JPH0312637B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a trailed shield excavation method.

In the shield excavation method, an excavation device is installed inside the shield machine body, a tubing is installed behind the shield machine body, a hydraulic piston cylinder device is placed in the tubing via one pile pressure ring, and this piston cylinder It is well known that a shield machine is pushed and propelled by the operation of a device. In addition, multiple shield jacks are placed around the front of the shield machine body to control the direction of the blade, and corrections can be made if the shield machine cuts a curve or deviates from the intended route due to the pressing action of these shield jacks. It is also well known that However, with this type of shield propulsion method using pressure propulsion or direction control, if some hard rocks, coarse gravel, buried trees, or existing structures appear in the soft ground, the propulsion direction of the shield machine may be upward or downward. Otherwise, the excavation along the intended route could become impossible due to deviations in irregular directions. Additionally, if even softer ground appeared within the soft ground, the shield machine would sink significantly, making it impossible to excavate along the intended route.

By the way, in order to solve the problems of the above-mentioned push-type shield excavation method, the towed excavation method was developed in 1987-8226.
It is proposed in the Publication No. When excavating a horizontal hole below the embankment body, the movable part of the center hole jack is extended and the element is excavated via the traction member, and the jack reaction force is applied to the ground reaction force retaining wall in front of the cylinder body. It is supported by the ground reaction force of the soil, and then the anchoring device is operated to release the anchorage between the traction member and the movable part of the center hole jack, and the movable part is retracted to its previous position, and then the movable part is reattached to the movable part. Anchor the traction member and extend it, repeat the same operation, and when the element has progressed, attach the support plate and anchoring member arranged at the end of the next element to the long bolt. By repeating the same operations as above, a horizontal hole whose inner circumferential wall is covered with an element is dug into the ground. However, this type of towing excavation method requires work to penetrate the towing member into the lower part of the embankment body in advance, so the length of the horizontal hole to be excavated is extremely limited, making it difficult to excavate long horizontal holes. In addition to being indispensable, the traction member that is penetrated in advance tends to have a large error in the traveling direction, so there is a problem in that the horizontal hole that is towed and excavated via the traction member also tends to deviate from the intended route.

In view of the above circumstances, the present invention aims to provide a towed excavation method that enables excavation of long horizontal holes and excavation accurately along the target route.
The feature is that the main body of the shield machine is equipped with a guide bar equipped with an excavation head and fixing means for the excavation head, and a traction and propulsion mechanism connected to this guide bar. After digging forward from the cutting edge and fixing the excavation head of the guide bar in the ground by the fixing means, the shield machine main body is pulled by using the fixed guide bar as a towing guide by the operation of the traction and propulsion mechanism. After that, the anchorage is released, the guide bar is dug forward from the cutting edge, the excavation head is anchored, and the shield machine body is towed and propelled, and the guide bar is dug and anchored and the shield machine body is towed and propelled. According to the shield excavation method of the present invention, the guide bar is set to a desired length, for example, 3.
After excavating approximately 5m, the excavation head is fixed in the ground, and the shield machine is towed and propelled using the fixed guide bar as a towing guide. This eliminates the work of penetrating the towing member in advance, which is required in the past. This makes it possible to tow the hole, and in addition, it enables excavation along the target route for towing and propulsion by repeating the digging and fixing of the guide bar for the desired length, which is necessary when towing and propulsion of the shield machine body. Depending on the situation, a pressing jack is also used.

Next, the embodiment will be described with reference to the attached drawings. The shield machine body 1 is arranged at the axis position via the universal joint 2, and is connected to the excavation head 3 and a fixing means (not shown) of the excavation head 3, for example, from a location near the excavation head. A guide bar 4 with a diameter of 50 to 100 mm, for example, is connected to the main body of the shielding machine, and is equipped with a device for pouring out grout or a device that enables the opening and closing of the excavation head of a excavation drill, etc., and fixes it by opening it, and releases it by closing it. The shield machine main body 1 is equipped with a traction device 6 that winds up a traction member 5 connected to the tip of a guide bar 4, for example, and a traction device 6 that winds up a traction member 5 connected to the tip of a guide bar 4.As shown in FIG. 4 is positioned, first, as shown in FIG.
As shown in the figure, grout is guided into the guide bar 4 by a grout pouring device (not shown), and the grout 8 is poured into the ground 9 from the grout spout at the tip of the guide bar 4, and the excavation head 3 is fixed in the ground 9. do. Thereafter, the traction device 6 fixed on the shield machine main body 1 is activated, and the traction member 5 connected to the tip of the guide bar 4
By winding up the shield machine body 1, the shield machine main body 1 is towed and propelled while being excavated by an excavator (not shown) using the fixed guide bar 4 as a towing guide as shown in FIG. Thereafter, as shown in Fig. 5, the grout 8 is destroyed by rotating the guide bar 4 to release the fixation, and the guide bar 4 is dug to a desired length from the cutting edge as shown in Fig. 2, and as shown in Fig. 3. The drilling head 3 is fixed by pouring out the grout 8, and then the traction device 6
The shield machine main body 1 is towed and propelled by the operation of
In this way, the shield excavation is carried out while repeating the steps of propelling and fixing the guide bar 4 and towing and propelling the shield machine body 1. In this case, although a case has been shown in which the traction and propulsion mechanism consists of a winder and a traction member, a guide bar may be used as the traction member and the guide bar may be intermittently pulled by a jack. FIG. 6 shows a case where the direction of the guide bar 3 is changed via the universal joint 2 by a direction control mechanism (not shown) such as a jack.

By repeating the digging and fixing process of the guide bar 4 and the process of towing and propelling the shield machine main body 1, it becomes possible to accurately tow and propel the shield machine main body 1 several meters at a time.
Even when coarse gravel appears, it is possible to excavate straight or curved with high accuracy. Further, since the direction of the guide bar 3 can be changed freely via the universal joint 2, the direction of excavation can be corrected accurately and easily. Furthermore, since the shield machine can be propelled using the guide bar 3 as a guide, the extension of propulsion is longer than that of a semi-shield using a pressure jack, and the primary lining can be cast on site. In addition, during propulsion and direction correction, the load applied to the propulsion tube and shield is smaller compared to the push type, so the breakage rate is low. It goes without saying that a pressing jack may be used in conjunction with the construction method of the present invention to propel the shield machine.

As described above, the present invention includes a shield machine body equipped with a guide bar having an excavation head and a fixing means for the excavation head, and a traction and propulsion mechanism connected to this guide bar, After digging forward from the cutting edge of the shield machine main body and fixing the excavation head of the guide bar in the ground by the fixing means, the shield machine main body uses the fixed guide bar as a traction guide by the operation of the traction and propulsion mechanism. After that, the fixation is released, the guide bar is dug forward from the cutting edge, and the excavation head is fixed, and the shield machine body is towed and propelled, and the guide bar is dug and fixed and the shield machine body is fixed. Since the traction and propulsion process is repeated, it is possible to excavate long horizontal holes, accurately excavate, and easily correct the direction, which has excellent effects.

[Brief explanation of the drawing]

1 to 5 are cross-sectional views showing the excavation method of the present invention, FIG. 6 is a cross-sectional view showing a direction correction state, and FIG. 7 is a cross-sectional view taken along the line A--A in FIG. 1. 1... Shield machine body, 3... Excavation head, 4
... Guide bar, 5 ... Traction member (traction and propulsion mechanism),
6... Traction device (traction and propulsion mechanism).

Claims (1)

[Claims] 1 The shield machine body is equipped with a guide bar having an excavation head and a fixing means for the excavation head, and a traction and propulsion mechanism connected to this guide bar, and the guide bar is connected to the blade of the shield machine body. After digging forward from the mouth and fixing the excavation head of the guide bar in the ground by the fixing means, the shield machine main body is towed and propelled using the fixed guide bar as a traction guide by the operation of the traction and propulsion mechanism, Thereafter, the anchorage is released, the guide bar is dug forward from the cutting edge, the excavation head is anchored, and the shield machine body is towed and propelled, and the digging and anchoring of the guide bar and the traction and propulsion of the shield machine body are repeated. A towed shield excavation method characterized by: