What is TACOM, a concrete “fabric formwork” that drastically shortens the construction period for slope protection work?

台風や豪雨の季節になると、山岳部などで土砂災害が発生します。
この復旧には、コンクリートやモルタルを打設する法面保護工などが必要になりますが、現場の条件や状態によっては、従来の木工法を用いた工事が困難なケースがあります。

そんな場面で活躍するのが、布製型枠『タコム』です。

場所を選ばずどこへでも簡単に持ち運びでき、敷設が可能で、特殊機械や技能、型枠工なども不要のこの工法は、既に各地の法面工事で採用されています。仮復旧ではなく本復旧が可能な工法として、多くの優れた実績を残しています。

この記事では、布製型枠『タコム』の概要を紹介し、メリット・施工手順と合わせて現場事例を多数ご紹介します。
台風や豪雨の季節に向けて、とくに自治体の土木担当の方などに参考になる内容です。

What is fabric formwork "Tacom"?

Fabric formwork “Tacom” is a synthetic fiber bag-shaped mat that can be injected with fresh concrete or mortar to easily and quickly form a concrete surface of a certain thickness. The mat is lightweight, compact, and flexible, and can be laid in half to one day, regardless of location. Since no special machinery, skills, or preparation is required, the most significant feature of this product is that the construction period can be significantly shortened compared to conventional wooden formwork.

 

There are two types of mat shapes: “standard (non-filter) type” and “filter type. Each has the following different features, allowing you to choose the type best suited to your site conditions and application.

 

Standard (non-filter) type

It is the most versatile type and can form an all-surface concrete (mortar) board of a certain thickness.

 

Filter type

The filter type, which has a gap at the bottom of the sheet, is suitable for slopes with spring water and regulating reservoirs with a difference in water level, and can drain spring water from the slope smoothly.

 

Dimensions are factory-processed to suit the site, and a wide range of thickness standards from 5 cm to 50 cm are available, allowing for flexible adaptation to the application and site. Usage Types by Main Applications

This method can also be applied underwater, and is ideal for river slope protection, three-surface channel construction, revetment protection, and covering of sandbag piles. Click on the link below to watch a detailed video.

 

 

 

（１）上記配合は、骨材別途の標準です。特に水中施工の場合は、材料の分離に対して注意が必要です。
（２）施工前に必ず試験練りを行ってください。
（３）コンクリートの配合には混合材料の使用を推奨します。
（４）脱水量はモルタル１５％、コンクリート（20～25㎜）７％程度です。 この記事の後半で紹介するように、既に多くの現場で採用された実績があります。 関連情報：法面保護に関する資料をダウンロード

Features and advantages of fabric formwork "Tacom

The fabric formwork “TACOM” is especially effective for three-sided channel construction in narrow sites such as mountainous waterways.

 

Its features and benefits are as follows

• Flexible and short construction period (daily construction volume: approx. 300-500m2)
• Versatility in any location (can be installed with piping)
• High durability
• Economical (50H (5cm thick) approx. 6,000 yen/m2 or thereabouts)
• No need for heavy equipment, can be transported by human power

 

Flexible and short construction period

Concrete (mortar) can be poured simply by laying the mats on site and securing their perimeter. Laying of the mats can be completed in half a day to one day, even over a large area, allowing for installation by a small number of people and in a short period of time.

 

Large heavy machinery is not required, and construction can be performed underwater or subsea.

 

Diversity in any location

The mats are lightweight, compact, and flexible, and can be installed in any location compared to conventional construction methods such as wooden formwork and taut blocks.

 

Since the shape is factory-processed to suit the site, it adapts well to various ground irregularities and can be installed in a wide variety of shapes. The maximum applicable slope is about 1:10.

 

High durability

Compared to conventional concrete block stretchers, the mat has a large surface area, making it highly durable against waves and water currents.

Construction procedure for fabric formwork "Tacom

The installation procedure for fabric formwork “Tacom” is extremely simple. No special machinery, skills, or skilled formworkers are required. The concrete surface can be formed simply by laying (fixing), pouring, and washing mats on site. The construction procedure is as follows

1. reserve
2. Laying and fixing mats
3. injector
4. cleaner

1. Preparation

• Cut and fill is performed based on the plan (design), and machine shaping is performed.
• As a human finish, the unevenness of the ground is evened out and trees and roots are removed.
• When the bottom of the slope is underwater and the depth is more than 50 cm, the flow velocity is controlled within 0.2 m/s.

 

2. Laying and fixing mats

• Check the construction area and lay the mat on the slope.
• Select a place with good footholds and pass a single pipe through the upper part of the slope.
• The extension direction is assembled to the specified dimensions to account for shrinkage of the mat and secured with chain blocks for support.

3. Injection works

• A hose is inserted into the mat’s inlet and concrete/mortar is poured.
• Always install with care so that the end of the injection hose is positioned inside the concrete, and inject from a low position.

4. Cleaning work

• The inlet is treated by smoothing the protruding inlet for aesthetics.
• Wash with water any concrete or mortar spilled during pouring.
• The construction is completed with the removal of the sub-materials used.

 

Related information: Download Slope Protection Resources

Example of construction of fabric formwork "Tacom

The fabric formwork “TACOM” has been adopted by many municipalities as a means of restoration in disaster restoration work on mountain waterways. The following are five examples of TACOM construction that demonstrate its superior effectiveness, especially in three-sided waterway construction.

• Ryujin Skyline Line Restoration and Rehabilitation Project
• Forest Road Taniguchi Minasegawa Line Disaster Restoration Work
• Forest road disaster restoration project (Forest road Hoi Hoi Slope line)
• Forest road Buzumiya line prefectural land disaster prevention measures mountain control project
• Slope protection work] Green Pier adjustment pond restoration work

 

Road rehabilitation: Road rehabilitation, erosion control project

施工場所	和歌山県新宮市熊野川町
Part No.	TACOM Standard Type 100H / Standard Type 150H
Quantity	147m2 / 13m2

The slope along the road collapsed due to a typhoon, and early restoration was essential to prevent secondary disasters, so TACOM, which does not require wooden formwork and is fast-acting, was selected.

 

Forest road disaster restoration work

施工場所	和歌山県田辺市
Part No.	TACOM Standard Model 200H
Quantity	177m2

TACOM was selected for a forest road channel near the Taniguchi Minasegawa line of forest roads because of its superior durability and stability over corrugated pipes.

 

Forest road disaster restoration project

施工場所	和歌山県新宮市熊野川町
Part No.	TACOM Standard Type 300H
Quantity	550m2

Water overflowed from the existing channel, and the back side of the downstream channel eroded and collapsed from the overflow point. TACOM was selected for its durability over the long term to prevent collapse even if the water overflowed again.

 

Forest Roads: Prefectural Land Disaster Prevention Measures, Mountain Reclamation Project

施工場所	和歌山県田辺市
Part No.	TACOM Standard Type 150H
Quantity	250m2

TACOM was used for channel construction that collapsed due to heavy rains, because it can be constructed in accordance with the topography, does not require formwork, and is fast-acting.

 

Slope protection work] Regulating reservoir restoration work

施工場所	岐阜県恵那市
Part No.	TACOM Standard Model 200H
Quantity	480m2

The slope behind the regulating reservoir had been protected by a block pile, but collapsed due to rainwater entering from the slope drainage channel during a heavy rainfall event. TACOM, which requires no formwork and is fast-acting, was used for the restoration of this slope.

summary

As a method for the main restoration of landslides caused by typhoons and torrential rains, the “TACOM” fabric formwork method was introduced.

• The site is too small for large heavy machinery to enter.
• Difficult to arrange skilled workers to assemble wooden formwork
• Shortened construction period due to urgent need for restoration

Please consider fabric formwork as a solution for river slope protection, three-sided channel construction, revetment protection, and sandbag covering. For further information and inquiries about fabric formwork “TACOM”, please refer to the following link.

> “Cloth Formwork Tacom” by Taiyo Kogyo Co.

>> Click here to contact us.