JPS63284398A - Packing device for gable frame in shield excavator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a packing device for a gable in a shield excavator, particularly a shield excavator for directly pouring concrete lining.

(Prior art) As shown in FIG. 3, a shield excavator for directly pouring concrete lining is provided with an annular gable 2 on the inner circumferential surface of the tail portion of a shield body 1. A plurality of end frame jacks 4 are used to slide between the frame 3 and the outer circumferential surface of a formwork 3 disposed inside the frame. 5
Reference numeral 6 indicates an inner seal member that closes the space between the inner periphery of the end frame 2 and the formwork 3, and 6 indicates an outer seal member that closes the space between the outer periphery of the end frame 2 and the tail portion.

During construction, as the shield body 1 is propelled by a propulsion jack (not shown) (in the direction of the arrow in Fig. 3), concrete is poured between the tail part and the formwork 3 from the supply port provided in the end frame 2. The concrete 9 is pressed by the end frame 2 and brought into close contact with the ground 10.

(Problems to be Solved by the Invention) By the way, both the inner and outer seal members 5 and 6 are for preventing leakage of concrete 9, and the outer seal member 6
is made of hard rubber or the like, and is pressed toward the inner circumferential surface of the tail portion by mechanical means in order to resist the concrete placing pressure. However, for the inner seal member 5, since the clearance between the end frame 2 and the formwork 3 constantly fluctuates (particularly large during curve construction), measures such as those adopted for the outer seal member 6 should not be taken. For this reason, a strong material such as a stainless steel plate is used as the inner sealing member 5 to prevent concrete from leaking, but it is not watertight and water leakage is likely to occur under high groundwater pressure. There was a problem.

The present invention was made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a packing device that can reliably prevent water leakage between the end frame and the formwork.

(Means and effects for solving the problem) In order to achieve the above object, the present invention has an inner sealing member between the end frame and the formwork, which is arranged twice at the front and rear in the axial direction of the shield body, The front seal member is water-impermeable and the rear seal member is concrete-impermeable, so that even if water leaks from the rear seal member, water will not enter the shield body from the front part. This is prevented by the seal member.

(Embodiment) FIGS. 1 and 2 respectively show two different embodiments of the present invention, and the same reference numerals are given to the same members as those in the prior art.

In the embodiment shown in FIG. 1, inner seal members 7 and 8 between the end frame 2 and the formwork 3 are arranged doubly at the front and rear of the shield body 1 in the axial direction.

The front seal member 7 is made of a flexible tube and is connected to the supply pipe 1.
It expands by supplying air from 1, and water impermeability between the end frame 2 and form 3 is maintained.

The rear seal member 8 is made of a stainless steel plate, a hard rubber plate, etc., as in the past, and has strength to withstand the concrete placing pressure and maintains its impermeability.

In the embodiment shown in FIG. 2, the front seal member is constituted by a wire brush 12 and a viscous filler 13 such as grease filled behind the wire brush 12 through a supply pipe 14, and the rest is the same as in the previous embodiment. be. In this case, the wire brush 12 and the filler 13 work together to maintain water impermeability between the end frame 2 and the formwork 3.

The above embodiments are merely illustrative, and the present invention can be modified in various ways.

(Effects of the Invention) As described above, according to the present invention, a rear seal member for preventing leakage of concrete is arranged between the end frame and the formwork, and a front seal member for preventing water leakage is arranged in front of the rear seal member for preventing leakage of water. With this arrangement, water leakage can be reliably prevented even under high groundwater pressure, and construction can be carried out safely.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention, FIG. 2 is a sectional view showing another embodiment, and FIG. 3 is a sectional view showing a conventional example.

Claims (1)

[Claims] 1. It has an annular end frame that is slidable between the inner circumferential surface of the tail portion of the shield body and the outer circumferential surface of a cylindrical formwork placed inside the tail portion, and In a shield excavator in which a sealing member is provided on the inner periphery to close the space between the sealing member and the outer peripheral surface of the formwork, the sealing member is arranged twice at the front and back in the axial direction of the shield body, and the front sealing member is water-impermeable. 1. A packing device for a gable in a shield excavator, characterized in that the rear seal member is impermeable to concrete.