JPH0811889B2 - Support lining layer construction method and its equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a support lining layer constructed for the purpose of improving soft ground, particularly seabed ground, foundation of structures, and ground support during tunnel excavation. The present invention relates to the construction method and its equipment.

(Prior Art) In the high-pressure injection injection method which has been conventionally used for forming the support lining layer, the hardening material injection nozzle is opened in a direction perpendicular to the injection rod, and the unit hardening layers are formed in parallel. Is a columnar hardened layer, and the discharge of slime has mainly been performed by using a gap with the ground around the insertion rod, or by separately providing a casing with holes.

When using the gap between the ground around the insertion rod and the ground, there is no problem if the depth is shallow and the injection volume per minute is small, but the performance of the high-pressure pump has improved and a large amount of high-pressure injection is now available. Then, when the discharge is suppressed, it is compressed by the subsequent injection pressure, and a large amount of excess slime that increases the repulsive force near the nozzle is generated.

Especially in the case of improvement of the seabed, excess slime overflows from the injection rod insertion gap and diffuses into seawater, causing pollution problems.

Further, in the case where the casing is separately drilled, the cost increases due to double drilling as the depth increases, and the same adverse effects as when using the void with the ground around the insertion rod occur. There is no such thing. Others As a countermeasure against this excess slime, collection with a suction pump from the injection rod insertion port has been proposed, other than installing a packer or casing at the injection rod insertion port to push it back into the ground or overflow it to the ground and drip. There is only correspondence of whether or not it is thrown.

Further, in the case of pressure injection, no special consideration was given to the balance between the injection amount of the hardening material and the particle density of the ground.

On the other hand, the high-pressure injection injection method is also used to create the support lining layer for tunnel excavation, but since it is excavated in the horizontal direction, there is no room for the air etc. to rise and it is impossible to process slime and air. Reliable only on hardener injection, and efficient air injection was never used.

(Problems to be solved by the invention) The conventional curing material injection nozzle opens in a direction perpendicular to the injection rod, and the excess slime pressure around it is, so to speak, a state of leaving it to a certain extent, so that discharge is performed smoothly. If not, of course, the pressure around the injection nozzle rises, which not only reduces the injection performance, but when the pressure around the nozzle exceeds the air pressure of the injection air, it will stop blowing air, and the injection effect will be extremely extreme. Be reduced to. Further, when the slime pressure rises, there is a problem that not only the ground improvement effect is reduced, but also the ground is raised, and serious obstacles such as backflow of slime from the air ejection port occur.

Because of this problem, simple support with a diameter of 60 cm to 80 cm is used to create the support lining for tunnel excavation in the horizontal direction.
It was not possible to use it, though it was known that an injection diameter of ~ 3m50cm could be obtained.

In addition, since the unit hardening layers arranged in parallel have a columnar shape, there is a problem that the hardening material has to be wastefully injected to the excavated portion which is not necessary as the support lining layer.

(Means for Solving Problems) According to the present invention, a slime suction hole is provided in an injection rod, a hardening material injection nozzle is opened by inclining in a direction of excavation of the injection rod, and an injection rod is inserted into a rear portion of the slime suction hole. By providing an injection nozzle for fresh water such as packer that packs holes, the injection energy of the hardening material is diffused in the rod advancing direction to reduce the generation of slime and the generated slime is sucked into the suction hole provided in the injection rod itself. Then
The purpose of the present invention is to improve the injection effect by discharging from the suction hole through the discharge route in the injection rod, and to perform slime treatment all at once to improve workability and solve the problems from both aspects of the injection effect. Further, a packer for spraying fresh water or the like is provided at the rear portion of the suction hole so that the slime can be completely prevented from leaking and collected in the suction hole.

(Function) Slime generated by injection injection of ground hardening material is
The injection pressure due to the subsequent injection is compressed, and the internal pressure is gradually increased to accumulate the internal pressure energy. This internal pressure energy acts as an expansion force and acts as an external pressure on the injection rod, so if the injection rod is provided with an opening, the slime naturally flows into the opening to release the internal pressure. By this mechanism, when excess slime is sucked from the hardening material injection nozzle into the opening, that is, the suction hole provided at a predetermined interval, the burden of the hardening material injection pressure and the injection air applied to the rising force of the slime is reduced. However, since the porosity is also increased, the reaching distance of the jetted hardener jet is extended. On the other hand, when the internal pressure energy accumulated in the excess slime is released by inhaling slime into the inhalation hole, the amount of inhaled slime in the inhalation hole decreases in proportion to the decrease in the accumulated energy, and the hardener injection layer due to excessive suction The slimming phenomenon is automatically avoided.

In the present invention according to claim (2), since the hardening material injection nozzle is opened by inclining in the injection rod excavating direction, the hardening material is injected into the property while forming the top part into a gentle conical slope. However, since the injection direction is directed away from the slime intake hole, the effect of the presence of the slime intake hole on the injection energy is minimized, and the hardened material injected at an angle is sucked into the intake hole. In addition to avoiding this, the leak of hardened material is completely prevented in the case of seabed ground improvement.

Furthermore, if the rod insertion hole is packed by spraying fresh water or the like from the spray nozzle above the suction hole, air removal by the suction hole and slime backflow prevention by the pack are performed synergistically. The combined use of air can also be used for forming the injection layer in the horizontal direction.

In addition, the appropriate distance between the injection nozzle and the suction hole depends on the diameter of the injection rod, the type of hardening material, and the injection pressure, but if the appropriate distance can be adjusted, it will be extremely effective due to the synergistic effect of injection and suction. Injection can be performed.

According to the present invention of claim (4), the rotation of the injection rod at the time of injection of the curing material is rotated half a turn to the support layer side with the excavation side as a fulcrum, and columnar hardened layers having a semicircular or fan-shaped cross section are arranged in parallel. Create a continuous support liner layer by adding a hardened layer with a semi-circular or fan-shaped cross section in which the fulcrum is shifted to the support layer side and the hardened material is sprayed to the open / close side, if necessary. It is only half that of a cylinder, which makes it easy to excavate during excavation.

(Examples) Examples of the present invention will be described below with reference to the drawings. 1 is an injection rod, which is supported by the operating mechanism 2 and is lowered, raised,
Operation such as rotation or reciprocating reciprocating by an arbitrary set angle set by the setter 21 is given. The injection rod 1 may be a circular tube or a square tube, and a side wall of the tip end thereof is provided with a superposition injection nozzle 3 that is inclined and opened in the injection rod excavation direction. 31, surrounding nozzle 32, each opening of suction hole 5,
Multiple paths a, each opening to a packer nozzle,
It has b, c, d and e.

The polymerization injection nozzle 3 injects the hardening material, the air, and the fresh water, if necessary, supplied through the swivel 9 into the ground through the nuclear nozzle 31 or the surrounding nozzle 32 opening from different paths.

A transducer 81 molded with an ultrasonic wave transmitting element and an ultrasonic wave receiving element and a pressure sensor 82 are installed in the hardening material pressure feeding path 7 of the injection rod, and are connected to the counter system by a cable.

Reference numeral 5 is a suction hole, which is opened at a predetermined interval above the superposition injection nozzle 3 (in the case of a horizontal hole, it becomes a rear part), and excess slime produced by the injection operation from the injection nozzle 3 is utilized by utilizing its internal pressure energy. Inhale and deliver to filter press 6. A polymerization injection nozzle 52 for injecting an air jet or a mixed air jet of fresh water and air in the discharge direction is opened on the inner wall of the discharge path 51 in which the suction hole is opened. Although the superposition injection nozzle is effective for this mixed air jet discharge structure, collision injection or parallel injection may be used.

A packer nozzle 4 for injecting fresh water or the like is opened at an upper portion (in the case of a horizontal hole, a rear portion) of the suction hole 5, and a jet curtain is stretched to prevent rise of slime and backflow.

The filter press 6 is a filter dehydration chamber composed of a filter frame 61 and a peeling plate 62 which are arranged in an openable and closable manner, a support frame 63 for supporting the filter frame and the peeling plate, and an opening and closing frame 67 for operating the filter frame to open and close the filter frame. It consists of an operating unit consisting of a shearing unit 64 and a feeding unit 65.
The mud slime sent from the tank is filled in the filtration / dehydration chamber closed by the water supply pressure, and only the filtered water filtered through the filter cloth 68 flows through and is discharged from the drainage section 66 to be injected again as fresh water injection water, etc. Is supplied to. Filter press 6 is 7kg / cm
^{Although the} filtration action is automatically performed with a flow pressure of about ^{2, in} the case of the present invention, since a suction action is involved, it is effective to systemize with a stronger one.

The dewatered sludge is caked and peeled off by the peeling plate from the filter frame that is opened periodically by the operation of the shaft 64 and falls.

Using the device system as described above, the injection rod 1 is propelled and inserted into the target ground by an appropriate means such as rotation.

At a predetermined depth, the ground hardening material is applied from the core nozzle 31 of the superposition injection nozzle 3 to a high pressure of about 200 kgf / cm ² and a flow rate of 100 / mi.
Inject around before and after n, inject air from the surrounding nozzle 32 (in some cases, provide a surrounding nozzle further surrounding the outside of the surrounding nozzle 32 and inject fresh water from the surrounding nozzle) and packer nozzle While injecting fresh water or the like from 4, the injection rod 1 is reciprocally rotated by half a turn within an angle range set to a predetermined angle, and when it is retracted, the muddy water slime that has lost the crushing force due to the injection and becomes saturated is the slime due to the subsequent injection. When the internal pressure energy accumulated in itself raises or backflows, it is sucked from the suction hole 5 which is the only escape area, and further, when the mixed jet is injected from the superposition injection nozzle 51 opening to the discharge path 52, it is sucked. The slime is accelerated and sent to the filter press 6 through the discharge path 52.

Further, the slime that escapes from the suction hole 5 is prevented from rising or backflow by the curtain stretched by the packer nozzle 4 and eventually sucked into the negative pressure of the suction hole 5.

In this way, the density of the hardening material injected from the polymerization injection nozzle 3 under high pressure is adjusted by inhaling slime, and the soil around which the porosity is increased is mixed by stirring to form a ground hardening material injection layer in a semicircular or fan-shaped cross section. To go. During this time, the ultrasonic wave transmission by the transducer 81 and the flow rate measurement by the pressure sensor 82 installed in the hardening material pressure feed path 7 are captured by the counter system on the ground, and the injection management from the ground is performed.

Since the columnar hardened layer X has an arcuate side surface, the columnar hardened layer X is not completely polymerized due to the parallel arrangement, and a blank portion often occurs. In such a case, the injection rod is inserted with the excavation side P, which requires particularly precise continuity, as a fulcrum, and the curing material is injected toward the support layer side R so that the hardened layers having a semicircular cross section or a fan shape are arranged in parallel. Created, and if necessary, this time, shift the fulcrum to the support layer side R of the blank part and inject the curing material toward the excavation side P, and supplementarily combine the semi-circular cross-section or fan-shaped columnar hardened layers as a continuous support. Create a lining layer.

Further, in the case of forming a supporting lining layer in a horizontal direction such as a tunnel, the injection hardening material is biased to the lower side and a void S is generated on the upper side,
Since air or the like is accumulated, injection is sequentially performed from the lower side, and when injecting the uppermost hardening material, the fulcrum is shifted to the support layer side R and the hardening material is injected toward the cutting and cutting side P. By doing so, an escape area can be created in the air or the like due to a change in the injection position, and a supporting lining layer with a reliable structure can be created.

In addition, if the liquid A is injected from the core nozzle and the liquid B is injected from the surrounding nozzle as an instantaneous mixing structure for the curing material, the both liquids are mixed and reacted at the injection port to form an instantaneous injection layer to cure the liquid. It is possible to deal with urgent situations.

(Effects of the Invention) Since the present invention is configured as described above, the muddy water sludge that diminishes the injection effect and is a cause of pollution is suctioned and removed in the immediate vicinity of the injection nozzle, and at the same time, the diffusion of seawater such as a hardening material has been prevented. Improvement of the seabed ground that could not be adopted due to danger,
Since it is difficult to treat slime and air, only high-pressure injection can be used to create a tunnel support lining that could only be used for simple injection.

Further, by controlling the injection from the ground, the injection pressure can be made effective and the reaching distance of the hardening material jet can be extended to form a high-purity hardened material injection layer of large diameter. Further, the muddy water sludge can be treated at the same time, which has the effect of increasing efficiency in terms of both work and cost.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 is an overall explanatory view showing a construction situation, FIG. 2 is an enlarged vertical sectional view of a tip portion of an injection rod, and FIG. 3 shows a setting situation of a rotation angle. FIG. 4 is a plan view of the operating structure in which the injection rod portion is shown in section, FIG. 4 is an explanatory view showing the condition of the injection fulcrum and the injection direction in the case of horizontal injection, and FIG. 5 is an explanatory view showing the opening / closing condition of the filter press. Similarly, FIG. 7 is a side view of the filter press showing the relationship between the filter frame and the open / close frame half by half, and FIG. 7 is a cross-sectional view of the hardening material pressure-feeding path 7 showing the installation state of the transducer. 1-injection rod, 2-operation mechanism, 21-setter, 22-switch, 3-polymerization injection nozzle, 31-nuclear nozzle, 32-
Surrounding nozzle, 4-packer nozzle, 5-suction hole, 51-polymerization injection nozzle, 52-discharge path, 6-filter press,
61-filter frame, 62-release plate, 63-support frame, 64-shaft, 65
-Inlet part, 66-drainage part, 67-opening / closing frame, 68-filter cloth, 7-curing material pressure feed path, 81-transducer, 82-pressure sensor, 9-swivel, A-ultrasonic transmitting element, B -Ultrasonic receiving element, P-cutting side, R-support layer side, X-unit hardening layer, S-void, abcde-multiple separation path

Claims (6)

[Claims] 1. A superposition injection nozzle is provided on a side wall of a tip end portion of an injection rod having a multi-division path, and an injection rod having a slime suction hole opened at a position spaced from the injection nozzle is inserted into a target ground. While injecting the ground hardening material at high pressure from the core nozzle of the polymerization injection nozzle and air from the surrounding nozzle, while sucking muddy water slime generated at the time of injection into the above-mentioned suction hole, while moving the injection rod, it is withdrawn and moved. The columnar hardened layer is formed by injecting the ground hardened material with pressure by the method, and the columnar hardened layer is sequentially formed in parallel to form the supportive lining layer. 2. A support lining according to claim 1, wherein the superposition injection nozzle provided on the side wall of the tip end portion of the injection rod is inclined in the excavation direction of the injection rod to inject the hardening material in the excavation direction. Layer construction method 3. An injection nozzle is provided at a position further apart from the slime suction hole by a predetermined distance to inject the hardening material and inhale the muddy water slime, and at the same time, injecting fresh water or the like to remove escape slime accompanying the injection of the hardening material. Supporting lining layer construction method according to claims (1) and (2), which is configured to be packed 4. The rotation of the injection rod at the time of injection of the hardening material is a half-rotation reciprocating rotation to the support layer side with the cutting side as a fulcrum, and a column-shaped hardening layer having a semicircular or fan-shaped cross section is formed in parallel and supported as required. A continuous supporting lining layer is formed by adding a columnar hardened layer having a semicircular or fan-shaped cross section in which a fulcrum is shifted to the layer side and a hardening material is sprayed to the excavation side.
(2) Supporting lining layer construction method described in (3) 5. A polymerization injection nozzle, which is supported by an injection rod rotation mechanism and a forward / backward movement mechanism, is provided on a side wall of a tip end portion of an injection rod having a multi-divided path with an inclined opening so as to inject a hardening material in the digging direction. A supporting lining layer forming apparatus characterized in that a slime suction hole is opened at a position spaced from the injection nozzle by a predetermined distance. 6. A support cover layer forming apparatus according to claim 5, wherein a packer nozzle for injecting fresh water or the like is opened at a portion further spaced from the slime suction hole by a predetermined distance.