JPH0214489B2 - - Google Patents

Description

Detailed Description of the Invention (Object of the Invention/Field of Industrial Application) The present invention is used in the field of improving soft ground.

The present invention is used in the so-called sand compaction pile construction method or sand drain construction method, in which a casing is driven into soft ground to a predetermined depth, sand is poured into the casing, and compressed air is supplied into the casing. This invention relates to a device for constructing sand piles by pressing and pulling sand into the ground.

(Prior art and its problems) In this type of sand pile construction equipment, the on-off valve is generally provided only at one location on the top of the casing, so while compressed air is being supplied into the casing to push out the sand. If sand cannot be supplied into the casing and a certain amount of sand is to be supplied into the casing after this extrusion operation, the hopper is moved back and forth several times along the leader to feed the sand into the bucket. Because of this necessity, a considerable amount of time is also spent on this sand supply operation, which inevitably delays the next compressed air supply and sand extrusion operation.

Therefore, in order to eliminate such inconvenience,
An upper air valve and a lower air valve which are opened and closed by valve opening/closing drive means are provided at two upper parts of the casing, and a sand stock space and a lower air valve are provided between the upper and lower air valves. Japanese Patent Laid-Open No. 49-67407 discloses a sand pile construction device in which compressed air is supplied to each of the sand pressing spaces formed below by means of compressed air supply means. For example, the space between the upper air valve and the lower air valve is used as a sand storage space, and while the compressed air is supplied and the sand is pressed and pushed out by the air pressure, sand is filled into this storage space. Since the compressed air supply work and the sand charging work can be performed at the same time, the work time can be shortened, and the sand stored in the sand storage space can be transferred to the sand pressing space below. Since the sand is dropped into the chamber using compressed air, the sand can be charged quickly and reliably without causing sand clogging.

However, in the conventional sand pile construction device described in the above-mentioned patent publication, air valves are provided at the top and bottom of the sand supply hopper connected to the top of the casing, and the entire inside of the casing itself is pressed with sand. Because of this, the amount of compressed air to be supplied for sand pressing is extremely large, and it takes a considerable amount of time to supply the compressed air. In addition, each air valve has one end of the valve body pivotally connected to the hopper side, and the other end pivotally connected to the piston rod of a fluid pressure cylinder serving as a driving means. It is necessary to insert the piston rod inside the hopper, and even if the piston rod does not hit sand or crushed stones, sand particles or dust may adhere to the piston rod and enter the inside of the cylinder, or the sliding part of the rod may There is a risk of injury. Also, if an air valve with the above structure is installed as a lower air valve in the middle of the casing, the driving cylinder needs to be installed protruding outside the casing at almost the same height as the air valve. The protruding portion of the casing becomes an obstacle to penetrating the casing into the ground, which is undesirable.

The present invention aims to solve the problems of the conventional sand pile building apparatus described above.

(Technical Means for Solving the Problems) The sand pile construction device of the present invention that can achieve the above-mentioned object has an upper and an intermediate portion in a casing that is suspended from a lower part of a machine frame suspended by a leader. An upper air valve and a lower air valve are provided in the upper and lower air valves, respectively, which are opened and closed by valve opening/closing drive means, and a sand stock space is formed between the upper and lower air valves and below the lower air valve. Each air valve was a sand pile building device equipped with compressed air supply means for supplying compressed air to each of the sand pressing spaces.
The valve frame is installed concentrically within the casing, and the inner rod is concentrically suspended from the bottom of the machine frame into the casing. A valve body that can be abutted and engaged from below, and a fluid pressure cylinder installed outside the casing for the valve opening/closing driving means, and a sheave that penetrates the casing and connects to the piston rod of the fluid pressure cylinder and the valve body. It is characterized by being composed of wires that are connected through the wire.

(Example) Next, an example of the present invention will be described based on the drawings.

Figure 1 shows a sand pile construction device for carrying out the method of the present invention, and in this figure, 1 is a machine frame that is lifted and lowered and suspended from a leader (not shown) installed upright, such as a crawler crane. A cylindrical casing 2 is suspended from the lower part of the machine frame 1, and a sand supply hopper 3 is provided at the upper end of the casing 2. Reference numeral 4 denotes an exciter as a drive means for driving the casing, which is installed within the machine frame 1 and is integrally connected to the upper end of the casing 2. 5 is an upper air valve provided in the upper part of the casing 2 and below the hopper 3; 6 is a lower air valve provided in a required position in the middle of the casing 2; these upper and lower air valves 5 and 6 are They are opened and closed as appropriate by opening/closing driving means 7 and 8, respectively. Also, within this casing 2, a space 9 for sand stock is provided between the upper air valve 5 and the lower air valve 6.
At the same time, a sand pressing space 10 is formed from the lower air valve 6 to the lower end of the casing 2, and a compressing space 10 is formed at the upper end of the sand stock space 9 and the sand pressing space 10. Compression nozzles 11 and 12 are provided as air supply means, respectively.

The upper air valve 5 includes a substantially funnel-shaped valve frame 5c provided on the inner peripheral surface of the casing 2 concentrically with the casing, a valve seat 5b formed at the lower end opening of the valve frame 5c, and a substantially disc-shaped valve frame 5c. The valve body 5a is vertically slidably inserted and supported by an inner rod 13 which is suspended from the lower part of the machine frame 1 into the casing 2 along the central axis of the casing. The lower air valve 6 has exactly the same structure and is composed of a valve frame 6c, a valve seat 6b, and a valve body 6a, and the valve body 6a is inserted into and supported by the inner rod 13 so as to be vertically slidable. The valve bodies 5a, 6a are moved up and down by valve opening/closing driving means 7, 8 to perform opening/closing operations, respectively, and these valve opening/closing driving means 7, 8 are operated by hydraulic cylinders 7a, 8a and a plurality of sheaves, respectively. 7
b..., 8b... and the cylinders 7a, 8
It consists of wires 7c and 8c that connect the piston rod of a and the valve bodies 5a and 6a, and the valve bodies 5a and 6a are moved along the inner rod 13 via the wires 7c and 8c as the piston rods of the cylinders 7a and 8a expand and contract. It is designed to open and close the valve by sliding up and down. The valve bodies 5a and 6a are the casing 2
The upper surface of the valve body 5a, 6a is formed in a mountain-shaped or conical shape so that the sand thrown into the valve body 5a, 6a contacts the valve seats 5b, 6b. Seal materials 5d and 6d made of rubber or the like are attached to the parts. The wires 7c and 8c extend in and out of the casing 2 through wire insertion holes (not shown) provided through the casing 2, and there are gaps between the wires 7c and 8c inserted into the wire insertion holes. A member is attached to seal the wire and facilitate sliding of the wire.

Further, an open/close type shoe 14 is attached to the lower end of the casing 2, and this shoe 14 closes when the casing 2 is driven into the ground, and opens when the casing 2 is pulled out from the ground.

The sand pile construction method using the sand pile construction device having the above-mentioned configuration will be explained with reference to Fig. 2 A to H. First, this device is installed, for example, from the top of a leader (not shown) installed on a crawler crane. From the suspended and supported state at an appropriate height (Fig. 2 A), unwind the winch on the crane side and unwind the casing 2.
While lowering the casing 2, the exciter 4 is activated to drive the casing 2 into the ground. When the casing 2 reaches a predetermined depth in the ground as shown in FIG. Pour in up to a certain amount. Note that the air valves 5 and 6 may both be opened in advance before the casing 2 is driven in, or may be opened at the time of the first sand injection as described above. After the first certain amount of sand has been introduced, the casing is pulled out by winding the drum.
As shown in FIG. Sand is then poured into the sand stock space 9 for the second time. The same applies to the case of the first sand injection mentioned above, but there is a gap between the sand tank (not shown) installed at the lower part of the leader and the hopper 3 at the upper end of the casing. This is done by reciprocating a sand charging bucket (not shown) along the leader several times, so that by the time the sand loading work into the sand stock space 9 is finished, the sand pressing space 10 is compressed. There is sufficient air supply. The compressed air presses the sand in the space 10 while pulling out the casing 2, pushing out the sand from the lower end of the casing 2, and as shown in Fig. 2D, the sand pile portion _P1 is consolidated into the ground. will continue to form.
Next, the supply of compressed air from the nozzle 12 is stopped, the lower air valve 6 is opened, and the upper air valve 5 is closed, and compressed air is supplied downward from the upper nozzle 11 into the stock space 9. A certain amount of stored sand is rapidly dropped into the lower part of the pressing space 10 through the opened lower air valve 6 (see FIG. 2, E). Once a certain amount of sand has been poured into the space 10, the lower air valve 6 is closed again and the upper air valve 5 is opened, as shown in FIG. Stop the supply and open the lower nozzle 1.
The supply of compressed air from 2 to the sand pressing space 10 is started, and at the same time as the supply of compressed air to this space 10, sand is being poured into the sand stocking space 9, and the sand is While pressing the sand in the pressing space 10 with the compressed air, the sand is pushed out from the lower end of the casing 2 while pulling out the casing 2.
As shown in Figure E, a sand pile portion P ₂ is formed continuously above the sand pile portion P ₁ that has already been formed.
Thereafter, the steps shown in Figure 2 C to H are repeated several times to create a sand pile of a predetermined length.

Fig. 3 shows another embodiment of the sand pile making device, which is slightly different from the device shown in Fig. 1. Support stand 1 on four pillars 15...
A vibration exciter 17 is fixedly mounted on the support base 16 so as to be able to move up and down. The upper ends of the inner rods 18 are connected and fixed, and air springs 20, 20 (hydraulic or air cylinders, etc. may be used) are installed between the support stand 16 and the base 19 of the machine frame 1' as means for vertically driving the inner rods. is interposed, and this air spring 2
The inner rod 18 is moved up and down by vertical expansion and contraction movements of 0 and 20, and a connecting piece 21 is provided on the inner rod 18 to appropriately transmit the vibration of the exciter 17 to the casing 2. is air spring 2
0 and 20 are fully extended, abutment pieces 22 are integrally provided at required locations on the casing 2.
Due to this contact, the vibration of the exciter 17 is transmitted from the connecting piece 21 to the contact piece 22.
It will be transmitted to the casing 2 via. When moving the inner rod 18 up and down, air springs 20, 2
The upper limit position of the 0 stroke is limited to a position slightly before (below) the maximum extension position for expansion and contraction, so that no vibration is transmitted to the casing 2 when the inner rod 18 moves up and down. Further, the valve bodies 5a and 6a of the upper and lower air valves 5 and 6 are connected to the inner rod 1.
It is attached so that it can slide with respect to 8.

Although only the different parts have been described above, the other constituent parts are almost the same as the apparatus shown in FIG. 1, so the explanation thereof is omitted, and the same members are given the same reference numerals. Regarding the operation of the device shown in Fig. 3, the casing 2
When driving, the air springs 20, 20 are held in a fully extended state to fix the inner rod 18 in the raised position, and the connecting piece 21 is brought into contact with the contact piece 22, so that the vibration of the exciter 17 is transmitted to the casing 2. west,
Then, when pulling out the casing, the connecting piece 21 and the backing piece 22 are unconnected, and the inner rod 18 is moved up and down with a predetermined stroke by the air springs 20, 20, and the tip of the inner rod 18 presses sand on the casing 2. This device differs from the device shown in FIG. 1 in that the sand in the space 10 is compacted, and other operations are completely the same. According to the apparatus of the embodiment shown in FIG. 3, when the casing 2 is pulled out, the compressed air supplied from the nozzle 12 in the sand pressing space 10 presses the sand in the space 10, and the inner rod 18 mentioned above is pressed. Since the sand is tamped by the sand, it is possible to form extremely strong sand piles.

(Effects of the Invention) The present invention does not use the entire space inside the casing as the space for sand pressing as in the past, but uses the space below the lower air valve provided in the middle part of the casing as the space for sand pressing. , the amount of compressed air supplied each time can be reduced, and compressed air can be supplied in a short time.

In addition, in the present invention, each air valve is inserted and supported so as to be vertically slidable through a valve frame provided concentrically within the casing and an inner rod extending concentrically from the bottom of the machine frame into the casing. a valve body capable of abutting and engaging the valve seat at the lower end of the valve frame from below;
In addition, since the valve opening/closing driving means is composed of a fluid pressure cylinder installed outside the casing, and a wire that passes through the casing and is connected to the piston rod of the fluid pressure cylinder and the valve body via a sheave, Sand grains and dust do not adhere to the piston rod of the fluid pressure cylinder, so sand grains, etc. do not enter the cylinder or damage the piston rod sliding part, and the service life of the fluid pressure cylinder can be extended. Also, even if the lower air valve is installed in the middle of the casing, the fluid pressure cylinder that drives it can be installed on the upper side of the casing by extending the wire appropriately, so it can be installed into the ground of the casing. There is no inconvenience caused by the hydraulic cylinder becoming an obstacle during penetration. Furthermore, since the valve body of each air valve is vertically slidably guided by the inner rod, the air valve can be opened and closed reliably.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a sand pile making device showing one embodiment of the present invention, FIGS. The figure is a longitudinal sectional view showing another embodiment of the sand pile construction device. DESCRIPTION OF SYMBOLS 1...Machine frame, 2...Casing, 3...Sand supply hopper, 4...Exciter (drive means for driving casing), 5...Upper air valve, 6...Lower air valve, 5a,
6a... Valve body, 5b, 6b... Valve seat, 5c, 6c...
Valve frame, 7, 8... Valve opening/closing drive means, 7a, 8a... Hydraulic cylinder (fluid pressure cylinder), 7b, 8b... Sheave, 7c, 8c... Wire, 9... Space for sand stock, 10... Space for sand pressing. Parts, 11, 12... Compressed air supply nozzle (compressed air supply means).

Claims (1)

[Claims] 1. An upper air valve and a lower air valve that are opened and closed by valve opening/closing drive means are provided in the upper and intermediate parts of a casing that is connected to the lower part of the machine frame suspended by the leader, respectively. In addition, a compressed air supply means is provided for supplying compressed air to the sand stock space formed between the upper and lower air valves and the sand pressing space formed below the lower air valve. It is a sand pile making device, and each air valve is
The valve frame is installed concentrically within the casing, and the inner rod is concentrically suspended from the bottom of the machine frame into the casing. A valve body that can be abutted and engaged from below, and a fluid pressure cylinder installed outside the casing for the valve opening/closing driving means, and a sheave that penetrates the casing and connects to the piston rod of the fluid pressure cylinder and the valve body. A sand pile construction device characterized by comprising: wires connected via a wire; 2. The sand pile making device according to claim 1, wherein the inner rod is made vertically movable by a vertical drive means provided on the machine frame.