JPS61290117A - Holding of excavated pit for rubble layer - Google Patents

Abstract

PURPOSE:To hold excavated pit for rubble layer with good efficiency by a method in which a pit is excavated in a rubble layer by an auger screw, and slurried sand is packed into the pit through the hollow shaft of the screw while pulling out the screw. CONSTITUTION:A hollow casing 1 is turned to the direction of arrow A, and an auger screw 2 is turned to the direction of arrow B to excavate a pit 5 in a rubble layer 4 on the bottom 3 under water. While pulling out the screw 2, slurried sand 7 is packed through the hollow shaft 2A into the pit 5. After the casing 1 is drawn out, a pile is driven into the sand 7 in the pit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for driving piles into a rubble layer, in which a hole is dug in the rubble layer and the back portion of the hole filled with sand is driven into the hole.

[Prior art]

The chestnut stones that form the rubble foundation on the underwater ground are 20 mm in diameter.
Since the size of the pile is from an to ioocm, in order to penetrate the rubble foundation, first use a rock auger to drill a hole in the rubble foundation with a diameter larger than the diameter of the pile, and then drill a hole into the rubble foundation. One possible method is to drive piles.

However, in this case, when the auger screw of the rock auger excavator is pulled out while being reversed, the auger head at the tip of the auger screw breaks the stone pressed against the hole wall during excavation and collapses into the hole. However, there is a problem in that the drilled hole becomes clogged, making it impossible to drive the next pile.

As a countermeasure to this problem, the hole is filled with sand as described above to prevent the wall from collapsing and facilitate the subsequent driving of piles.
An invention related to a method for driving piles into a rubble layer is known.

Other conventional methods using a Dona Sotu auger are also known.

The method using the Dona Sooga excavator is shown in Figures 6 to 1.
To explain with reference to a series of drawings up to Figure 0, first, in Figure 6, the steel hollow casing 1 mounted on the Donazoga excavator is rotated in the direction of arrow A by an outer excavator (not shown). Meanwhile, the auger screw 2 penetrated inside is rotated by an inner excavator (not shown) in the direction of arrow B, that is, in the opposite direction to arrow A, to remove the rubble layer 4 formed on the underwater bed ground 3. dig inside.

In this case, the auger screw 2 is placed in front and the hollow casing 1 follows, and the hole 5 is excavated to the predetermined depth shown in Fig. 7 while pushing the rubble outward during excavation to complete the drilling. do.

Next, as shown in Fig. 8 (after pulling out only the auger screw 2 while rotating, a belt conveyor 6 etc. is used in the hollow casing 1 left in the drilled hole 5 as shown in Fig. 9). and fill it with sand 7 for filling.

Thereafter, the hollow casing 1 is inserted into the hole 5 as shown in FIG.
The piles are easily driven by pulling them out from the hole 5 and driving the piles (not shown) into the pillars of sand 7 filled in the holes 5.

However, in the above conventional method of driving piles into the rubble layer 4, sand 7 is filled using a belt conveyor 6 etc. after the auger screw 2 is pulled out, so when driving piles in a place close to a quay, However, the belt conveyor 6 may not be able to be used at a location far from the quay, and the work efficiency is also poor.

In addition, in the case of diagonal piles, the auger screw 2 cannot be removed from the hollow casing 1, so there is a drawback that the efficiency of sand injection is extremely low.

[Purpose of the invention]

Therefore, in order to solve the above-mentioned conventional problems, the present invention utilizes the hollow shaft of the auger screw when filling sand into the hole excavated by the auger screw of the donut auger excavator. By introducing sand into the hole to form a sand column, it is possible to efficiently hold the ripble layer in the hole without using a conveyor for sand supply, and also to prevent the ripple layer from being removed underwater away from the quay. The purpose is to enable drilling and retention.

[Structure of the invention]

That is, in the method of driving piles into a rubble layer according to the present invention, after drilling a hole in the rubble layer with an auger screw, the pile is pulled out through the hollow shaft of the auger screw formed in the hollow. This method is characterized in that the slurry-like sand supplied is filled into the hole excavated as described above.

〔Example〕

An embodiment of a pile driving operation using the drilling holding method of the present invention will be described below with reference to the drawings, and FIG. 1 is a schematic side view of a donut two auger excavator for drilling drilling in one embodiment. It is.

This donut auger excavator is for excavating a hole 5 in the rubble layer 4 on the water bottom ground 3 below the water surface W, as in the conventional example. Excavation is carried out by rotating the hollow casing 1 in the direction of arrow A and rotating the auger screw 2 in the direction of arrow B using the inner excavator 10.

Next, a sand feeding pipe 12 is connected to the upper end of the hollow shaft 2A formed in the hollow of the auger screw 2 via a swivel joint 11.

On the other hand, a stirring tank 14 is provided on the sand supply ship 13, and while the sand 7 is supplied into the stirring tank 14 by a conveyor 18, water is supplied by a submersible pump 15, and the mixture is stirred to form a slurry. The sand 7 is transferred to the hollow shaft 2A of the auger screw 2 via the sand pipe 12 using the sand pump 16.
It is possible to discharge from the lower end.

Next, the work of maintaining the drilling of the rubble layer 4 using the donut tsuuger excavator with the above configuration will be explained according to FIGS. 2 to 5. FIG. 2 is similar to the conventional example shown in FIG. 6. The auger screw 2 and the hollow casing 1 are rotated to perform drilling work, and FIG. 3 shows a completed drilling operation similar to the conventional example shown in FIG. 7.

Therefore, as shown in FIG. 4, when pulling out only the Augusta screw 2, slurry-like sand 7 is drilled into the hole 5 from the lower end of the hollow shaft 2A of the Augusta screw 2.
The hollow casing 1 in the hole 5 is filled with the sand 7 as shown in FIG. 5.

At this time, the speed at which the auger screw 2 is pulled out from the hollow casing 1 can be constantly controlled by controlling the amount of sand fed.

Thereafter, the hollow casing 1 is pulled out and piles are driven into the remaining pillars of sand 7, as in the conventional example shown in FIG. 10.

In addition, in the method for driving piles into the rubble layer 4 of the present invention, the lower end portion of the hollow shaft 2A of the auger screw 2 is closed during excavation, and when pulled out.

The structure is such that the lower end thereof is open and slurry-like sand 7 can be discharged.

〔Effect of the invention〕

Therefore, if the method of driving piles into the rubble layer of the present invention is adopted, it is possible to easily drive piles into the rubble layer at a location away from the quay. Compared to the conventional method, in which sand is filled after the auger screw is completely pulled out, the work time can be shortened, and filling sand can be efficiently injected into the hole. There is an effect.

The present invention can be particularly effectively applied to pile driving work when there are obstacles in the rubble layer or soil, but it can also be applied to various types of pile driving work in civil engineering works.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of a rock auger excavator for driving piles in an embodiment of pile driving work using the pile driving method of the present invention, and FIGS. 2, 3, 4, and 5 are Figure 1 is a series of schematic side views illustrating hole excavation work using a rock auger excavator, and Figures 6, 7, 8, 9, and 10 are a series of schematic side views illustrating hole excavation work using a rock auger excavator, and Figures 6, 7, 8, 9, and 10 are a series of schematic side views illustrating hole excavation work using a rock auger excavator. FIG. 3 is a series of schematic side views illustrating a hole drilling operation using a pile driving method. 1...Hollow casing, 2...Auger screw,
2A... hollow shaft, 4... rubble layer, 5... hole, 7... sand, 12... sand feeding pipe, 14... stirring tank, 16... sand pump.

Claims (1)

[Claims] After drilling a hole in the rubble layer with an auger screw, the hole is filled with sand in the form of slurry, which is supplied via the hollow shaft of the auger screw while pulling out the auger screw. Characteristic drilling retention method for rubble layer.