CN116791683A

CN116791683A - Water permeability detection control method for construction of ultra-deep vibroflotation gravel pile in ultra-strong earthquake zone

Info

Publication number: CN116791683A
Application number: CN202210255866.1A
Authority: CN
Inventors: 孙亮; 汤勇军; 牟毓; 赵军; 丁海龙; 薛正伟; 曹杰; 谭修桥; 张家俊; 刘保柱; 周建华; 虎元强; 郑元凯
Original assignee: Sinohydro Foundation Engineering Co Ltd
Current assignee: Sinohydro Foundation Engineering Co Ltd
Priority date: 2022-03-15
Filing date: 2022-03-15
Publication date: 2023-09-22

Abstract

The invention discloses a water permeability detection control method for ultra-deep vibroflotation gravel pile construction of an ultra-strong seismic zone, which comprises the following steps: rapidly completing vibroflotation construction of a broken stone pile hole; putting the gravel filler into a gravel pile hole, and carrying out vibroflotation encryption construction on the gravel filler in the gravel pile hole by using a vibroflotation device; during vibroflotation encryption construction, acquiring the slurry density of slurry above the gravel filler level in a gravel pile hole; and controlling the flow rate of the sewage supplied by the sewage and the flow rate of the sewage supplied by the sewage according to the obtained slurry density, and completing the vibroflotation encryption construction of the crushed stone filler by the vibroflotation device under the synergistic effect of the sewage and the sewage, thereby forming the vibroflotation crushed stone pile which meets the water permeability requirement and has an effective pile diameter. The method of the invention ensures that the ultra-deep vibroflotation gravel pile formed under the ultra-deep overburden layer of the ultra-strong seismic zone has good water permeability, is tightly combined with surrounding soil layers, can vertically upload deep ultra-static pore water pressure to the gravel cushion layer under the condition of strong earthquake, and ensures the safety of the vibroflotation gravel pile under the condition of strong earthquake.

Description

Water permeability detection control method for construction of ultra-deep vibroflotation gravel pile in ultra-strong earthquake zone

Technical Field

The invention relates to the technical field of pile machine construction, in particular to a water permeability detection control method for ultra-deep vibroflotation gravel pile construction of an ultra-strong earthquake zone.

Background

The vibroflotation method is a foundation treatment method, and the loose foundation soil layer is vibrated and sealed under the combined action of horizontal vibration of a vibroflotation device and high-pressure water or high-pressure air; or after the holes are formed in the foundation layer, backfilling hard coarse particle materials with stable performance, and forming a composite foundation by a reinforcement (vibroflotation pile) formed by vibration compaction and surrounding foundation soil.

In the process of construction by using the vibroflotation method, the strata under different geological conditions are different in construction method, if a special stratum with a complex structure is encountered, and when the construction effect cannot be guaranteed under the combined action of horizontal vibration of the vibroflotation device and high-pressure water, high-pressure air can be used as an aid, and the stratum is punched and pre-destroyed under the combined action of the high-pressure water and the high-pressure air, so that the penetration and pore-forming capability of the vibroflotation device is improved.

However, the regulations on water supply pressure and water supply amount in the technical Specification of Foundation treatment by the Water and Water conservancy project vibroflotation (DL/T524-2016) are summarized according to the experience of engineering practice (the existing construction level of the domestic vibroflotation gravel pile is within 35m and the stratum is shallow Kong Zhenchong relatively single), only one approximate range of water supply pressure and water supply amount of a water pump is provided, and no specific regulations are provided on what stratum should adopt how much water pressure. For ultra-deep overburden layers, where the overburden thickness is at most 100m or more, the problems encountered in pore-forming of the two formations are quite different due to the presence of a weak interlayer (e.g. lake-phase deposited muddy clay) and a relatively dense hard layer (e.g. sand or sand-layer sandwiched gravel), especially when the formation is in a super seismic zone, the above specifications are completely inapplicable.

In addition, the conventional method for carrying out vibroflotation gravel pile construction is not applicable to stratum with large thickness of a covering layer and frequent strong earthquake, particularly under the condition of easy occurrence of extra-large earthquake, because the conventional vibroflotation method cannot ensure the water permeability of the formed gravel pile and cannot ensure that the pile body is not broken under the condition of extra-large earthquake.

Disclosure of Invention

The invention aims to solve the problems, and provides a water permeability detection control method for construction of ultra-deep vibroflotation gravel piles of ultra-strong earthquake zones, which ensures that the ultra-deep vibroflotation gravel piles formed under ultra-deep overburden layers of the ultra-strong earthquake zones have good water permeability, are tightly combined with surrounding soil layers, can vertically upload deep ultra-quiet pore water pressure to gravel cushion layers under strong earthquake conditions, and ensures the safety of the vibroflotation gravel piles under strong earthquake.

In order to achieve the above purpose, the invention provides a water permeability detection control method for ultra-deep vibroflotation gravel pile construction of an ultra-strong seismic zone, comprising the following steps:

the vibroflotation construction of the broken stone pile hole is rapidly completed by controlling the water-gas linkage of the vibroflotation broken stone pile machine comprising the telescopic guide rod and the vibroflotation device;

after cleaning the gravel pile hole, putting the gravel filler into the gravel pile hole, and carrying out vibroflotation encryption construction on the gravel filler in the gravel pile hole by using a vibroflotation device;

During the vibroflotation encryption construction of the vibroflotation device on the gravel filler, the slurry density of the slurry positioned above the gravel filler level in the gravel pile hole is obtained;

and controlling the flow rate of the sewage supplied by the sewage and the flow rate of the sewage supplied by the sewage according to the obtained slurry density so that the vibroflotation device finishes vibroflotation encryption construction on the crushed stone filler under the synergistic effect of the sewage and the sewage, thereby forming the vibroflotation crushed stone pile which meets the water permeability requirement and has an effective pile diameter.

Wherein, obtain the mud density of the mud that lies in rubble filling material level above the rubble stake hole and include:

pumping the slurry above the crushed stone filler level in the crushed stone pile hole to a slurry densimeter by using a slurry pump;

and detecting the mud density of the pumped mud by a mud densimeter, and obtaining the current mud density value of the gravel pile hole above the gravel filler level.

Preferably, the mud densitometer is mounted on the surface.

Preferably, controlling the flow rate of the sewage supplied with the sewage and the flow rate of the sewage supplied with the down-draft according to the obtained mud density includes:

after the current mud density value positioned above the crushed stone filler level in the crushed stone pile hole is obtained, comparing the current mud density value with a preset mud density threshold value;

And controlling the flow rate of the sewage supplied by the sewage and the flow rate of the sewage supplied by the sewage according to the comparison result of the current mud density value and the preset mud density threshold value.

Preferably, controlling the flow rate of the sewage supplied to the sewage and the flow rate of the sewage supplied to the sewage according to the comparison result of the current mud density value and the preset mud density threshold value comprises:

when the comparison result is that the current mud density value is within a first threshold value of the preset mud density, controlling the vibroflotation device to finish vibroflotation encryption construction under the synergistic effect of the current flow rate of the discharging water and the current flow rate of the discharging water;

and when the current mud density value exceeds the preset mud density first threshold value, controlling the flow of the sewer water supplied by the sewer water and the flow of the sewer gas supplied by the sewer gas so that the mud density value is within the preset mud density first threshold value.

Preferably, when the comparison result is that the current mud density value exceeds the preset mud density first threshold value, controlling the flow rate of the sewer water to be supplied and the flow rate of the sewer gas to be supplied so that the mud density value is within the preset mud density first threshold value comprises:

if the current mud density value is larger than the upper limit value of the first preset mud density threshold and is within the second preset mud density threshold, controlling the discharge flow to be increased to 75-80% of the rated maximum discharge flow, and controlling the discharge air pressure to be unchanged until the mud density value is within the first preset mud density threshold;

If the current mud density value is greater than the upper limit value of the second preset mud density threshold and is within the third preset mud density threshold, controlling the lower water flow to be increased to 85-90% of the rated maximum lower water flow, and controlling the lower air flow to be increased to 85-90% of the rated maximum lower air flow until the mud density value is within the first preset mud density threshold;

and if the current mud density value is greater than the upper limit value of the third preset mud density threshold, controlling the lower water flow to be increased to the rated maximum lower water flow, and controlling the lower air flow to be increased to the rated maximum lower air flow until the mud density value is within the first preset mud density threshold.

Wherein, through controlling the aqueous vapor linkage that includes flexible guide arm and vibroflotation ware vibroflotation gravel stake machine, accomplish the vibroflotation construction in rubble stake hole fast and include:

controlling the discharge flow of the supplied sewage according to the current stratum compactness obtained in the vibroflotation construction process; and

controlling the down-gas pressure of the supplied down-gas according to the current stratum compactness obtained in the vibroflotation construction process;

the vibroflotation device completes vibroflotation construction of the broken stone pile hole under the synergistic effect of the drainage and the air supply by controlling the drainage flow of the drainage supplied by the vibroflotation broken stone pile machine and the air supply pressure of the drainage.

The method for obtaining the current stratum compactness in the vibroflotation construction process comprises the following steps of:

acquiring the current vibroflotation current of a vibroflotation device;

searching the formation compactness corresponding to the current vibroflotation current according to the preset corresponding relation between the vibroflotation current and the formation compactness;

and determining the found formation compactness as the current formation compactness.

Preferably, the controlling the flow of the discharged water for supplying the discharged water according to the current formation compactness obtained in the vibroflotation construction process includes:

acquiring the current sewage pressure of the supplied sewage;

searching a target launching pressure corresponding to the current formation compactness according to the corresponding relation between the preset launching pressure and the formation compactness;

and controlling the flow rate of the sewage supplied by the second water pump by comparing the current sewage pressure with the target sewage pressure, so that the current sewage pressure is positioned in the target sewage pressure range.

Preferably, the forming of the vibroflotation gravel pile with the effective pile diameter by vibroflotation encryption construction of the vibroflotation device comprises:

during the construction period of vibroflotation encryption by using a vibroflotation device, detecting real-time vibration signals of the vibroflotation device when the vibroflotation device vibroflotates the gravels filling material embedded in the soil layer around the gravels pile hole by using a pick-up arranged on the inner side of the vibroflotation device shell;

And controlling the vibroflotation of the vibroflotation device to the gravel pile according to the real-time vibration signal of the vibroflotation device detected by the pick-up device arranged on the inner side of the vibroflotation device shell, so that the vibroflotation device vibroflotates to fill the gravel filler in the gravel pile hole to form the pile diameter of the gravel pile equal to the effective pile diameter.

Compared with the prior art, the water permeability detection control method for construction of the ultra-deep vibroflotation gravel pile in the ultra-strong earthquake zone has the following advantages:

1. according to the method for detecting and controlling the water permeability of the ultra-deep vibroflotation gravel pile construction of the ultra-strong earthquake zone, the slurry density in the process of forming the gravel pile by vibroflotation construction is detected in real time, the water permeability of the formed gravel pile is ensured to meet the preset requirement, the ultra-static pore water pressure of the deep part of the stratum can be vertically uploaded along the gravel pile under the condition of an ultra-large earthquake (such as the condition of 8.5-9 grades), so that the accident of contusion of the gravel pile under the condition of strong earthquake is avoided, and the stability and the safety of the composite foundation formed by the gravel pile are improved.

2. When the drainage effect is not obvious for the deep and thick covered complex stratum, the invention respectively and accurately controls the supply quantity of the drainage pressure and the drainage pressure according to the compactness of different stratum so that the deep hole vibroflotation construction of the complex stratum can be successfully completed under the synergistic effect of the proper drainage pressure and the drainage pressure by the vibroflotation device, thereby solving the difficult problem of the deep and thick covered stratum vibroflotation construction of more than 50 m.

3. According to the invention, by accurately controlling the water pressure, the water pressure in the telescopic guide rod is always higher than the external mud pressure, so that external mud is prevented from entering the telescopic guide rod from a gap of the telescopic guide rod; and the current water feeding flow is controlled to be positioned in the target water feeding flow range in the vibroflotation construction process, and the air feeding pressure is controlled to be positioned in the target air feeding pressure range so as to remove a small amount of sand and stones entering the telescopic guide rod, so that the telescopic guide rod can freely stretch and retract under the actions of water feeding and air feeding, and the deep hole vibroflotation construction of the complex stratum based on the telescopic guide rod can be reliably carried out.

4. The method can enable the gravel pile and surrounding soil layers to be tightly combined together, and the pile diameter of the gravel pile really meets the design requirement.

The present invention will be described in detail with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of a water permeability detection control method for ultra-deep vibroflotation gravel pile construction in an ultra-strong seismic zone;

FIG. 2 is a schematic view of an vibroflotation gravel pile machine used in the present invention;

FIG. 3 is a schematic block diagram of a water-gas linkage control system of the vibroflotation gravel pile machine of the present invention;

FIG. 4 is a flow chart of a method of obtaining current formation compaction according to an embodiment of the present invention;

FIG. 5 is a flow chart of a method for controlling water supply, air supply, water discharge and air discharge according to an embodiment of the present invention;

FIG. 6 is a flow chart of a method for controlling the flow of the offal supplied to the sewer according to the current formation compaction obtained during vibroflotation construction in accordance with an embodiment of the present invention;

FIG. 7 is a flow chart of a method for controlling down-gas pressure of supplied down-gas according to current formation compactness obtained during vibroflotation construction in accordance with an embodiment of the present invention;

FIG. 8 is a flow chart of a method of controlling the flow of water to supply the water supply according to an embodiment of the present invention;

FIG. 9 is a flow chart of a method of controlling the upper pressure of an supplied upper gas according to an embodiment of the present invention;

FIG. 10 is a schematic view of the present invention with a pickup inside the vibroflotation housing;

FIG. 11 is a schematic diagram of an encryption control section of the present invention for controlling the encryption control of the ballast filler by the vibroflotation device;

fig. 12 is a flowchart of a first embodiment of the vibroflotation encryption control performed by the encryption control section in fig. 11;

fig. 13 is a flowchart of a second embodiment of vibration encryption control by the encryption control section in fig. 11;

FIG. 14 is a flow chart of the present invention for controlling mud density.

Detailed Description

As shown in fig. 1, a flow chart of a method for detecting and controlling water permeability in construction of ultra-deep vibroflotation gravel piles in ultra-strong earthquake zones is provided, and the method comprises the following steps:

Wherein the present invention is implemented during construction of an vibroflotation gravel pile machine, and fig. 2 shows a block diagram of a vibroflotation gravel pile machine 1000 used during construction of the present invention. As shown in fig. 2, the vibroflotation gravel pile machine 1000 includes a lifting device, a guide rod 10, a vibroflotation device 13 and an automatic feeding device.

Specifically, the hoisting device comprises a host machine of the vibroflotation gravel pile machine, a mast 11 connected with the host machine, and a main hoisting device arranged at the rear end of the host machine, wherein a guide rod 10 is hoisted through a steel wire rope of the main hoisting device and the mast 11, so that the guide rod is vertically arranged under the action of dead weight.

In addition, an automatic feeding device is arranged on the main machine, is arranged at the rear part of the main machine of the hoisting device and can be used as a counterweight of the main machine. The automatic feeding device comprises an air pipe winding device, a cable winding device and a water pipe winding device, and the three devices and the main winding device are arranged to synchronously feed.

The guide bar 10 has a connection section at the upper part for connection with the wire rope of the main winding device, a support section at the middle and a working section at the lower part for connection with the vibrator 13. The guide rod 10 is a telescopic guide rod, so that the axial length of the guide rod 10 can be adjusted to change the lowering or lifting position of the vibroflotation system relative to the ground. That is, the guide bar 10 has a plurality of layers of sleeves sequentially sleeved from inside to outside, the connecting section is a top layer sleeve, the working section is a bottom layer sleeve, and the supporting section comprises one or more layers of middle sleeves. Wherein, adjacent two-layer sleeve pipe can adopt prior art's connection structure to link together, can make adjacent two-layer sleeve pipe axial slip smooth, can prevent again that torsion from taking place each other. When the guide rod is in operation, the number and the length of the multi-layer sleeves in the guide rod can be determined according to the use requirement, for example, more than 4 layers of sleeves can be adopted, and the length of each layer of sleeve can be 18-25 meters (the length of the sleeve on the top layer can be longer). When the pile is used, the length of the multi-layer sleeve of the guide rod can be prolonged or shortened, and when the multi-layer sleeve of the telescopic guide rod is fully extended, the total length of the telescopic guide rod can reach 100 meters or even longer, so that the vibroflotation gravel pile machine can be used for vibroflotation and hole making of a stratum with the depth of more than 50 meters.

The vibroflotation gravel pile machine construction generally comprises 1) vibroflotation to form gravel pile holes, and 2) vibroflotation encryption of the gravel filled in the gravel pile holes by using a vibroflotation device to form gravel piles.

The invention forms the gravel pile hole by a control method for the launching of the vibroflotation gravel pile machine.

The invention is suitable for deep hole vibroflotation with complex stratum, and ensures the smooth progress of deep hole vibroflotation construction by automatically controlling the water supply and the air supply in the vibroflotation construction process and automatically controlling the water supply and the air supply according to the current stratum compactness.

As shown in fig. 5, the embodiment provides a water-gas linkage control method of an vibroflotation gravel pile machine, which includes:

s100, a pipeline for supplying water and air goes deep into the lower part of the telescopic guide rod from the top of the telescopic guide rod, so that the water and the air form water flow and air flow from bottom to top in the telescopic guide rod under the action of a baffle at the lower part of the telescopic guide rod and flow out from the top of the telescopic guide rod;

s101, enabling a pipeline for supplying the sewage to pass through a telescopic guide rod and a vibroflotation device and then extend out of the bottom end of the vibroflotation device, so that the sewage is sprayed out of the bottom end of the vibroflotation device to perform water flushing pre-damage on a stratum;

s102, enabling a pipeline for supplying the down gas to penetrate through the telescopic guide rod and extend out of the side wall of the bottom sleeve of the telescopic guide rod, so that the down gas is sprayed out of the bottom of the telescopic guide rod to perform gas-flushing pre-damage on a stratum;

S103, controlling the internal water pressure of the telescopic guide rod to be always larger than the external slurry pressure in the vibroflotation construction process so as to prevent external slurry from entering the telescopic guide rod from a gap of the telescopic guide rod; at the same time

S104, controlling water feeding flow for supplying water and air feeding pressure for supplying air feeding so as to remove a small amount of sand and stone entering the telescopic guide rod under the synergistic effect of the water feeding and the air feeding;

s105, controlling the discharge flow of the supplied sewage according to the current stratum compactness obtained in the vibroflotation construction process; and

s106, controlling the down-gas pressure of the supplied down-gas according to the current stratum compactness obtained in the vibroflotation construction process;

s107, controlling the flow rate of the sewage and the pressure of the sewage, so that the vibroflotation device completes vibroflotation construction under the synergistic effect of the sewage and the sewage.

The following describes the sewage control method of the present embodiment in detail with reference to the accompanying drawings.

As shown in fig. 4, obtaining the current formation compaction during the vibroflotation construction process includes:

s201, acquiring the current vibroflotation current of a vibroflotation device;

s202, searching the formation compactness corresponding to the current vibroflotation current according to the preset corresponding relation between the vibroflotation current and the formation compactness;

And S203, determining the found formation compactness as the current formation compactness.

As shown in fig. 3, the vibroflotation device 3 is connected with the controller 1 through the vibroflotation device frequency conversion cabinet 2, and the vibroflotation device frequency conversion cabinet 2 and the controller 1 are in wireless connection, or can be in wired connection.

In one implementation of this embodiment, when a stratum with a locally uniform distribution is encountered, the obtained instantaneous value of the vibroflotation current is stable, and S201 obtaining the current vibroflotation current of the vibroflotation device is achieved by: acquiring an instantaneous value of the vibroflotation current of the vibroflotation device; and determining the obtained instantaneous value of the vibroflotation current as the current vibroflotation current.

When the embodiment is implemented, the controller 1 acquires the vibroflotation current signal of the vibroflotation device 3 from the vibroflotation device frequency conversion cabinet 2, and determines the acquired vibroflotation current as the current vibroflotation current. Or, a current detection sensor (not shown in the figure) is arranged on a vibroflotation line of the vibroflotation frequency conversion cabinet 2 connected with the vibroflotation 3; when the vibroflotation device 3 is started, a vibroflotation current signal is generated by the current detection sensor, and the vibroflotation current signal is transmitted to the controller 1 in real time in a wired or wireless mode. The controller 1 determines the vibroflotation current transmitted from the current detection sensor in real time as the present vibroflotation current. The current detection sensor may be any sensor capable of detecting current in the prior art. Such as a current transformer.

In another implementation of this embodiment, when a formation with a locally unevenly distributed is encountered, the instantaneous value of the obtained vibroflotation current jumps greatly, and S201 obtains the current vibroflotation current of the vibroflotation device by: acquiring a plurality of instantaneous values of vibroflotation current of a vibroflotation device; carrying out average treatment on the obtained instantaneous values of the plurality of vibroflotation currents to obtain average vibroflotation currents; the average vibroflotation current is determined as the present vibroflotation current. And the interval time for acquiring the adjacent two instantaneous values of the vibroflotation current is equal. The method for carrying out average treatment on the obtained instantaneous values of the plurality of vibroflotation currents comprises the following steps: continuously obtaining n (n is more than or equal to 2) instantaneous values of the vibroflotation current, braiding the n instantaneous values of the vibroflotation current into a queue, adding the n instantaneous values of the vibroflotation current in the queue, and taking an average value; adding one instantaneous value of the vibroflotation current newly obtained each time into the tail of the queue, removing one instantaneous value of the vibroflotation current at the same time, forming a new queue, adding n instantaneous values of the vibroflotation current in the new queue, and taking an average value.

In the embodiment, the method of obtaining the instantaneous value of the vibroflotation current is the same as that of the previous embodiment. Specifically, a current average processing module is arranged in the controller, the controller obtains instantaneous values of the vibroflotation current from the vibroflotation frequency conversion cabinet 2 or the current detection sensor, and n (n is more than or equal to 2) instantaneous values of the vibroflotation current in the queue are subjected to average processing through the current average processing module, so that average vibroflotation current is obtained; the controller determines the average vibroflotation current as the present vibroflotation current.

S202, searching the formation compactness corresponding to the current vibroflotation current according to the preset corresponding relation between the vibroflotation current and the formation compactness; and S203, determining the found formation compactness as the current formation compactness. The specific implementation mode is as follows:

the corresponding relation between the vibroflotation current and the formation compactness is preset in the controller. The corresponding relation between the vibroflotation current and the formation compactness is obtained through a test, namely, before the formal construction, a test pile is firstly made on site, and the controller analyzes and determines the corresponding relation between the vibroflotation current and the formation compactness through a large amount of data obtained by the test pile.

In one implementation of this example, the correspondence between vibroflotation current and formation compaction is shown in table 1. The formation compactness is divided into three grades of soft, medium and hard, and the corresponding relation between the formation compactness and the vibroflotation current of different grades is obtained through field test data.

TABLE 1 correspondence between vibroflotation current and formation compaction

Vibroflotation current I	Formation solidity Dr
		I<0.3Ie	Soft and soft
0.3Ie≤I<0.8Ie	In (a)
		I≥0.8Ie	Hard

Here, ie shown in table 1 is the rated current of the vibrator.

After the controller obtains the current vibroflotation current, the formation compactness corresponding to the current vibroflotation current is determined as the current formation compactness through the lookup table 1. For example, when the controller 1 obtains the current vibroflotation current i=0.3 Ie, the current formation compaction is determined as a middle level by looking up table 1.

It should be noted that table 1 only shows one correspondence between vibroflotation current and formation compactness, and for more complex formations, the controller may also obtain other more complex correspondences according to field test data.

Wherein, S105 controls the flow of the sewer water to be supplied according to the current formation compactness obtained in the vibroflotation construction process, as shown in fig. 6, including:

s301, acquiring the current sewage pressure of the supplied sewage;

s302, searching a target launching pressure corresponding to the current formation compactness according to a preset corresponding relation between the launching pressure and the formation compactness;

s303, controlling the water discharge flow of the second water pump for supplying the water discharge by comparing the current water discharge pressure with the target water discharge pressure, so that the current water discharge pressure is positioned in the target water discharge pressure range.

The controller converts a difference signal between the current sewage pressure and the target sewage pressure into a control signal to control the sewage flow of the second water pump for supplying the sewage, so that the current sewage pressure is positioned in the target sewage pressure range.

In this embodiment, the plunger pump BW450 is used to supply the sewage, and other pumps may be used to supply the sewage, so long as the supplied sewage pressure and the supplied sewage flow meet the requirements.

Because the plunger pump water supply has the characteristics of larger fluctuation of the pulsating pressure and the instantaneous flow, the plunger pump water supply has the advantages that: s301 obtains a current sewage pressure of the supply sewage, including:

s401, acquiring a plurality of instantaneous sewage pressures for supplying sewage;

s402, carrying out average treatment on the instantaneous water pressures to obtain average water pressure;

and S403, determining the obtained average sewer pressure as the current sewer pressure.

Wherein, when a plurality of instantaneous water pressure of the supply sewage is obtained in S401, the interval time of obtaining the adjacent two instantaneous water pressures is equal.

In one implementation of this embodiment, S402 averages the plurality of instantaneous water pressures to obtain an average water pressure, which is specifically as follows: and forming a sampling interval by continuously acquiring n (n is more than or equal to 2) instantaneous downwater pressures, adding the n instantaneous downwater pressures in the sampling interval, and then taking an arithmetic average value.

In another implementation manner of this embodiment, S402 averages the plurality of instantaneous water pressures to obtain an average water pressure, which is specifically as follows: and forming a sampling interval by continuously acquiring n (n is more than or equal to 2) instantaneous water pressure, and solving the root mean square of the n instantaneous water pressure in the sampling interval.

In the two embodiments, the n instantaneous downwater pressures in the previous sampling interval are not overlapped with the n instantaneous downwater pressures in the next sampling interval. For example, the first sample interval contains the 1 st, 2 nd instantaneous downwater pressure, the second sample interval contains the 3 rd, 4 th instantaneous downwater pressure, and so on.

In the implementation of the above two embodiments, as shown in fig. 3, a second water supply pressure detection sensor 41 and a second water supply flow rate detection sensor 42 are installed on the water outlet pipe of the second water pump 4, and are respectively used for detecting the instantaneous sewage pressure and the instantaneous sewage flow rate of the sewage supplied by the second water pump 4 in real time. The second water supply pressure detection sensor 41 and the second water supply flow rate detection sensor 42 may employ any sensor capable of detecting water pressure and water flow rate in the related art. For example, the second water supply pressure detection sensor 41 may employ a pressure transmitter, and the second water supply flow rate detection sensor 42 may employ an electromagnetic flowmeter.

A pressure signal averaging circuit is added to the inside of the second water supply pressure detecting sensor 41 for averaging the n instantaneous downwater pressures continuously detected by the second water supply pressure detecting sensor 41 to obtain an average downwater pressure, and the controller 1 collects the average downwater pressure and determines the average downwater pressure as the current downwater pressure.

In addition, a flow signal averaging circuit is added inside the second water supply flow detection sensor 42, and is used for averaging the continuous n instantaneous water flows to obtain an average water flow rate, and the controller 1 determines the collected average water flow rate as the current water flow rate.

As shown in fig. 3, the second water supply pressure detection sensor 41 and the second water supply flow rate detection sensor 42 transmit the average sewage pressure signal and the average sewage flow rate signal to the remote terminal unit RTU, which transmits the signals to the controller 1 by wireless.

A pressure signal average processing module and a flow signal average processing module may be added in the controller, and the controller may perform an average process on the n instantaneous downwater pressures transmitted from the second water supply pressure detecting sensor 41 and an average process on the n instantaneous downwater flows transmitted from the second water supply flow detecting sensor 42, to obtain an average downwater pressure and an average downwater flow, respectively, and determine the average downwater pressure as the current downwater pressure and the average downwater flow as the current downwater flow.

S302, searching a target launching pressure corresponding to the current formation compactness according to a preset corresponding relation between the launching pressure and the formation compactness, wherein the specific implementation mode is as follows: the corresponding relation between the sewage pressure and the formation compactness is preset in the controller. The corresponding relation between the drainage pressure and the formation compactness is obtained through a test, namely, before the formal construction, a test pile is firstly made on site, and the controller analyzes and determines the corresponding relation between the drainage pressure and the formation compactness through a large amount of data obtained by the test pile.

In one implementation of this example, the correlation of the drainage pressure to formation compaction is shown in table 2. The formation compactness is divided into three grades of soft, medium and hard, and the corresponding relation between the formation compactness of different grades and the sewage pressure is obtained through field test data.

TABLE 2 correspondence between the downforce pressure and formation compaction

Downdraft pressure P (MPa)	Formation solidity Dr
		0.3～0.5	Soft and soft
0.5～0.7	In (a)
		0.7～0.8	Hard

The controller 1 finds a target sewage pressure corresponding to the current formation compactness by looking up the table 2. As shown in table 2, the lower and upper limits are set for the lower water pressure for each level of formation compaction. For example, when the controller 1 determines the current formation compactness as a middle level through the lookup table 1, the target sewage pressure corresponding to the middle level current formation compactness is found to be 0.5 to 0.7MPa through the lookup table 2.

It should be noted that table 2 only shows one correspondence between the pressure of the sewage and the formation compactness, and for more complex formations, the controller may also obtain other more complex correspondences according to the field test data.

Wherein, S303 controls the second pump to supply the water discharge flow of the water discharge by comparing the current water discharge pressure with the target water discharge pressure, so that the current water discharge pressure is located in the target water discharge pressure range, and the method specifically comprises: when the current sewage pressure is greater than the target sewage pressure upper limit, controlling the second water pump 4 to reduce the sewage flow; when the current sewage pressure is smaller than the lower limit of the target sewage pressure, the second water pump 4 is controlled to increase the sewage flow; when the current sewage pressure is within the target sewage pressure range, the second water pump 4 is controlled to maintain the sewage flow rate.

As shown in fig. 3, in this embodiment, the second water pump 4 is connected to the controller 1 through the second water pump variable frequency cabinet 5, and the second water pump variable frequency cabinet 5 and the controller 1 are connected wirelessly, or may be connected by a wire. The controller 1 controls the rotation speed of the second water pump 4 by controlling the second water pump variable frequency cabinet 5 to change the output frequency, so as to change the discharge flow of the second water pump 4 for supplying the discharge water, and when the discharge flow of the second water pump discharged from the water outlet pipeline is increased, the discharge water pressure is also increased; when the discharge flow rate of the second water pump water outlet pipeline is reduced, the discharge pressure is also reduced.

In the vibroflotation construction process, if only the drainage is supplied, the auxiliary supply of the drainage is carried out when the construction effect is not obvious.

The following describes the air control method in this embodiment in detail with reference to the drawings.

Wherein, S106 controls the down-gas pressure of the supplied down-gas according to the current formation compactness obtained in the vibroflotation construction process, as shown in fig. 7, including:

s501, acquiring the down-draft pressure of the supplied down-draft;

s502, searching a target barometric pressure corresponding to the current formation compactness according to a preset correspondence between barometric pressure and formation compactness;

s503, comparing the obtained down air pressure with the target down air pressure, and controlling the down air pressure of the second air compressor to supply down air, so that the obtained down air pressure is within the target down air pressure range.

The controller converts the acquired difference signal between the down air pressure and the target down air pressure into a control signal to control the down air pressure supplied by the second air compressor to be within the target down air pressure range.

The current formation compactness is obtained through the launch control method.

In this embodiment S501, the obtaining of the down-draft pressure of the supplied down-draft specifically includes: and detecting the instantaneous downward air pressure of the downward air supplied by the second air compressor in real time, and acquiring the instantaneous downward air pressure with equal interval time.

In one implementation of this embodiment, the method for obtaining the downdraft pressure is as follows:

as shown in fig. 3, a gas storage tank is disposed at the outlet of the second air compressor 8, and a second gas supply pressure detection sensor 81 is mounted on the gas outlet pipe of the gas storage tank for detecting the instantaneous downdraft pressure of the downdraft supplied from the second air compressor 8. The second air supply pressure detection sensor 81 may be any sensor capable of detecting air pressure in the related art. For example, a pressure transmitter may be employed.

In addition, a second air supply flow rate detection sensor 82 is installed on an air outlet pipe of the air tank of the second air compressor 8 for detecting the lower air flow rate of the lower air supplied from the second air compressor 8. The second supply air flow rate detection sensor 82 may be any sensor capable of detecting the amount of air flow in the related art. For example, a vortex shedding flowmeter may be employed.

The second air supply pressure detection sensor 81 and the second air supply flow rate detection sensor 82 transmit the detected pressure signal and flow rate signal to the remote terminal unit RTU, which transmits the signals to the controller 1 by wireless.

Wherein, S502 searches for a target down-gas pressure corresponding to the current formation compactness according to a preset relationship between the down-gas pressure and the formation compactness, and the specific implementation manner is as follows:

the controller is preset with the corresponding relation between the down-gas pressure and the formation compactness. The corresponding relation between the down-pressure and the formation compactness is obtained through a test, namely, before the formal construction, a test pile is firstly made on site, and the controller analyzes and determines the corresponding relation between the down-pressure and the formation compactness through a large amount of data obtained by the test pile.

In one implementation of this example, the relationship between barometric pressure and formation compaction is shown in table 3. The formation compactness is divided into three grades of soft, medium and hard, and the corresponding relation between the formation compactness of different grades and the down-pressure is obtained through field test data.

TABLE 3 correspondence between downdraft pressure and formation compaction

Down-draft pressure P (MPa)	Formation solidity Dr
		0	Soft and soft
0.3～0.5	In (a)
		0.7～0.8	Hard

The controller 1 finds a target barometric pressure corresponding to the current formation compaction by looking up table 3. As shown in table 3, the lower gas pressure for each level of formation compaction sets upper and lower limits. For example, when the controller 1 determines the current formation compactness as a middle level through the lookup table 1, the target downgas pressure corresponding to the middle level current formation compactness is found to be 0.3-0.5 MPa through the lookup table 3.

It should be noted that table 3 only shows one correspondence between the downdraft pressure and the formation compactness, and for more complex formations, the controller may also obtain other more complex correspondences according to the field test data.

Wherein, S503 controls the air pressure of the air supplied by the second air compressor by comparing the obtained air pressure with the target air pressure, so that the obtained air pressure is within the target air pressure range, and specifically includes:

when the acquired lower air pressure is greater than the upper limit of the target lower air pressure, controlling the second air compressor to reduce the lower air pressure; when the acquired lower air pressure is smaller than the lower limit of the target lower air pressure, controlling the second air compressor to increase the lower air pressure; and when the acquired lower air pressure is within the target lower air pressure range, controlling the second air compressor to maintain the lower air pressure.

In one implementation of this embodiment, as shown in fig. 3, a second electric control valve 9 is mounted on the air outlet pipe of the air tank, and the air pressure is controlled by controlling the valve opening of the second electric control valve 9. As shown in fig. 3, the controller 1 of the present embodiment transmits a valve opening signal to the remote terminal unit RTU by wireless, and controls the valve opening of the second electric control valve 9 by the RTU. When the valve of the second electric regulating valve 9 is opened, the lower air flow is increased, and the lower air pressure is also increased; when the valve of the second electric control valve 9 is opened, the lower air flow rate decreases, and the lower air pressure also decreases.

For the deep and covered complex stratum, the embodiment respectively and automatically controls the supply quantity of the lower water pressure and the lower air pressure according to the compactness of different strata, thereby smoothly completing deep hole vibroflotation construction by matching with a vibroflotation device.

Deep hole vibroflotation construction based on a telescopic guide rod needs to be matched with water supply.

The water supply control method of this embodiment will be described in detail with reference to the accompanying drawings.

Water supply control principle in this embodiment: 1. controlling the water pressure, controlling the water pressure in the telescopic guide rod to be always larger than the mud pressure of the pile hole, forcing the water in the telescopic guide rod to flow from the sleeve gap of the telescopic guide rod to mud in the pile hole, and realizing the water pressure dynamic balance in the pipe so as to prevent sand and stone in the mud from entering and being blocked in the sleeve gap; 2, controlling the water feeding flow, and in the process that the water feeding flows upwards from the top of the bottom sleeve to the top sleeve and then is discharged, keeping the water feeding flow in the telescopic guide rod at a certain level, so as to bring out a small amount of sand and stone which accidentally enters the telescopic guide rod, and avoiding being blocked in a sleeve gap.

Based on the principle, the water feeding flow is controlled in real time on the basis of guaranteeing the dynamic balance of the water pressure in the pipe, so that the pipe clamping can be avoided, and the purpose of freely stretching the stretching guide rod is achieved.

Wherein, S103 is in the shake-wash work progress, and the inside upper water pressure of control flexible guide arm is greater than outside mud pressure all the time, and concrete implementation is as follows:

the internal water pressure of the telescopic guide rod comprises the water pressure (ρ) _{Water and its preparation method} gh) and the water pressure (delta P) supplied by the first water pump, the internal water pressure of the telescopic guide rod is always larger than the external mud pressure, namely the telescopic guide rod is controlledInternal hydrostatic pressure (. Rho.) _{Water and its preparation method} gh) and the first water pump supply a water pressure (deltaP) which is greater than the mud pressure (ρ) in the outer pile hole of the telescopic guide rod _Pulp gh), i.e. the water supply pressure (deltap) of the first water pump is controlled to be greater than the mud pressure (ρ) in the outer pile hole of the telescopic guide rod _Pulp gh) and the hydrostatic pressure (ρ) in the telescopic guide rod _{Water and its preparation method} gh), i.e. ΔP > ρ _Pulp gh-ρ _{Water and its preparation method} gh。

Wherein ρ is _{Water and its preparation method} ＝1g/cm ³ ，ρ _Pulp ＝1.4g/cm ³ G is approximately 10m/s, and if h=100 m, ΔP > 0.4MPa.

According to the calculation, when the hole depth is 100m, the hydraulic dynamic balance in the telescopic guide rod can be kept by controlling the water pressure supplied by the first water pump to be greater than 0.4MPa, so that sand in mud is prevented from entering and being blocked in a sleeve gap.

In particular, the first water pump 6 may be a water pump with a minimum pump pressure of greater than 0.4MPa. For example, plunger pump BW320 is used with a minimum pump pressure of 1.5MPa.

Specifically, the internal water pressure of the telescopic guide rod is controlled to be always larger than the external slurry pressure, namely, the water pressure supplied by the first water pump is controlled to be realized in the following manner: acquiring the current water supply pressure of supply water; controlling the water supply pressure of the first water pump to supply water by comparing the current water supply pressure with the reference water supply pressure, so that the current water supply pressure is greater than or equal to the reference water supply pressure; wherein, the sum of the reference water pressure and the internal water pressure of the telescopic guide rod is always larger than the external mud pressure.

The specific embodiment of obtaining the current upper water pressure can be seen from the current lower water pressure. When the hole depth is 100m, the reference water pressure is 0.4MPa.

Under the condition that the current water supply pressure is larger than the reference water supply pressure, the embodiment brings out a small amount of sand and stone which accidentally enters the telescopic guide rod through controlling the water supply flow in real time, and the sand and stone are prevented from being clamped in a sleeve gap.

Wherein, S104 controls the flow rate of the water supply and, as shown in fig. 8, includes:

s601, acquiring the current water supply flow of the water supplied by a first water pump;

s602, controlling the water supply flow of the first water pump to supply water by comparing the current water supply flow with the target water supply flow, so that the current water supply flow is positioned in the range of the target water supply flow.

The controller converts a difference signal of the current water feeding flow and the target water feeding flow into a control signal, and controls the first water pump to supply the water feeding flow of the water feeding, so that the current water feeding flow is located in the range of the target water feeding flow.

Wherein, the specific implementation mode of obtaining the current water supply flow of the first water pump to supply water in S601 refers to obtaining the current water supply flow.

In this embodiment S602, by comparing the current water supply flow with the target water supply flow, the water supply flow of the first water pump is controlled, which specifically includes: when the current water feeding flow is larger than the upper limit of the target water feeding flow, controlling the first water pump 6 to reduce the water feeding flow; when the current water feeding flow is smaller than the lower limit of the target water feeding flow, the first water pump 6 is controlled to increase the water feeding flow; when the current water feed flow is within the target water feed flow range, the first water pump 6 is controlled to maintain the water feed flow.

In one implementation of the present example, the target upper water flow range is set to 280+ -10L/min. The maximum flow 320L/min of the plunger pump BW320 is greater than the target water flow. Other first water pumps 6 that meet the water supply requirements of the present embodiment are also selectable.

As shown in fig. 3, a first water supply pressure detection sensor 61 and a first water supply flow rate detection sensor 62 are installed on the water outlet pipe of the first water pump 6 for detecting the instantaneous water supply pressure and the instantaneous water supply flow rate of the water supplied from the first water pump 6 in real time, respectively. The first water supply pressure detection sensor 61 and the first water supply flow rate detection sensor 62 may employ any sensor capable of detecting water pressure and water flow rate in the related art. For example, the first water supply pressure detection sensor 61 may employ a pressure transmitter, and the first water supply flow rate detection sensor 62 may employ an electromagnetic flowmeter.

As shown in fig. 3, the first water pump 6 is connected with the controller 1 through the first water pump variable frequency cabinet 7, and the first water pump variable frequency cabinet 7 and the controller 1 are in wireless connection, or can be in wired connection. The controller 1 controls the rotation speed of the first water pump 6 by changing the output frequency of the first water pump variable frequency cabinet 7, so as to change the water feeding flow of the first water pump 6 for feeding water, and the current water feeding flow is positioned in the target water feeding flow range.

In one implementation manner of this embodiment, the plunger pump is used to supply the water, the method for obtaining the current water flow and the current water pressure by the controller 1 refers to the method for obtaining the current water flow and the current water pressure by the controller 1 by using the plunger pump to supply the water, and the method for obtaining the current water flow and the current water pressure by the controller 1 is not repeated.

Deep hole vibroflotation construction based on telescopic guide rod, if only supplying water, auxiliary supplying air when construction effect is not obvious.

Wherein, S104 controls the upper air pressure of the supplied upper air, as shown in fig. 9, including:

s701, obtaining the air supply pressure of the air supply of the first air compressor;

s702, controlling the upper air pressure of the upper air supplied by the first air compressor by comparing the acquired upper air pressure with the target upper air pressure, so that the acquired upper air pressure is within the target upper air pressure range.

Wherein, S701 obtains the upper air pressure of the upper air supplied by the first air compressor, which specifically includes: and detecting the instantaneous upper air pressure of the upper air supplied by the first air compressor in real time, and acquiring the instantaneous upper air pressure with equal interval time.

In one implementation of this embodiment, the method for obtaining the barometric pressure is as follows:

as shown in fig. 3, an air storage tank is arranged at the outlet of the first air compressor, and a first air supply pressure detection sensor is installed on the air outlet pipe of the air storage tank and used for detecting the instantaneous air supply pressure of the air supplied by the first air compressor. The first air supply pressure detection sensor may be any sensor capable of detecting air pressure in the related art. For example, a pressure transmitter may be employed.

In addition, a first air supply flow detection sensor is arranged on an air outlet pipeline of the air storage tank of the first air compressor and used for detecting the upper air flow of the upper air supplied by the first air compressor. The first supply air flow rate detection sensor may be any sensor capable of detecting the amount of air flow in the related art. For example, a vortex shedding flowmeter may be employed.

The first air supply pressure detection sensor and the first air supply flow detection sensor transmit the detected pressure signal and flow signal to the remote terminal unit RTU, which transmits the signals to the controller 1 by wireless.

The step S702 of comparing the obtained upper air pressure with the target upper air pressure, controlling the upper air pressure of the upper air supplied by the first air compressor to enable the obtained upper air pressure to be within the target upper air pressure range, and specifically includes:

when the acquired upper air pressure is greater than the upper limit of the target upper air pressure, controlling the first air compressor to reduce the upper air pressure; when the acquired upper air pressure is smaller than the lower limit of the target upper air pressure, controlling the first air compressor to increase the upper air pressure; and when the acquired upper air pressure is within the target upper air pressure range, controlling the first air compressor to maintain the upper air pressure.

In one embodiment of the present example, the target upper pressure range is set to 0.3 to 0.4MPa.

As shown in fig. 3, a first electric regulating valve is installed on an air outlet pipe of the air storage tank, and the air charging pressure is controlled by controlling the valve opening of the first electric regulating valve. As shown in fig. 3, the controller 1 of the present embodiment transmits a valve opening signal to the remote terminal unit RTU by wireless, and controls the valve opening of the first electric control valve by the RTU. When the valve of the first electric regulating valve is opened, the upper air flow is increased, and the upper air pressure is also increased; when the valve of the first electric regulating valve is opened, the upper air flow is reduced, and the upper air pressure is also reduced.

The embodiment adopts an SV-70 type vibroflotation gravel pile machine, a telescopic guide rod is connected with the vibroflotation device, and the water-gas linkage automatic control process is as follows:

1. after the vibroflotation device 3 is started, the second water supply pressure detection sensor 41 detects instantaneous water pressure in real time, the second water supply flow detection sensor 42 detects instantaneous water flow in real time, the second air supply pressure detection sensor 81 detects instantaneous air pressure in real time, the second air supply flow detection sensor 82 detects instantaneous air flow in real time, the first water supply pressure detection sensor 61 detects instantaneous water pressure in real time, the first water supply flow detection sensor 62 detects instantaneous water flow in real time, the first air supply pressure detection sensor detects instantaneous air pressure in real time, and the first air supply flow detection sensor detects instantaneous air flow in real time;

2. the controller 1 obtains current vibroflotation current, current water pressure, current water discharge flow, lower air pressure, lower air flow, current water pressure, current water discharge flow, upper air pressure and upper air flow;

3. the controller 1 determines the current formation compactness corresponding to the current vibroflotation current according to the obtained current vibroflotation current lookup table 1; determining a target sewage pressure corresponding to the current formation compactness through a lookup table 2; determining a target barometric pressure corresponding to the current formation compaction by looking up table 3;

4. The controller 1 compares the obtained current launching pressure with the target launching pressure which is determined by searching, converts the difference signal into a control signal to control the output frequency of the second water pump variable-frequency cabinet 5, and changes the launching flow of the second water pump 4 by controlling the rotating speed of the second water pump 4 so as to change the launching pressure, so that the current launching pressure is positioned in the target launching pressure range;

the controller 1 compares the obtained down-pressure with the target down-pressure determined by searching, and converts the difference signal into a control signal to control the valve opening of the second electric regulating valve 9, so as to change the down-pressure to enable the down-pressure to be in the target down-pressure range;

the controller 1 compares the obtained current water feeding flow with the target water feeding flow, converts the difference signal into a control signal to control the output frequency of the first water pump variable-frequency cabinet 7, and controls the rotation speed of the first water pump 6 to change, so that the current water feeding flow is positioned in the range of the target water feeding flow by the first water pump 6;

the controller 1 compares the acquired upper air pressure with the target upper air pressure, and converts the difference signal into a control signal to control the valve opening of the first electric regulating valve, so that the upper air pressure is changed, and the upper air pressure is located in the target upper air pressure range.

After the gravel pile hole is formed by adopting the method, the gravel filler is put into the gravel pile hole, and the gravel filler is subjected to vibroflotation encryption through a vibroflotation device so as to form the gravel pile. In the vibroflotation encryption process, the mud density of the mud above the crushed stone filler level in the crushed stone pile hole is detected by a mud pump so that the mud density in the pile hole meets the requirements.

Acquiring the mud density in the gravel pile hole in the hole cleaning process through a mud pump, comprising:

When the device is applied, the mud densimeter can be installed on the ground, such as the upper part of the outermost layer of the telescopic guide rod, or the mast, or the pile frame of the vibroflotation gravel pile machine, and the like. The mud pump can be arranged in the gravel pile hole through the winch device and is positioned 10 cm to 50cm above the top of the gravel filler material surface, and the mud above the gravel filler material surface is pumped to a mud densimeter positioned on the ground through a pipeline. Alternatively, the slurry pump and the slurry densimeter can be integrated and placed on the ground, such as being installed on the upper part of the outermost layer of the telescopic guide rod, or on a mast, or on a pile frame of a vibroflotation gravel pile machine, and then, a pipeline is sent into a gravel pile hole through a hoisting device, the lower end of the pipeline reaches the top of a gravel filler level, and the slurry above the extracted gravel filler level is pumped to the slurry densimeter positioned on the ground through the pipeline.

When the mud densimeter and the mud pump are installed, the mud densimeter and the mud pump can be connected with other parts in a detachable connection mode, so that the mud densimeter and the mud pump can be detached when the mud density does not need to be detected.

Wherein controlling the flow rate of the sewage supplied with the sewage and the flow rate of the sewage supplied with the down-draft according to the obtained mud density comprises:

Specifically, as shown in fig. 14, according to the comparison result of the current mud density value and the preset mud density threshold value, controlling the flow rate of the sewage supplied with the sewage and the flow rate of the sewage supplied with the sewage includes:

and when the comparison result is that the current mud density value exceeds the preset mud density first threshold value, controlling the flow of the sewer water supplied by the sewer water and the flow of the sewer gas supplied by the sewer gas so that the mud density value is within the preset mud density first threshold value, wherein the method comprises the following steps of:

The controller is preset with the corresponding relation between the slurry density in the gravel pile holes and the gravel piles with different water permeability. The corresponding relation between the mud density and the gravel piles with different water permeability is obtained through tests, namely, before the formal construction, the test piles are firstly made on site, and the controller analyzes and determines the corresponding relation between the mud density and the gravel piles with different water permeability through a large amount of data obtained by the test piles. The preset mud density threshold is a mud density value corresponding to the gravel pile with the water permeability meeting the preset requirement.

When the method is applied, the preset slurry density threshold value is determined according to the actual construction condition, and in the method, the first preset slurry density threshold value is [1.03-1.10g/cm < 3 >, the second preset slurry density threshold value is (1.10-1.12 g/cm < 3 >, and the third preset slurry density threshold value is (1.12-1.15 g/cm < 3 >).

And the rated maximum downflow are determined according to a vibroflotator and a water pump and an air pump adopted in the construction of the vibroflotation gravel pile machine. Wherein the current downflow, current downflow is typically 40-60% of the rated maximum downflow and 50% of the rated maximum downflow.

According to the invention, the slurry density in the gravel pile hole above the filler level in the gravel filler vibroflotation encryption process is controlled, so that the water permeability of the gravel pile formed by vibroflotation encryption construction can be ensured to meet the preset requirement, the gravel pile can vertically upload the hyperstatic pore water pressure in the deep part of the stratum to the gravel cushion layer under the strong shock condition, and the situation that the vibroflotation gravel pile is broken under the strong shock is ensured.

Under the synergistic effect of the regulated sewage and the air, the vibroflotation device performs vibroflotation encryption construction on the crushed stone filler so as to form the vibroflotation crushed stone pile which meets the water permeability requirement and has an effective pile diameter.

And in the process of vibroflotation encryption to form the vibroflotation gravel pile with effective pile diameter, the method further comprises:

detecting real-time vibration signals of the vibroflotation device when the vibroflotation device vibroflotates the gravels embedded in the soil layer around the gravels pile hole by using a pickup arranged on the inner side of the vibroflotation device shell during the vibroflotation of the vibroflotation device on the gravels around the vibroflotation device;

and controlling the vibroflotation of the gravel pile by the vibroflotation device according to the real-time vibration signal of the vibroflotation device detected by the pick-up device arranged on the inner side of the vibroflotation device shell, so that the pile diameter of the gravel pile formed by filling the gravels in the gravel pile holes by the vibroflotation device is equal to the effective pile diameter.

The effective pile diameter of the gravel pile is the pile diameter of the gravel pile formed in the gravel pile hole and tightly combined with soil layers around the hole. The effective pile diameter of the gravel pile has the following significance:

firstly, tightly combining gravel piles formed in gravel pile holes with soil layers around the holes;

secondly, the effective pile diameter of the gravel pile is the pile diameter of the gravel pile meeting the vibroflotation encryption requirement, so that the actual pile diameter is not required to be calculated in the vibroflotation construction process, and the vibroflotation construction process is quickened.

Fig. 10 shows a structure of the vibrator of the present invention, which is different from the conventional vibrator in that a pickup 1311 for picking up sound and a support bar 1312 for fixing the pickup 1311 are installed inside a housing 1308 of the vibrator, and the support bar 1312 is fixed to a housing of a motor 1304 through a through hole of a bearing housing for supporting a shaft 1306. The vibroflotation device 13 shown in fig. 10 further comprises a hanger 1301, a water pipe 1302, a cable 1303, a motor 1304, a coupling 1305, a shaft 1306, an eccentric weight 1307, a housing 1308, fins 1309, a sewer pipe 1310, and a pickup 1311.

After the gravel pile hole is formed, the vibroflotator begins to vibroflotate and encrypt the gravel packing by energizing the motor 1304. The filler in the encrypted section is extruded into the original stratum along the horizontal direction under the action of the exciting force of the vibroflotation device, the filler at the upper part falls down in slurry under the action of dead weight, and the height of the filler can be measured in real time. As the encryption process proceeds, several phenomena occur:

first, the encryption current gradually increases;

secondly, the exciting force at the shell of the vibroflotation device is increased;

thirdly, the amplitude of the vibroflotation device is reduced;

fourthly, the packing around the vibroflotation device is gradually compacted, and the vibroflotation gravel pile body which is approximately circumference-shaped and has the highest compactness in the vibration receiving range around the vibroflotation device and basically equivalent to the lateral pressure provided by the original stratum when reaching the periphery of the pile hole is gradually formed.

The prior art mainly controls the encryption of the crushed stone filler according to the encryption current of the motor 1304, but has the following four problems:

first, there is no direct relationship between physical and engineering implications and compactness. The encryption current is required to be determined through a test, and the compactness data of the pile body can be obtained approximately after the test. However, when the depth of the vibroflotation gravel pile reaches more than 70m and even reaches the level of hundred meters, the compactness data of the pile body cannot be obtained through a traditional test under the depth, so that the encryption current cannot be determined through experiments;

Secondly, different types of vibroflotation devices with different powers have different currents in different stratum;

thirdly, from engineering practice, even though the vibroflotation devices are of the same manufacturer and model, the idle current of the vibroflotation devices is greatly different;

fourth, in colder areas, the idle current is larger when the vibroflotation device is used initially; and as the engineering expands, the temperature of the vibroflotation device per se increases, and the no-load current decreases.

Therefore, the pile compactness under the ultra-deep overburden condition cannot be represented by taking the encryption current as the compactness.

In order to solve the above problems in the prior art, the present invention proposes a technique for controlling the vibroflotation encryption (i.e., vibroflotation of the crushed stone filler) of the vibroflotation device according to the frequency of the vibration signal of the vibroflotation device when the vibroflotation device vibroflotates the crushed stone filler. The core technology of the encryption technology is as follows:

in the process of vibroflotation of the vibroflotation device 13 on the surrounding broken stone filler, a pickup arranged on the inner side of a vibroflotation device shell is used for detecting a vibroflotation device real-time vibration signal when the vibroflotation device vibroflotates broken stone embedded in a soil layer around a broken stone pile hole;

According to the real-time vibration signal of the vibroflotation device detected by the sound pickup 1311 arranged on the inner side of the vibroflotation device shell, the control of the vibroflotation device on the vibroflotation of the gravel pile comprises the following steps:

the real-time vibration signal of the vibrator is detected by the pickup to be converted from a time domain to a frequency domain, so that the main frequency of the real-time vibration signal of the vibrator is obtained;

comparing the main frequency of the real-time vibration signal of the vibroflotation device with a preset frequency;

when the main frequency of the real-time vibration signal of the vibroflotation device reaches or is close to the preset frequency, judging that the pile diameter of the crushed stone pile to be formed is equal to the effective pile diameter, and lifting the vibroflotation device upwards to vibroflotate crushed stone in the middle part of the crushed stone pile to be formed, so that the crushed stone pile with the pile diameter equal to the effective pile diameter is finally formed;

when the main frequency of the real-time vibration signal of the vibroflotation device is larger than the preset frequency, the vibroflotation device is controlled to continuously vibroflotate the gravels embedded in the soil layer around the gravel pile hole.

The preset frequency of the invention is the main frequency of the vibrator vibration signal obtained in advance when the amplitude of the vibrator is reduced to the minimum.

According to the real-time vibration signal of the vibroflotation device detected by the pickup arranged on the inner side of the vibroflotation device shell, the control of the vibroflotation device on the vibroflotation of the gravel pile comprises the following steps:

The method comprises the steps that the front vibroflotation vibration signal detected by the pickup in front and the rear vibroflotation vibration signal detected by the pickup in rear are subjected to time domain to frequency domain conversion, so that the main frequency of the front vibroflotation vibration signal and the main frequency of the rear vibroflotation vibration signal are obtained;

analyzing the main frequency of the vibration signal of the front vibrator and the main frequency of the vibration signal of the rear vibrator obtained in the vibration punching period;

when the main frequency of the vibration signal of the rear vibroflotator is smaller than that of the vibration signal of the front vibroflotator and is kept for a period of time, the pile diameter of the crushed stone pile to be formed is judged to be equal to the effective pile diameter, and the vibroflotator is lifted upwards to carry out vibroflotation on crushed stone in the middle part of the vibroflotation crushed stone pile to be formed, so that the crushed stone pile with the pile diameter equal to the effective pile diameter is finally formed.

The pickup provided inside the vibroflotation housing of the present invention includes a sound sensor and an audio amplifier.

The pickup provided inside the vibroflotation housing of the present invention may be a sound sensor.

Fig. 11 shows a control section for controlling vibroflotation of a vibroflotation filler, comprising a sound pickup 1311 for converting a vibration signal on a housing of the vibroflotation filler into a corresponding electric signal, an audio analysis module for audio analysis of the electric signal output from the sound pickup 1311, a processor for processing audio output from the audio analysis module, a memory for storing data output from the processor, and a display for displaying data output from the processor.

The processor is further connected to a main hoisting device to lift the vibroflotation device 13 upwards when it is determined that the diameter of the gravel pile to be formed is equal to the effective pile diameter.

The sound pickup 1311 of the present invention may include a sound sensor and an audio amplifier, or may include only a sound sensor.

The audio analysis module, processor, memory and display of the present invention may be located on the ground and the audio analysis module may be connected to the microphone by a cable. In addition, the audio analysis module of the present invention may be a fourier transformer that converts the vibration signal from the time domain to the frequency domain.

Compared with another patent application of the pressure sensor arranged on the vibrator outer shell, the service life of the sound sensor can be greatly prolonged. That is, since the sound sensor 1311 is installed inside the vibrator housing, it is not pressed by the crushed stone packing and the vibrator like the pressure sensor installed on the vibrator housing, and thus is not easily damaged.

Fig. 12 shows a control flow of the first embodiment of controlling the vibroflotation device to perform vibration encryption control, which is mainly implemented by a processor, and specifically includes:

Step S301, during the vibration impact of the vibration impact device on the crushed stone filler, detecting real-time vibration signals of a vibration impact device shell by a sound pickup;

step S302, performing time domain to frequency domain conversion on the real-time vibration signal of the vibroflotation device detected by the pickup to obtain the main frequency of the real-time vibration signal of the vibroflotation device

Step S303, judging whether the main frequency of the real-time vibration signal of the vibroflotation device reaches or approaches to a preset frequency;

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

step S305, lifting the vibroflotator upwards, and vibroflotating broken stone in the middle part of the vibroflotation broken stone pile to be formed, so that the broken stone pile with the pile diameter equal to the effective pile diameter is finally formed;

and step S306, when the judgment result of the step S302 is negative, controlling the vibroflotator to continuously vibroflotate the gravels embedded in the soil layer around the gravel pile hole.

Fig. 13 shows a control flow of a second embodiment of controlling a vibroflotation device to perform vibration encryption control, including:

step S401, detecting real-time vibration signals of a vibrator shell through a sound pick-up during the vibration of the broken stone filler by the vibrator, and obtaining a front vibrator vibration signal detected by the sound pick-up before and a rear vibrator vibration signal detected by the sound pick-up after;

Step S402, converting the time domain to the frequency domain of a front vibroflotation signal detected by the pickup and a rear vibroflotation signal detected by the pickup, so as to obtain a main frequency of the front vibroflotation signal and a main frequency of the rear vibroflotation signal;

step S403, judging whether the main frequency of the vibration signal of the rear vibrator is smaller than that of the vibration signal of the front vibrator;

step S404, if the judgment result of the step S403 is yes, further judging whether the main frequency of the vibrator vibration signal detected later is kept unchanged in a period of time;

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

step S405, lifting the vibroflotator upwards, and vibroflotating broken stone in the middle part of the vibroflotation broken stone pile to be formed, so as to finally form the broken stone pile with the pile diameter being greater than or equal to the effective pile diameter;

step S406, if the judgment result of step S403 or step S404 is no, controlling the vibroflotation device to continuously vibroflotate the gravels embedded in the soil layer around the gravel pile hole.

It should be pointed out that one of the characteristics of the invention is to provide a concept of effective pile diameter, namely the pile diameter of the gravel pile which is formed in the gravel pile hole, is tightly combined with soil layers around the hole and meets the vibroflotation encryption requirement.

The effective pile diameter of the gravel pile solves the technical problem that the gravel pile possibly existing in the prior art cannot be tightly combined with a soil layer.

Although the present invention has been described in detail, the present invention is not limited thereto, and those skilled in the art can make modifications according to the principles of the present invention, and thus, all modifications made according to the principles of the present invention should be construed as falling within the scope of the present invention.

Claims

1. A water permeability detection control method for ultra-deep vibroflotation gravel pile construction of an ultra-strong seismic zone comprises the following steps:

2. The method of claim 1, obtaining a mud density of mud above a gravel packing level within a gravel pile hole comprising:

3. The method of claim 2, the mud densitometer being mounted on the surface.

4. A method according to claim 2 or 3, controlling the flow of the downwater supplied to the downcomer and the flow of the downgas supplied to the downcomer in dependence on the obtained mud density comprising:

5. The method of claim 4, wherein controlling the flow rate of the downwater supplied to the sewage and the flow rate of the downgas supplied to the sewage based on a comparison of the current mud density value and a preset mud density threshold value comprises:

6. The method of claim 5, wherein controlling the flow of the downwater to the downwater supply and the flow of the downgas to the downgas supply such that the slurry density value is within the preset slurry density first threshold when the current slurry density value exceeds the preset slurry density first threshold as a result of the comparison comprises:

7. The method of claim 1, wherein the rapid completion of the vibroflotation construction of the gravel pile hole by controlling the water-air linkage of the vibroflotation gravel pile machine comprising the telescopic guide rod and the vibroflotation device comprises:

8. The method of claim 7, obtaining a current formation compaction during vibroflotation comprises:

acquiring the current vibroflotation current of a vibroflotation device;

9. The method of claim 8, the controlling the flow of the offal of the supply offal according to the current formation compaction obtained during the vibroflotation process comprising:

acquiring the current sewage pressure of the supplied sewage;

10. The method of claim 1, forming vibroflotation gravel piles having effective pile diameters using vibroflotation encryption construction comprising: