JPH02108716A - Levee dam and bulkhead for ill-conditioned soil - Google Patents

Abstract

PURPOSE:To obtain a water-tight bank unnecessary for inside reclamation in permeable soil by driving sheet piles in the front and the rear bottom portions of the water-tight bank, injecting water-tight coagulant in between the pile and the water-tight bank and in an overall foundation and permitting drainage by means of a pump. CONSTITUTION:Sheet piles 7, 10 the joints of which are given water tightness are continuously driven in parallel with the front and the rear bottom portions of a water-tight bank 1. Then, in both sides of the seat pile 7 and in an overall foundation water-tight coagulant 16 is injected to stabilize soil. Also steel pipes 6, 6... are driven in a foundation surface 4. Additionally, at the rear portion of the water-tight bank 1 a horizontal catchment pipe 17 and a column pipe 12 are arranged to perform drainage by means of a storage pump 13 into a drainage ditch 14. That results in easy installation in permeable, weak and ill-conditioned soil and effective use of a rear ground surface 15 without necessity of internal reclamation.

Description

[Detailed description of the invention] (Purpose of the invention) To create new acid formations in soft and poor permeability geology (lakes, rivers, oceans, etc.), by combining embankments and dam structures without reclaiming the inside. It is a rational method, and underground seepage water is drained rationally.

Even in areas with poor geology in mountainous and hilly areas, it is a rational construction method such as water storage dams, river and underwater embankments, and artificial islands along the waterfront. ＼ (Structure of the invention) When installing structures such as embankments and dams in incompatible geological formations, the joints of sheet piles, etc. (steel plates, etc.) of impermeable walls are installed in parallel and close to the embankment body before and after the embankment dam. After waterproofing, insert continuous pouring and gradually graft waterproofing material under pressure into the gap between the impermeable wall and embankment dam, and stabilize the front surface by grafting waterproofing material on the front of the front impermeable wall. In addition, water collection pipes (upper perforation structure) are buried horizontally at a certain depth in front of the rear impermeable wall (at the rear of the embankment dam) to collect water at various locations and pump it up and discharge it. In cases where there is a large amount of water, the impermeable wall and water collection pipe should be installed in multiple stages, which is a rational method for pumping water.

(Effect of the invention), ``
It can be installed in soft and poorly permeable geology," and as a result, "
Not only is it possible to install dams in lakes, rivers, oceans, etc., but also embankment dams on artificial islands, and in the case of artificial islands, there is no need for internal reclamation, and the blank space (at the same level as the water bottom) can be used effectively in a rational manner. , a new Otterfront structural construction method, can be easily installed anywhere, especially in permeable geology, by using an impermeable wall and water collection construction method.

In particular, for gravity dams and rockfill dams other than arch dams, ``the dam installation area is significantly reduced, conversely, water storage capacity is increased, construction materials such as rocks are greatly saved, construction period and costs are significantly shortened, and water pressure and seepage water are significantly reduced. However, it is very safe.'' (Most of the causes of dam and levee failures are leakage caused by seepage water.)

Figure 1: Embankment dam on permeable geology, cross-sectional view, a waterproof embankment is installed at the bottom of the water in permeable geology 3, an impermeable wall of 7 sheet piles in front of the embankment, and an 8 graph in the gaps 1 and 7. Waterproofing material is injected through a water pipe to ensure geological stability (3) and waterproofing, and (4) the bottom of the waterproof embankment is serrated to prevent slips due to water pressure.

The seepage water is collected horizontally between the 10 rear sheet pile and the ice wall 11 with the 17 water collection pipe (upper hole), pumped up with 12 and 13, and then drained into the 14 drainage ditch. is at the same level.

Inside the temporary sleeve pipe 5, drive a steel pile 6 to the underground support ground to ensure safety.Insert the grafting pipe along with 6 inside the pipe 5, and inject waterproof coagulation material over the entire foundation for stability.After that, The gaps 5 and 6 are filled with a bonding material and fixed.

[Brief explanation of the drawing]

Figure 1: A cross-sectional view of an embankment dam on permeable geology. Sheet piles for impermeable walls are inserted before and after the embankment dam, waterproofing material is poured over the entire surface using graphing, and water collection pipes are installed at the rear for pumping and drainage. Cross-sectional view. (Symbol), 1-Waterproof embankment, 2-Water surface, 3-Water bottom, 4-Waterproof embankment bottom, 5
- Sleeve pipe, 6 - Steel pile, 7 - Front sheet pile, 8 - Gap grafting pipe, 9 - Front grafting pipe, 10 - Rear sheet pile, 11 - Water stop wall, 12 Lifting pipe, 13 - Pump, 14-Drainage ditch 15
- rear ground surface, 16 - waterproof material, 17 - horizontal water collection pipe.

Claims (1)

[Claims] In geology with poor permeability (lakes, marshes, rivers, oceans, etc.), water storage dams are installed in mountainous and hilly areas, and levees are installed for seawater and freshwater, etc., without reclamation on one side, and with impermeable walls and concentrated pumping. This is a construction method that makes efficient use of the space on the same level as the bottom of the water. The joints of sheet piles, etc. of the impermeable wall are waterproofed and continuously inserted in parallel to the front and back of the dam dam and the embankment (hereinafter referred to as the embankment dam) to create a bridge between the impermeable wall and the embankment dam. Waterproofing material was grafted deeply into the gap using pressure, and the same graphing was applied to the front of the front impermeable wall to ensure stability, and a water collection pipe (upper A method is to bury water (Komei) horizontally and use water pumps to concentrate the water in various locations, and if there is a large amount of seepage water, it can be pumped up and drained by installing impermeable walls and water collection pipes in multiple stages.