator motor transmits power to the main shaft through the connecting flange, the shaft coupling and the like, and drives the main shaft to rotate, and the main shaft drives the eccentric block to rotate to generate centrifugal force, which is the excitation force of the vibrator, the excitation force makes the shell produce high-frequency vibration, and the vibrator realizes the vibration operation through the shell.

[0074] The inventor finds that when the center of mass of the eccentric block of the vibrator deviates from the center of mass of the vibrator shell and is below the center of mass of the vibrator shell, the amplitude of each point of the vibrator shell along the length direction is in a triangular distribution, and the intersection with the center line of the vibrator is the zero amplitude point. When designing, the center of mass of the shock absorber should be coincided with the zero amplitude point, and at this time, the shock absorption and shock isolation effect of the shock absorber is the best, and the service life is also long. Since the upper part of the shock absorber and the guide rod are located above the upper part of the vibrator and above the zero amplitude point of the vibrator, the upper part of the shock absorber and the upper part are not affected by the horizontal vibration force of the vibrator during the vibrator vibration construction process. Therefore, the detection element is installed on the upper part of the shock absorber (at a position above the center of mass of the shock absorber) or the guide rod (preferably, near the lower part of the shock absorber), and the data detected by the detection element represent the deflection parameters of the vibrator, so as to ensure the feasibility and accuracy of the verticality detection of the vibrator during the vibrator vibration construction.

[0075] And the deflection parameters of the vibrator detected by the detection element include:

[0076] The top angle and the azimuth angle of the shock absorber or the guide rod are obtained through the detection element;

[0077] The obtained top angle and azimuth angle of the shock absorber or the guide rod are determined as the top angle and the azimuth angle of the vibrator.

[0078] In the present application, the detection element is fixed on the upper part of the shock absorber or the guide rod by the fixing method in the prior art. The deflection parameters of the vibrator include the top angle and the azimuth angle of the vibrator.

[0079] When the detection element is installed on the upper part of the shock absorber, the top angle and the azimuth angle detected by the detection element are considered as the top angle and the azimuth angle of the shock absorber. When the detection element is installed on the guide rod, the top angle and the azimuth angle detected by the detection element are considered as the top angle and the azimuth angle of the guide rod. In the present application, since the guide rod, the shock absorber and the vibrator are coaxial, and during the vibration construction process, the three are still coaxial, and the installation position of the detection element is close to the top of the vibrator, the top angle and the azimuth angle of the shock absorber or the top angle and the azimuth angle of the guide rod detected by the detection element are determined as the top angle and the azimuth angle of the vibrator, that is, the determined top angle and the azimuth angle of the vibrator are the deflection parameters of the vibrator.

[0080] In this invention, the verticality of the guide rod, shock absorber, and vibratory compactor lowered along the vertical direction is considered to be 0. That is, the guide rod, etc., lowered along the vertical direction are perpendicular to the cross-section of the vertical pile hole. When the guide rod, shock absorber, and vibratory compactor are regarded as a whole vibratory compaction assembly, such a vibratory compaction assembly is called the theoretical vibratory compaction assembly. However, during actual vibratory compaction, the vibratory compaction assembly formed by the actual guide rod, etc., will have a certain angle with the vertical line. That is, the actual vibratory compaction assembly will be somewhat deviated from the theoretical vibratory compaction assembly along the vertical direction, and the deviated angles of the actual guide rod, actual shock absorber, and actual vibratory compactor in the actual vibratory compaction assembly are the same relative to the theoretical guide rod, theoretical shock absorber, and theoretical vibratory compactor in the theoretical vibratory compaction assembly along the vertical direction. In this invention, the apex angle of the guide rod refers to the angle θ between the actual lowered (or extended) guide rod and the theoretical guide rod that should have been lowered (or extended) along the vertical direction. Correspondingly, the angle between the actual lowered shock absorber and the theoretical shock absorber is also θ. Similarly, the angle between the actual lowered vibratory impactor and the theoretical vibratory impactor is also θ (e.g., Figure 4 The diagram shows the apex angle of the vibratory compactor when the actual vibratory compactor assembly is lowered at an angle. The azimuth angle of the damper, relative to the tilted (or extended) guide rod, refers to the direction projected onto the horizontal plane from the lowering direction of the actual guide rod. Using north as the reference (0° position), the angle between the reference north and the actual guide rod's lowering direction clockwise is the guide rod's azimuth angle α. Similarly, the direction projected onto the horizontal plane from the lowering direction of the actual vibratory compactor assembly, using north as the reference (0° position), is also the same as the damper's azimuth angle α. That is, the azimuth angles of the vibratory compactor and guide rod are also the same as the damper's azimuth angle α (e.g., ...). Figure 5 As shown, the azimuth angle of the actual vibratory impact assembly OA is shown during the tilted lowering, where one clockwise rotation is 360° (0° position is also 360° position). For example, the actual lowering of the vibratory impact assembly along the horizontal projection direction... Figure 5 In the OA direction (α is 290°), the azimuth angle of the shock absorber and guide rod is 290°. Correspondingly, the azimuth angle of the vibratory compactor is determined to be 290°. At this point, the actual downward direction of the vibratory compactor is northwest (northwest) 70°. However, if the shock absorber and other components are completely vertical, the apex angle of the vibratory compactor is 0°, and the azimuth angle of the vibratory compactor is 0° (i.e., the vibratory compactor assembly is in...). Figure 5 The horizontal projection is point O, which coincides with the point on the horizontal projection of the centerline of the pile hole (the centerline is along the vertical direction). This means that the vibratory compactor does not have a skew problem. In other words, the azimuth angle is used to characterize the skew direction of the vibratory compactor assembly, so as to adjust the actual lowering direction of the vibratory compactor assembly accordingly.

[0081] The above method controls the verticality of the vibratory punch based on the skew parameters detected by the detection element, so that the verticality of the vibratory punch reaches the specified verticality range. This method is applicable to the process of vibratory punching for hole making and vibratory punching for densification.

[0082] And in the process of vibroflotation, when the vibroflotation reaches the specified verticality range, the vibroflotation also controls the water supply flow of the water supply according to the current stratum density to carry out vibroflotation construction.

[0083] Wherein, the pipeline for supplying water is passed through the vibroflotation and extends from the bottom end of the vibroflotation, so that the water sprayed from the bottom end of the vibroflotation is used to pre-damage the stratum at the hole site during the vibroflotation process.

[0084] Wherein, the water control method of the vibroflotation stone pile machine forms a stone pile hole by obtaining the current stratum density during the vibroflotation construction, and controlling the water flow of the water supply in real time according to the current stratum density, so that the vibroflotation and the water jointly act to quickly vibroflotation the stone pile hole.

[0085] The present application automatically controls the supply amount of water according to the current stratum density, which is suitable for shallow hole vibroflotation with relatively single stratum and deep hole vibroflotation with complex stratum, and ensures the smooth progress of shallow hole or deep hole vibroflotation construction.

[0086] As shown in Figure 8 , the present embodiment provides a water control method of a vibroflotation stone pile machine, which comprises:

[0087] S100, the pipeline for supplying water is passed through the vibroflotation and extends from the bottom end of the vibroflotation, so that the water sprayed from the bottom end of the vibroflotation is used to pre-damage the stratum;

[0088] S101, obtaining the current stratum density during the vibroflotation construction;

[0089] S102, obtaining the instantaneous water pressure of the water supply, and determining the obtained instantaneous water pressure as the current water pressure;

[0090] S103, according to the preset corresponding relationship between the water pressure and the stratum density, finding the target water pressure corresponding to the current stratum density;

[0091] S104, controlling the water flow of the water supply to make the current water pressure reach the target water pressure, so as to complete the vibroflotation construction by using the vibroflotation and the target water pressure.

[0092] As shown in Figure 7 , S101 obtaining the current stratum density during the vibroflotation construction comprises:

[0093] S201, obtaining the current vibroflotation current of the vibroflotation;

[0094] S202, according to the preset corresponding relationship between the vibroflotation current and the stratum density, finding the stratum density corresponding to the current vibroflotation current;

[0095] S203, the found formation density is determined as the current formation density.

[0096] like Figure 2 As shown, the vibrator 3 is connected to the controller 1 through the vibrator frequency converter cabinet 2. The vibrator frequency converter cabinet 2 and the controller 1 are connected wirelessly or wiredly.

[0097] In one embodiment of this example, when encountering a locally uniformly distributed stratum, the instantaneous value of the obtained oscillating current is stable. S201 obtains the current oscillating current of the oscillator in the following way: obtains the instantaneous value of the oscillating current of the oscillator; and determines the obtained instantaneous value of the oscillating current as the current oscillating current.

[0098] In this implementation, controller 1 obtains the vibration current signal of vibrator 3 from vibrator inverter cabinet 2 and determines the obtained vibration current as the current vibration current. Alternatively, a current detection sensor (not shown in the figure) is installed on the vibration output line of vibrator 3 connected to vibrator inverter cabinet 2; when vibrator 3 is started, the current detection sensor generates a vibration current signal, which is transmitted to controller 1 in real time via wired or wireless means. Controller 1 determines the vibration current transmitted from the current detection sensor in real time as the current vibration current. The current detection sensor can be any sensor capable of detecting current in the prior art, such as a current transformer.

[0099] In another embodiment of this example, when encountering locally unevenly distributed strata, the instantaneous values ​​of the acquired vibratory current jump significantly. S201 acquires the current vibratory current of the vibrator in the following way: acquire multiple instantaneous values ​​of the vibratory current; average the acquired multiple instantaneous values ​​of the vibratory current to obtain the average vibratory current; and determine the average vibratory current as the current vibratory current. The time interval between acquiring two adjacent instantaneous values ​​of the vibratory current is equal. The method for averaging the acquired multiple instantaneous values ​​of the vibratory current is as follows: n (n≥2) consecutively acquired instantaneous values ​​of the vibratory current are grouped into a queue, and the n instantaneous values ​​in the queue are summed and averaged; each newly acquired instantaneous value of the vibratory current is added to the tail of the queue, while the first instantaneous value of the vibratory current is removed, forming a new queue, and the n instantaneous values ​​in the new queue are summed and averaged.

[0100] The method for acquiring the instantaneous value of the jolt current in the embodiment is described in the foregoing embodiments. Specifically, the current average processing module can be arranged in the controller. The controller acquires the instantaneous value of the jolt current from the frequency converter cabinet 2 of the jolter or the current detection sensor, and performs average processing on n (n≥2) instantaneous values of the jolt current in the queue through the current average processing module to obtain the average jolt current. The controller determines the average jolt current as the current jolt current.

[0101] In S202, the current jolt current is determined as the current jolt current according to the preset corresponding relationship between the jolt current and the stratum compactness. In S203, the stratum compactness corresponding to the current jolt current is searched according to the preset corresponding relationship between the jolt current and the stratum compactness, and the searched stratum compactness is determined as the current stratum compactness. The specific implementation is as follows:

[0102] The controller is preset with the corresponding relationship between the jolt current and the stratum compactness. The corresponding relationship between the jolt current and the stratum compactness is obtained through tests, that is, a test pile is first made on site before formal construction, and the controller determines the corresponding relationship between the jolt current and the stratum compactness according to a large amount of data obtained through the test pile.

[0103] In one embodiment of the present embodiment, the corresponding relationship between the jolt current and the stratum compactness is shown in Table 1. The stratum compactness is divided into three levels of soft, medium and hard, and the corresponding relationship between the stratum compactness of different levels and the jolt current is obtained through field test data.

[0104] Table 1: Corresponding relationship between jolt current and stratum compactness

[0105]

[0106]

[0107] In Table 1, Ie is the rated current of the jolter.

[0108] After the controller acquires the current jolt current, the stratum compactness corresponding to the current jolt current is determined as the current stratum compactness through Table 1. For example, when the controller 1 acquires the current jolt current I=0.3Ie, the current stratum compactness is determined as medium through Table 1.

[0109] It should be noted that Table 1 only shows one corresponding relationship between the jolt current and the stratum compactness. For more complex strata, the controller can also obtain other more complex corresponding relationships according to field test data.

[0110] In S102, the instantaneous pressure of the supply water is acquired, and the acquired instantaneous pressure of the supply water is determined as the current pressure of the supply water. The specific implementation is as follows:

[0111] As Figure 6As shown, a water supply pressure detection sensor 41 is installed on the outlet pipe of the water pump 4 to obtain the instantaneous water pressure supplied by the water pump 4 and transmit it to the controller 1. The controller 1 determines the instantaneous water pressure transmitted from the water supply pressure detection sensor 41 as the current water pressure.

[0112] Because screw pumps have the characteristics of pulsation-free water supply pressure and stable instantaneous flow rate, this embodiment uses a screw pump to supply sewage. However, other pumps with pulsation-free water supply pressure and stable instantaneous flow rate can also be used, as long as the supplied sewage pressure and flow rate meet the requirements. A water supply pressure detection sensor 41 is installed on the outlet pipe of the screw pump to obtain the instantaneous sewage pressure supplied by the screw pump. The water supply pressure detection sensor 41 can be any sensor capable of detecting water pressure available in the prior art. For example, a pressure transmitter can be used.

[0113] In addition, such as Figure 6 As shown, a water supply flow detection sensor 42 is also installed on the outlet pipe of water pump 4 to detect the instantaneous flow rate of water supplied by water pump 4 in real time. The water supply flow detection sensor 42 can be any sensor capable of detecting water flow rate in the prior art. For example, an electromagnetic flow meter can be used. The water supply flow detection sensor 42 transmits the detected instantaneous flow rate of water supplied by water pump 4 to controller 1, and the controller determines the instantaneous flow rate as the current flow rate.

[0114] like Figure 6 As shown, the water supply pressure detection sensor 41 and the water supply flow detection sensor 42 transmit the real-time detected instantaneous water pressure signal and instantaneous water flow signal to the remote terminal unit (RTU), and the RTU transmits the signal to the controller 1 wirelessly.

[0115] Specifically, S103, based on the preset correspondence between groundwater pressure and formation density, finds the target groundwater pressure corresponding to the current formation density. The specific implementation method is as follows:

[0116] The controller has a pre-set relationship between water pressure and soil density. This relationship is obtained through testing; that is, test piles are built on-site before formal construction, and the controller analyzes the large amount of data obtained from the test piles to determine the relationship between water pressure and soil density.

[0117] In one embodiment of this example, the relationship between groundwater pressure and formation density is shown in Table 2. Formation density is divided into three levels: soft, medium, and hard. The relationship between different levels of formation density and groundwater pressure is obtained through field test data.

[0118] Table 2. Correspondence between groundwater pressure and formation density

[0119] Discharge pressure P (MPa) Formation compactness Dr 0.3～0.5 Soft 0.5～0.7 Medium 0.7～0.8 Hard

[0120] Controller 1 uses lookup table 2 to find the target groundwater pressure corresponding to the current formation density. As shown in Table 2, upper and lower limits are set for the groundwater pressure corresponding to each level of formation density. For example, when controller 1 determines the current formation density to be medium using lookup table 1, it uses lookup table 2 to find the target groundwater pressure corresponding to the medium-level current formation density, which is 0.5–0.7 MPa.

[0121] It should be noted that Table 2 only shows one relationship between groundwater pressure and formation density. For more complex formations, the controller can obtain other more complex relationships based on field test data.

[0122] S104 controls the flow rate of the supplied sewage to make the current sewage pressure reach the target sewage pressure. The specific implementation method is as follows: compare the current sewage pressure and the target sewage pressure to obtain the difference between the current sewage pressure and the target sewage pressure; the controller controls the flow rate of the pump to supply sewage based on the difference between the current sewage pressure and the target sewage pressure to make the current sewage pressure reach the target sewage pressure.

[0123] Specifically, the controller controls the flow rate of water supplied by pump 4 based on the difference between the current drainage pressure and the target drainage pressure, including: when the current drainage pressure is greater than the upper limit of the target drainage pressure, controlling pump 4 to reduce the drainage flow rate; when the current drainage pressure is less than the lower limit of the target drainage pressure, controlling pump 4 to increase the drainage flow rate; and when the current drainage pressure is within the range of the target drainage pressure, controlling pump 4 to maintain the drainage flow rate.

[0124] like Figure 6 As shown, in this embodiment, the water pump 4 is connected to the controller 1 via the water pump frequency converter cabinet 5. The water pump frequency converter cabinet 5 and the controller 1 are connected wirelessly, but a wired connection can also be used. The controller 1 controls the speed of the water pump 4 by changing the output frequency of the water pump frequency converter cabinet 5, thereby changing the flow rate of the water supplied by the water pump 4. When the flow rate of the water discharged from the water pump outlet pipe increases, the water pressure also increases; when the flow rate of the water discharged from the water pump outlet pipe decreases, the water pressure also decreases.

[0125] The water control process in this embodiment is as follows:

[0126] 1. After the vibratory flusher 3 is started, the water supply pressure detection sensor 41 detects the instantaneous water pressure in real time, and the water supply flow detection sensor 42 detects the instantaneous water flow in real time.

[0127] 2. Controller 1 acquires the current vibration current, current drainage pressure, and current drainage flow rate;

[0128] 3. The controller 1 looks up the current stratum density corresponding to the current shock current according to the obtained current shock current look-up table 1, and looks up the target water injection pressure corresponding to the current stratum density according to the look-up table 2;

[0129] 4. The controller 1 compares the obtained current water injection pressure with the looked-up target water injection pressure, converts the difference into a control signal, and controls the output frequency of the water pump frequency conversion cabinet 5, so as to change the water injection flow rate of the water pump 4 by controlling the rotating speed of the water pump 4, and further change the water injection pressure, so that the current water injection pressure is within the target water injection pressure range.

[0130] After the shocker reaches the specified verticality range and performs the shock hole construction according to the current stratum density control of the supplied water injection flow rate, the gravel filler is put into the gravel pile hole, the vibrator performs the shock compaction on the gravel filler put into the gravel pile, and the shock gravel pile with the effective pile diameter is formed.

[0131] The shock gravel pile with the effective pile diameter includes:

[0132] During the shock compaction of the gravel by the shocker, the pickup 1311 arranged inside the shell of the shocker is used to detect the real-time vibration signal of the shocker when the shocker vibrates the gravel embedded in the soil layer around the gravel pile hole;

[0133] According to the real-time vibration signal of the shocker detected by the pickup 1311 arranged inside the shell of the shocker, the shock of the shocker on the gravel pile is controlled, so that the pile diameter of the gravel pile formed by the shock of the shocker on the gravel filled in the gravel pile hole is equal to the effective pile diameter.

[0134] The effective pile diameter of the gravel pile of the present application refers to the pile diameter of the gravel pile formed in the gravel pile hole and tightly combined with the soil layer around the hole. The effective pile diameter of the gravel pile of the present application has the following meanings:

[0135] First, the gravel pile formed in the gravel pile hole is tightly combined with the soil layer around the hole;

[0136] Second, the effective pile diameter of the gravel pile is the pile diameter of the gravel pile when the shock compaction requirement is met, so that the actual pile diameter does not need to be calculated during the shock construction process, and the shock construction process is accelerated.

[0137] Figure 9 The structure of the shocker of the present application is shown, and the difference between the shocker of the present application and the existing shocker is that a pickup 1311 for picking up sound and a support rod 1312 for fixing the pickup 1311 are arranged inside the shell 1308 of the shocker, and the support rod 1312 is fixed to the shell of the motor 1304 through the through hole of the bearing seat for supporting the shaft 1306. Figure 9The displayed vibrator 13 also includes a sling 1301, a water pipe 1302, a cable 1303, a motor 1304, a coupling 1305, a shaft 1306, an eccentric block 1307, a housing 1308, a fin 1309, a lower water pipe 1310, and a pickup 1311.

[0138] After the stone pile hole is formed, the vibrator starts to compact the stone filler by powering the motor 1304. The filler in the compaction section is squeezed into the original stratum in the horizontal direction under the excitation force of the vibrator, and the upper filler falls in the mud under the action of gravity, and the height of the filler can be measured in real time. As the compaction process proceeds, the following phenomena occur:

[0139] First, the compaction current gradually increases;

[0140] Second, the excitation force at the vibrator shell increases;

[0141] Third, the amplitude of the vibrator decreases;

[0142] Fourth, the filler around the vibrator is gradually compacted, and a stone pile body is gradually formed, which is roughly circumferential, with the maximum compaction degree in the vibration range around the vibrator, and the lateral pressure provided by the original stratum is basically equivalent when reaching the pile hole periphery.

[0143] The prior art mainly controls the compaction of the stone filler according to the compaction current of the motor 1304, but there are the following four problems:

[0144] First, the physical and engineering significance is not clear, and there is no direct relationship with the compaction degree. The compaction current needs to be determined by experiment, and the compaction degree data of the pile body can be obtained by testing after the experiment. However, when the depth of the stone pile is as high as 70m or even up to 100m, the compaction degree data of the pile body cannot be obtained by traditional experiments at this depth, so the compaction current cannot be determined by experiments;

[0145] Second, different models and different power vibrators have different currents in different strata;

[0146] Third, from the engineering practice, even the same model vibrators from the same manufacturer have a large difference in no-load current;

[0147] Fourth, in relatively cold areas, the no-load current of the vibrator is large when it is first used; and as the project develops, the temperature of the vibrator itself rises, and the no-load current decreases.

[0148] Therefore, the compaction current cannot represent the compaction degree of the pile body under the condition of super-deep overburden.

[0149] In order to solve the above problems of the prior art, the present application proposes a technique for controlling the vibration compactor to perform vibration compaction (i.e., to vibrate the gravel filler) according to the frequency of the vibration signal of the vibration compactor when the vibration compactor vibrates the gravel filler. The core technique of the compaction technique is:

[0150] In the process of vibrating the gravel filler around the vibration compactor 13, the vibration compactor real-time vibration signal when the vibration compactor vibrates the gravel embedded in the soil layer around the gravel pile hole is detected by the pickup arranged inside the vibration compactor shell;

[0151] According to the vibration compactor real-time vibration signal detected by the pickup arranged inside the vibration compactor shell, the vibration of the vibration compactor on the gravel pile is controlled, so that the vibration compactor vibrates the gravel filled in the gravel pile hole to form a gravel pile with a pile diameter equal to the effective pile diameter.

[0152] The present application controls the vibration of the vibration compactor on the gravel pile according to the vibration compactor real-time vibration signal detected by the pickup 1311 arranged inside the vibration compactor shell, which includes:

[0153] The vibration compactor real-time vibration signal main frequency is obtained by converting the vibration compactor real-time vibration signal detected by the pickup from time domain to frequency domain;

[0154] The vibration compactor real-time vibration signal main frequency is compared with the preset frequency;

[0155] When the vibration compactor real-time vibration signal main frequency reaches or approaches the preset frequency, it is judged that the pile diameter of the gravel pile to be formed is equal to the effective pile diameter, and the vibration compactor is lifted upward to vibrate the gravel in the middle part of the gravel pile to be formed, thereby finally forming a gravel pile with a pile diameter equal to the effective pile diameter;

[0156] When the vibration compactor real-time vibration signal main frequency is greater than the preset frequency, the vibration compactor is controlled to continue vibrating the gravel embedded in the soil layer around the gravel pile hole.

[0157] The preset frequency of the present application is the vibration compactor vibration signal main frequency when the amplitude of the vibrator is reduced to the minimum.

[0158] The present application controls the vibration of the vibration compactor on the gravel pile according to the vibration compactor real-time vibration signal detected by the pickup arranged inside the vibration compactor shell, which includes:

[0159] The former vibration compactor vibration signal main frequency and the latter vibration compactor vibration signal main frequency are obtained by converting the former vibration compactor vibration signal and the latter vibration compactor vibration signal detected by the pickup from time domain to frequency domain;

[0160] analyze the frequency of the main frequency of the vibration signal of the former vibrator and the frequency of the main frequency of the vibration signal of the latter vibrator obtained in the vibration period;

[0161] When the frequency of the main frequency of the vibration signal of the latter vibrator is less than the frequency of the main frequency of the vibration signal of the former vibrator and keeps for a period of time, it is judged that the pile diameter of the stone pile to be formed is equal to the effective pile diameter, and the vibrator is lifted upward to vibrate the stones in the middle part of the stone pile to be formed, so as to finally form the stone pile with the pile diameter equal to the effective pile diameter.

[0162] The pickup provided inside the vibrator shell of the present application comprises a sound sensor and an audio amplifier.

[0163] The pickup provided inside the vibrator shell of the present application can also be a sound sensor.

[0164] Figure 10 The control part for controlling the vibration encryption control of the vibrator on the stone filling is shown, which comprises a pickup 1311 for converting the vibration signal on the vibrator shell into corresponding electric signal, an audio analysis module for audio analysis of the electric signal output by the pickup 1311, a processor for processing the audio output by the audio analysis module, a memory for storing the data output by the processor, and a display for displaying the data output by the processor.

[0165] In addition, the processor is also connected with the main hoisting device, so as to lift the vibrator 13 upward when it is judged that the pile diameter of the stone pile to be formed is equal to the effective pile diameter.

[0166] The pickup 1311 of the present application can comprise a sound sensor and an audio amplifier, or only a sound sensor.

[0167] The audio analysis module, the processor, the memory and the display of the present application can be provided on the ground, and the audio analysis module can be connected with the pickup through a cable. In addition, the audio analysis module of the present application can be a Fourier transformer for converting the vibration signal from time domain to frequency domain.

[0168] Compared with the pressure sensor installed on the outer shell of the vibrator in another patent application of the present inventor, the present application can greatly prolong the service life of the sound sensor. That is, since the sound sensor 1311 is installed inside the vibrator shell, it is not easily damaged like the pressure sensor installed on the outer shell of the vibrator, which is extruded by the stone filling and the vibrator.

[0169] Figure 11 The control flow of the first embodiment for controlling the vibration encryption control of the vibrator is shown, which is mainly implemented by the processor and specifically comprises:

[0170] Step S301, detecting the real-time vibration signal of the vibrator shell by the pickup during the vibrator is vibrating the gravel fill;

[0171] Step S302, obtaining the main frequency of the vibrator real-time vibration signal by converting the vibrator real-time vibration signal detected by the pickup from time domain to frequency domain

[0172] Step S303, judging whether the main frequency of the vibrator real-time vibration signal reaches or approaches the preset frequency;

[0173] Step S304, when the judgment result of step S302 is yes, judging that the pile diameter of the gravel pile to be formed is equal to the effective pile diameter;

[0174] Step S305, lifting the vibrator upward to vibrate the gravel of the middle part of the gravel pile to be formed, so as to finally form the gravel pile with the pile diameter equal to the effective pile diameter;

[0175] Step S306, when the judgment result of step S302 is no, controlling the vibrator to continue vibrating the gravel embedded in the soil layer around the gravel pile hole.

[0176] Figure 12 The control flow of the second embodiment of controlling the vibrator to vibrate and encrypt is shown, which comprises:

[0177] Step S401, obtaining the former vibrator vibration signal detected by the pickup before and the latter vibrator vibration signal detected by the pickup after by detecting the real-time vibration signal of the vibrator shell by the pickup during the vibrator is vibrating the gravel fill;

[0178] Step S402, obtaining the main frequency of the former vibrator vibration signal and the main frequency of the latter vibrator vibration signal by converting the former vibrator vibration signal detected by the pickup before and the latter vibrator vibration signal detected by the pickup after from time domain to frequency domain;

[0179] Step S403, judging whether the main frequency of the latter vibrator vibration signal is less than the main frequency of the former vibrator vibration signal;

[0180] Step S404, if the judgment result of step S403 is yes, further judging whether the main frequency of the latter vibrator vibration signal detected remains unchanged within a period of time;

[0181] Step S405, if the judgment result of step S404 is yes, judging that the pile diameter of the gravel pile to be formed is greater than or equal to the effective pile diameter;

[0182] Step S405, lifting the vibrator upward, and vibrating the gravel to be formed in the middle part of the gravel pile, so as to form the gravel pile with the pile diameter greater than or equal to the effective pile diameter;

[0183] Step S406, if the result of the judgment in step S403 or step S404 is no, then controlling the vibrator to continue vibrating the gravel embedded in the soil layer around the gravel pile hole.

[0184] It should be pointed out that one of the features of the present application is to propose the concept of effective pile diameter, that is, the pile diameter of the gravel pile formed in the gravel pile hole and the soil layer around the hole is tightly combined and meets the vibration compaction requirement.

[0185] The effective pile diameter of the gravel pile of the present application solves the technical problem that the gravel pile in the prior art may not be tightly combined with the soil layer.

[0186] Although the present application has been described in detail above, the present application is not limited thereto, and those skilled in the art can make modifications according to the principles of the present application, therefore, all kinds of modifications made according to the principles of the present application should be understood as falling within the scope of protection of the present application.

Claims

1. A method for forming a vibro-replacement stone column with an effective column diameter in an ultra-strong seismic zone, comprising: installing a detection element for detecting a deflection parameter of the vibrator at a position above the center of gravity of the shock absorber or a lower part of the guide rod close to the shock absorber; passing a pipeline for supplying water through the vibrator and extending from the bottom end of the vibrator to pre-destroy the stratum at the hole site by water jetting from the bottom end of the vibrator during the vibro-replacement process; controlling the verticality of the vibrator according to the deflection parameter of the vibrator detected by the detection element during the vibro-replacement process; controlling the water flow of the water supplied by the vibrator according to the current stratum density when the verticality of the vibrator reaches a specified verticality range during the vibro-replacement process; vibrating the stone fillings in the stone column to form a vibro-replacement stone column with an effective column diameter after the vibro-replacement process is completed; wherein the forming of the vibro-replacement stone column with an effective column diameter comprises: detecting the real-time vibration signal of the vibrator when vibrating the stones embedded in the soil layer around the stone column hole by using a pickup arranged inside the vibrator shell during the vibrating and compaction of the stones by the vibrator; controlling the vibration of the vibrator on the stone column according to the real-time vibration signal of the vibrator detected by the pickup arranged inside the vibrator shell, so that the vibrator vibrates the stones filled in the stone column hole to form a stone column with a column diameter equal to the effective column diameter. 2.The method according to claim 1, wherein the controlling of the vibration of the vibrator on the stone column according to the real-time vibration signal of the vibrator detected by the pickup arranged inside the vibrator shell comprises: obtaining the main frequency of the real-time vibration signal of the vibrator by converting the real-time vibration signal of the vibrator detected by the pickup from time domain to frequency domain; comparing the main frequency of the real-time vibration signal of the vibrator with a preset frequency; judging that the column diameter of the stone column to be formed is equal to the effective column diameter when the main frequency of the real-time vibration signal of the vibrator reaches or approaches the preset frequency, and lifting the vibrator upward to vibrate the stones in the middle part of the stone column to be formed, so as to finally form a stone column with a column diameter equal to the effective column diameter; controlling the vibrator to continue vibrating the stones embedded in the soil layer around the stone column hole when the main frequency of the real-time vibration signal of the vibrator is greater than the preset frequency. 3.The method according to claim 2, wherein the preset frequency is the main frequency of the vibration signal of the vibrator when the amplitude of the vibrator is reduced to the minimum. 4.The method according to claim 1, wherein the controlling of the vibration of the vibrator on the stone column according to the real-time vibration signal of the vibrator detected by the pickup arranged inside the vibrator shell comprises: obtaining the main frequency of the previous vibration signal of the vibrator and the main frequency of the subsequent vibration signal of the vibrator by converting the previous vibration signal of the vibrator detected by the pickup and the subsequent vibration signal of the vibrator from time domain to frequency domain; analyzing the main frequency of the previous vibration signal of the vibrator and the main frequency of the subsequent vibration signal of the vibrator obtained within the vibration period; When the frequency of the post-vibrator vibration signal is less than the frequency of the pre-vibrator vibration signal and remains for a period of time, it is determined that the pile diameter of the to-be-formed stone pile is equal to the effective pile diameter, and the vibrator is lifted upward to vibrate the stones in the middle part of the to-be-formed stone pile, so as to finally form a stone pile with a pile diameter equal to the effective pile diameter.

5. The method of claim 2 or 4, the pickup provided inside the vibrator housing comprises a sound sensor and an audio amplifier.

6. The method of claim 1, wherein detecting the deflection parameters of the vibrator by the detection element comprises: obtaining the top angle and azimuth angle of the shock absorber or guide rod by the detection element; determining the obtained top angle and azimuth angle of the shock absorber or guide rod as the top angle and azimuth angle of the vibrator.

7. The method of claim 6, wherein controlling the vibrator according to the deflection parameters of the vibrator detected by the detection element so that the vibrator performs vibration construction with a required verticality comprises: comparing the determined top angle and azimuth angle of the vibrator with a preset threshold range of the top angle and azimuth angle of the vibrator, respectively; determining whether the verticality of the vibrator meets the requirement according to the comparison result.

8. The method of claim 7, wherein when the verticality of the vibrator does not meet the requirement, adjusting the azimuth of the guide rod according to the azimuth angle of the vibrator and adjusting the top angle of the guide rod according to the top angle of the vibrator so that the verticality of the vibrator meets the requirement.

9. The method of claim 1, wherein the vibrator controls the jet flow of the supplied jet according to the current stratum density to perform vibration construction for hole making comprises: obtaining the current stratum density during the vibration construction; obtaining the instantaneous jet pressure of the supplied jet and determining the obtained instantaneous jet pressure as the current jet pressure; looking up a target jet pressure corresponding to the current stratum density according to a preset corresponding relationship between the jet pressure and the stratum density; controlling the jet flow of the supplied jet so that the current jet pressure reaches the target jet pressure, so as to complete the vibration construction of the stone pile hole by the vibration of the vibrator and the target jet pressure.

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