JPH02279810A - Method of repairing revetment in coast, harbor and the like - Google Patents

Abstract

PURPOSE:To improve work efficiency to reduce a construction period and to make it possible to execute repairing work of a revetment with safety and certainty by pouring chemicals into a hole bored the hollow of the rear side of the revetment from the ground surface to cover a gap with a waterproof seal, and executing backfilling. CONSTITUTION:An injection pipe 9 is erected into a hole bored to the hollow 5 of the rear side of revetment blocks 2 from the ground surface, and the end thereof is set to the level of a gap 6. After that, water absorbing porima is poured by means of an injection pump 10 to form a cut-off film into the gap 6. Then, isocyanate compound is injected to form a solidified film, and cement milk is also injected to form a cut-off seal with high strength. After the completion of the seal, the backfilling of mortar and the backfilling of earth, etc. are carried out. According to the constitution, the execution is possible is dependent of whether there exists the seawater or not, and water stop agent is injected from the ground surface, so that work efficiency is improved, and a construction period can be reduced to repair with safety and certainty.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for repairing seawalls on coasts, ports, etc.

[Conventional technology]

On coasts, ports, etc., backfilled soil from the coast and ports is washed away due to the effects of tides and waves caused by wind, causing the collapse of seawalls and ground subsidence.

That is, as shown in Fig. 3, the revetment blocks 2, etc. placed on the paving stones 1 are able to penetrate through the joints 3 and the gaps in the paving stones 1, which can be a perfect water-blocking wall. Seawater 4 invades. This intruding seawater 4 is sucked out by the effects of tides and waves caused by wind, and constantly moves back and forth. The movement of this seawater 4 brings out the earth and sand on the back side of the seawall block 2, forming a cavity 5. As a result, the revetment block 2, which lost its backup, collapsed and caused ground subsidence.

Conventionally, as a means of backfilling the cavity 5, earth and sand was originally thrown in from the ground surface to backfill, or mortar was poured in to backfill. However, since this backfilling work was carried out in a place where heavy machinery could not be brought in, earth and sand were simply thrown in from the ground. As a result, tamping and compaction are not performed sufficiently, and there are constant waves even during backfilling, so the earth, sand, mortar, etc. that have been put in are sucked out before they are fixed.

Therefore, we put in rapid hardening cement, and as shown in Figure 4, we installed the revetment block 2, which is the outflow route for the backfilled soil.
After sealing the gap 6 at the joint 3 and the crack (not shown) from the outside with quick-hardening cement, cloth, wood chips 7, etc., pour earth and sand, mortar, etc. It is being backfilled.

Alternatively, as shown in the figure, polling 8 is performed on the gap 6. Gap 6 via a press-fit pump or injection pipe, etc.
Sealing materials, stoppers, etc. are injected into the area.

(Problems to be Solved by the Invention) However, when the above-mentioned quick-hardening cement is used as a substitute for earth and sand, the cost is high.Furthermore, when sealing from the outside, there is no problem if there is no seawater, but In general, there is seawater 135 to 2 meters below the seabed even at low tide, so sealing work must be carried out by divers.As a result, it is difficult to do the work (completely sealing is impossible due to gaps in the seawall (concrete)). Joint cracks have various shapes such as vertical, horizontal, diagonal, etc., and widths range from mm to m.These five shapes and various widths make sealing work difficult. It has become difficult.

Furthermore, in the case of polling means, since the gap 6 is not necessarily in a fixed direction and its width is also not constant, it is extremely difficult to cause the polling 8 to reach the gap 6 accurately.

[Means for Solving the Problem] In order to achieve the above-mentioned purpose, in the repair method of the present invention, a hole is drilled from the ground surface into a cavity on the back side of the seawall, and a chemical solution from an injection vibrator is poured into the hole. An injection vibrator is built into the hole so that the discharge port is set at a predetermined position at the gap level, and through the injection vibrator, first the water-absorbing polymer is injected, then the incyanate compound is injected, and then the cement milk is injected. After pouring, backfilling is performed with mortar, earth and sand, etc.

[Effect 1] When each waterproofing material is injected according to the procedure described above, the gel time is short and the injected waterstopping material quickly solidifies. Also,
After the highly expandable water-absorbing polymer once seals the gap, the isocyanate compound, which reacts with water and solidifies with a gel time of 1 to 10 minutes, seals and reinforces the gap. Next, before the gelation of this incyanate compound is completed (during the gelation reaction), cement milk is injected so that the isocyanate compound and cement milk are mixed, and it is made into a material similar to lightweight foaming mortar in terms of strength and physical properties. performance, and water stoppage and backfilling are completely performed. After that, backfilling can be done by pouring concrete, earth and sand on top of it.

[Example] Examples will be described below with reference to the drawings.

In FIG. 1, an injection vibrator 9 is built into a hole drilled from the ground surface toward the cavity 5. This injection vibe 9
The discharge port at the tip is aligned with the level of the gap 6 to be sealed. Then, the injection pump 10 is connected to the injection vibrator 9, and a water-absorbing polymer having a short gel time and high expandability is first injected.Thereby, a water-stopping film is formed in the gap 6, although it is fragile.

Next, an incyanate compound whose gel time is adjusted to 1 to 10 minutes is injected. The injected incyanate compound forms a stronger solidification of 1 m (a solidification layer in which carbon dioxide gas is trapped in the urea gel generated by the reaction with water) with the above-mentioned water stop film as the core. Reinforcement of the blockade will be carried out.

Since the subsequently injected cement milk is injected during the aforementioned gelation reaction, the mixed gel becomes like a lightweight foaming mortar, providing an extremely strong watertight seal.

Then, when the sealing of the gap 6 is completed, backfilling with mortar, earth, etc. is performed. Backfilling at this time is performed with the gap 6 firmly sealed, so that backfilling earth and sand will not flow out.

In addition, when the above-mentioned water stop chemical solution is injected, as shown in the figure, when there are multiple gaps 6, the discharge ports are successively set close together and the injection is performed while refilling. This is a flow chart showing the steps taken.

[Effects of the Invention] As explained above, in the present invention, the drainage material etc. is injected through the hole drilled from the ground side, so the workability is good and repair work can be carried out safely and easily. be able to. In addition, expensive sealing chemicals are effectively used only for sealing gaps, reducing work costs.
I can also do it. Furthermore, since sealing and backfilling are performed at the same time, the construction period can be shortened and construction can be carried out regardless of the presence or absence of seawater.

[Brief explanation of drawings]

1A and 1B are side and front views of a seawall showing the repair method of the present invention, and FIG. 2 is a flowchart showing the procedure of the method of the present invention. On the other hand, FIGS. 3a and 3b show the seawall in a state where the backfilling soil has flowed out, and FIGS. 4a and 4b show the conventional repair method. 1: Paving stone 2: 1i shore block 3: M joint 4: Seawater 5: Cavity 7: Rapid hardening cement. 8: Polling 10: Infusion pump

Claims (1)

[Claims] (1) Drill a hole from the ground surface into a cavity on the back side of the seawall, install an injection pipe into the hole so that the chemical injection port of the injection pipe is set at a predetermined position at the gap level, and insert the injection pipe into the hole. First, a water-absorbing polymer is injected through the gap, then an isocyanate compound is injected, and then cement milk is injected to seal the gap from the inside, and then mortar is backfilled and backfilling is performed with earth and sand. A method for repairing seawalls on coasts, ports, etc., characterized by: