JPS63138098A - Secondary lining structure of concrete segment inner surface - 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] [Industrial Field of Application] The present invention is widely used in underground passages such as subways, public drains installed underground, power, communication cables, gas, public water and sewage pipes, etc. This relates to the internal secondary covering structure of the concrete segment.

[Conventional technology]

In underground communal ditches etc. excavated by shield machines etc., concrete segments divided into several parts are assembled on site and used as the inner surface structure of the communal ditch etc. in order to prevent earth and sand from collapsing.

Concrete segments are precast, pressurized, and steam-cured high-strength reinforced concrete, but the best way to assemble them is to use bolts and nuts to fasten metal fittings that have been buried in predetermined locations in the concrete segments. It is being

Therefore, it is necessary to prevent corrosion of these fastened parts, and for the purpose of preventing water leakage, preventing condensed water from entering, improving the aesthetic appearance of the finish, and obtaining smoothness, a secondary wrapping of mortar is applied to the inner surface of the concrete segment after assembly. ing.

In this secondary winding process, a formwork is constructed on-site to obtain a secondary winding of 2001111~300 mW on the inner surface of the concrete segment, and mortar is poured into the space created between this formwork and the inner surface of the concrete segment. The method used was pouring on-site.

[Problem that the invention seeks to solve]

As mentioned above, concrete segments are made of precast pressurized and steam-cured high-strength reinforced concrete, whereas secondary-wound mortar is cast on-site.
There is a problem that adhesion between the two tends to be poor, and over time, cranks occur on the mortar surface of the secondary reinforcing layer, and the secondary reinforcing layer gradually peels off.

Another problem is that when air enters the recesses for connecting bolts between concrete segments, the recesses tend to be filled with mortar insufficiently, which leads to corrosion from that area and a decrease in the strength of the joints of the concrete segments. was there. In addition, it requires a lot of time and effort to assemble the formwork, pressurize the mortar, and remove the formwork after hardening on site, resulting in poor workability.

Furthermore, in order to suppress the deterioration of the secondary reinforcing layer over time, the secondary winding is formed on the inner surface of the concrete segment to a thickness of 200 to 300 mm, which poses the serious problem of significantly reducing the effective volume of common ditches, etc. Means for Solving Problem C] The object of the present invention is to eliminate the problems of the conventional secondary winding structure on the inner surface of concrete segments, and to In addition to filling the kneaded quick-drying resin mortar, a resin mortar containing carbon fiber is applied to the inner peripheral surface of the concrete segment to a thickness of 7 um to 1 um by using a mortar lining machine.
An object of the present invention is to provide a secondary ring structure on the inner surface of a concrete segment formed with a thickness of 0.011 mm.

To explain in detail the configuration of the present invention for solving the problem, quick-drying resin mortar is filled in the recesses for bolt fastening in the joining parts of concrete segments, and the inside of the joined concrete segments is filled with quick-drying resin mortar. A secondary ring structure on the inner surface of a concrete segment characterized by forming a coating layer of resin mortar containing carbon fiber as a reinforcing material on the circumferential surface with a thickness of 7 to 10n+. The reinforcing layer is efficiently constructed using a mortar lining machine that travels inside the pipe and radiates resin mortar onto the inner surface of the concrete segment using centrifugal force.

〔Example〕

Hereinafter, a specific configuration of the present invention will be explained in detail based on illustrated embodiments.

Figure 1 is a plan view of the joint between concrete segments, Figure 2 is an enlarged sectional view taken along line nn in Figure 1,
FIG. 3 is a side view showing an example of a mortar lining machine, and 1 in the figure indicates a concrete segment.

Concrete segment 1 is divided into several parts, depending on the size of the underground common ditch, etc., and can be assembled on site. Concrete segments are placed on both longitudinal and widthwise edges. A recess 2 for bolt fastening is provided for connecting two pieces together. A fastening hardware 3 is buried in this recess 2 in advance, and after the hardware 3 are brought into contact with each other, a bolt 4 is drilled in the hardware 3, passed through the through hole, and then screwed together with a nut 5. A sealing material 6 made of synthetic rubber or the like is sealed in the gap between adjacent concrete segments 1.

This recess 2 for bolt fastening is used for bolts 4 and hardware 3.
In order to prevent corrosion, filler (resin mortar) with the following composition is filled to make the surface smooth.

Filler (resin mortar) composition Powder components> Ultra-rapid hardening cement) 29.4 to 60.0 parts by weight Portland cement 70.0 to 313.5
//Alunite 0.0~0.6〃
Styrofoam powder 0.5-0.7 Anti-sag agent 0.1-0.2 These powder components are uniformly stirred and mixed with a mortar mixer,
Add 30 to 80 parts of the following liquid component to 70 to 80 parts of the powder component.
-20 parts are added and both are thoroughly kneaded.

<Liquid component> Water-soluble rust preventive agent 3.0 parts by weight Acrylic emulsion 3B, 0 Water
58.0 〃Silicone antifoaming agent 1.0〃 In addition, when filling the resin mortar 7 into the recess 2, remove the rust adhering to the hardware 3 and bolts 4 and the efflorescence adhering inside the recess 2. (calcium hydroxide) etc. using a wire brush or the like, and after uniformly applying the liquid component as a wetting primer to the surface with a brush, resin mortar 7 is filled using a plastering trowel or the like,
Finish the work by making the surface smooth.

The resin mortar 7 having the above composition solidifies in 60 to 90 minutes after filling. It goes without saying that the resin mortar 7 is also filled into drain cocks and the like provided in the concrete segment 1.

Next, a coating layer 8 of resin mortar containing carbon fiber as a reinforcing material is formed on the inner circumferential surface of the joined concrete segments 1 to a thickness of 7 fl to 10 mm. , the resin mortar forming layer 8 contains 100 ft of ordinary Portland cement as a powder component (200 parts by weight of silica sand as a fine aggregate, 1 part by weight of silica sand as a fine aggregate, 1 part by weight of carbon fiber)
It contains 4 to 5 parts by weight and additives, and after mixing these thoroughly with a cement mixer, 80 to 70 parts of the powder component is added to 20 to 30 parts of the liquid component shown below, and both are mixed. Knead well.

<Liquid component> Acrylic emulsion 40 parts by weight water
59 Water-soluble antifoaming agent
l This secondary winding process is performed in the following order.

First, the efflorescence and laitance adhering to the inner surface of the concrete segment 1 are removed and cleaned using a wire brush and a Sangu. Note that a pipe inner surface cleaning machine can be used for this surface treatment.

After the surface treatment is completed, the above-mentioned liquid component as a wetting brusher is uniformly applied to the inner surface of the concrete segment 1 by spraying or brushing. The appropriate amount is approximately 0.2 kg per 1% concrete segment.

Next, a mortar lining machine 9 as shown in FIG. 3 is carried into the pipeline from the working shaft, and while the lining machine 9 is running to the left in FIG. The direction is sprayed on the inside,
A coating layer 8 of a predetermined thickness is formed on the inner surface of the concrete segment 1. In addition, in FIG. 3, 12 is a motor for rotating the spinner 10, 13 is a running vehicle equipped with a running motor and control equipment for the lining machine body, 14 is a running wheel, 15 is a trowel device, and 16 is a trowel device. A reducer 17 for the trowel device indicates a mortar supply pipe.

The thickness of the coating layer 8 is formed to an arbitrary thickness in the range of 7 tm to 10 tm depending on the discharge amount of the resin mortar 11 from the spinner 10, the running speed of the lining machine body 9, the length adjustment of the trowel device 15, etc. It is something that can be done.

〔Effect of the invention〕

The present invention has the above-mentioned configuration, and since the resin mortar is filled in the recesses for bolt fastening in the joining parts of concrete segments, corrosion from this part can be effectively prevented, unlike the conventional method. This solves the problem that the strength deteriorates over time because there is no room for air to enter the recess. In addition, unlike conventional secondary winding by casting mortar on-site, there is no need to assemble formwork in a common ditch, etc., making it extremely easy to construct.
Since the coating layer is formed with a thickness of about ~100 mph, it is possible to solve the problem of reducing the effective use of the pipe space.Moreover, the coating layer contains carbon fiber as a reinforcing material. Because of this, no cranking or peeling phenomenon occurs, and it is possible to effectively prevent the secondary reinforcing layer from falling off.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a connecting portion of concrete segments, FIG. 2 is an enlarged sectional view taken along line Ifn in FIG. 1, and FIG. 3 is a side view showing an example of a mortar lining machine. 1: Concrete segment 2: Recess 3: Hardware 4: Bolt 5: Nut 7: Resin mortar 8: Coating layer Patent applicant Yatomi Shokai Co., Ltd. Figure 1

Claims (1)

[Claims] Quick-drying resin mortar is filled in the recesses for bolt fastening at the joints of concrete segments, and resin mortar containing carbon fiber as a reinforcing material is used on the inner peripheral surface of the joined concrete segments. A secondary covering structure for the inner surface of a concrete segment, characterized by forming a covering layer with a thickness of 7 mm to 10 mm.