CHAPTER-4
METHOD OF HYDRATION& WORKING
Concrete cloth can be hydrated using saline or non-saline water. The minimum ratio of water to Concrete Cloth is 1:2 by weight. It cannot be over hydrated so an excess is recommended. The recommended methods are: In a hot/arid environment, re-wet the material 2 - 4 hours after the initial hydration.
Immersion:
Immerse Concrete cloth in water for a minimum of 90 seconds.
Spraying:
Spray the dry Concrete cloth with water until it is saturated. Do not use a direct jet of pressurized water as this may wash a channel in the material and create a weakened area.
WORKING
It is bifurcated into four steps
4.1. Unpacking
At the time of installation, CC comes in two forms, Bulk roles or Batched roles (shown in figure)which are flexible in nature.CC is available in two standard roll sizes; bulk rolls or smaller batched, portable rolls the quantity per roll differs between the CC types. Bulk rolls weigh about 1.7 Tons (~3400 lbs.) and are supplied on 6 inch cardboard tubes which can be hung from a spreader beam and unrolled using suitable equipment (see picture below). Bulk rolls provide the fastest method of laying CC and have the additional advantage of reducing the number of joints required.
Batched rolls are supplied on 3 inch inner diameter cardboard cores with carry handles, and can be easily handled by 2 to 4 people. All CC thicknesses can be supplied batched to custom lengths for an additional charge. Bulk rolls are individually wrapped and palletized. All CC rolls are provided with a basic hydration guide placed within the packaging.CC batched rolls are individually wrapped in airtight packaging and palletized. 10 batched rolls fit on a standard 4 x 4 pallet. CC13 is not supplied in a standard batch roll size.
FIG.4.1.1 Batch rolls
(Source: www.concrete canvas.co.uk)
FIG.4.1.2 Bulk rolls
(Source: www.concrete canvas.co.uk)
4.2. Storages
CC should be stored in dry conditions away from direct sunlight and in the manufacturers sealed packaging. If stored correctly CC has a shelf life of 24 months. If stored for longer CC may remain usable in many instances.
4.3. Cutting and Fastening
The cloth is laid on the point of application, cut into proper size and shape, and fastened to the place using staples, Nails and screws.CC A snap off type disposable blade is the most suitable tool for cutting CC before it is hydrated or set. When cutting dry CC, a 3/4 allowance should be left from the cut edge due to lost fill. This can be reduced by wetting the CC prior to cutting. Set CC can be cut as with conventional concrete, with angle grinders, construction disc cutters or tile cutters. CC can also be cut using handheld self-sharpening powered disc cutters. CC sheets in all three thicknesses can also be water cut to a fine resolution. There are a large number of mechanical fasteners that are suitable for use with Concrete Cloth. Some of these fasteners can be used in conjunction with the non-mechanical joining methods described later in this guide to improve the mechanical strength or water proofing properties of joints.
The versatility of CC means that a wide range of manual, electric or gas powered staplers are suitable for attaching CC to soft substrates such as wooden boarding for building cladding. Commercially available hand staplers are suitable for fixing 2 layers of CC together where a small amount of compression force is required - such as with the simple overlap joint described in the CCNon- Mechanical Fastening Techniques section of this brochure. Standard nails can be used to attach CC. Alternatively, a power tool such as the Hilti nail gun, provides a quick and effective method of securing CC to hard surfaces such as concrete or rock. This may be appropriate where CC is being used to recondition an existing concrete surface or for spall lining in mining applications. It is important to ensure that the nail is used with at least a 1/2 washer to ensure the head does not penetrate through the surface of the Cloth. CC fastening using standard nails and electric stapler can be seen in figure given below.
FIG. 4.3.1 CC Fastening using standard nails
(Source: www.concrete canvas.co.uk)
FIG. 4.3.2 CC Fastening using electric stapler
(Source: www.concrete canvas.co.uk)
4.4. Hydrating
After fastening of CC to desired place, it only needs to be hydrated for its final hardening. It is designed in such a way that, it cannot be over hydrated. Only in 24 hours Concrete cloth is ready to serve its purpose.
CHAPTER-5
MARKET AVAILABILITY
Concrete cloth is available in two standard roll sizes; bulk rolls or smaller batched rolls. Bulk rolls provide the fastest method of laying Concrete cloth and have the additional advantage of reducing the number of joints required.
The shelter is supplied folded and sealed in a sack. The 16 m2 variant is light enough to transport in a pickup truck or light aircraft.
There are 3 Concrete cloth types available with the following indicative specifications
5.1. ROAD
Concrete Canvas (CC) provides a durable water management and erosion control solution for new and existing road infrastructure projects. Some specific examples of applications are:
Ditch Lining
Slope Protection
Outfall Protection
CC has quickly gained market acceptance in the civil engineering sector as a cost effective alternative to conventional concrete in ditch lining and slope protection applications.
The speed of installation minimizes traffic disruption and reduces the risks associated with roadside work. CC ditches prevent weed growth and erosion, reducing the maintenance costs associated with unlined ditches, but will naturally ‘green’ over time, helping it blend into the environment.
Existing users of CC in the Rail sector include:
UK Highways Agency
Enterprise Mouchel, UK
Skanska Balfour, UK
Costain, UK
5.2. RAIL
Concrete Canvas (CC) has been used in the rail sector since 2009 and is rapidly establishing itself as the construction material of choice with network providers around the world. Some specific examples of applications are:
Ditch Lining
Slope Protection
The speed and ease of installation means that CC is well suited to time-critical track-side work, vastly reducing line possessions and overall project costs. Eliminating issues associated with rebound from shotcrete means slope protection work can continue without line closures.
The resulting reduction in staffing levels and plant requirement has obvious safety benefits for contractors.
Existing users of CC in the Rail sector include:
UK Network Rail
Canada National Rail
ADIF, Spain
5.3. UTILITIES
Concrete Canvas (CC) is increasingly being used by utilities such as power, waterworks, landfill and hydro-electric companies. Some specific examples of applications are:
Ditch Lining
Slope Protection
Pipe Protection
Cable Covering
CC is increasingly being used as slope protection on sites with sensitive infrastructure such as power stations.
Unlike shotcrete, CC produces no back spray, debris or rebound, eliminating the need for site closures or costly clean-up operations post-installation. Concrete Canvas (CC) can also be used as practical, simple to install coating for pipeline or cable protection.
Existing users of CC in the Utility sector include:
Iberdrola, Qatar
Duncan Mackay & Sons, UK
COMSA EMTE, Spain
Stornaway Council, UK
5.4. MUNICIPAL
Concrete Canvas (CC) has been used on a large range of projects for national governments, public works, councils and local authorities. Some specific examples of applications are:
Gabion Reinforcement
Ditch Lining
Slope Protection
CC has an expected design life of over 50 years and has more than 200 cycles of freeze-thaw testing.
The concrete used within CC is extremely hard wearing and has twice the wear resistance of OPC; as well as excellent resistance to chemical attack and UV degradation.
Existing users of CC in the Municipal sector include:
Caerphilly Council, UK
Ras Al Kaimiah, UAE
Far North Council, New Zealand
Rother Council, UK
5.5. MINING
Concrete Canvas (CC) is being used extensively on large-scale mining projects around the world with customers in South Africa, Canada, Chile, Australia and the UK. Some specific examples of applications are:
Ditch Lining
Vent Walls
Slope Protection
CC cannot be over-hydrated and there is no need for mixing, measuring or compacting on site.CC is well suited to use in extreme environments and has been used installed in environments with sub-zero temperatures such as Northern BC in Canada and at 4000m altitude in the Chilean Andes.
Existing users of CC in the Mining sector include:
Vale, Canada
Barrick, Chile
British Gypsum, UK
Coal Authority, UK
5.6. AGRO
Concrete Canvas (CC) is well suited to agricultural applications where water management and erosion control are key. Some specific examples of applications are:
Remediation
Ditch Lining
Slope Protection
CC also has a low alkaline reserve, a low washout rate and a low carbon footprint, ensuring minimal impact on the environment.
CC can be used to reline existing concrete infrastructure in fisheries, canals or irrigation ditches, allowing time-critical remediation work to be completed quickly and easily.
Mendez Soluciones, Chile
ConcesiónSabana De Occidente, Colombia
OranjeRiet Water Users Association, South Africa
OSEPA Confed. Hidrografica del Ebro, Spain
5.7. PETROCHEMICAL
Concrete Canvas (CC) is increasingly being used by oil and gas companies around the world for a wide range of containment, erosion control and water management applications. Some specific examples of applications are:
Bund Lining
Pipe Protection
Ditch Lining
CC is typically 10 times faster to install than conventional concrete solutions, reducing plant and personnel on site and consequently improving site safety.
CC can also be supplied in batched rolls allowing work to be done in areas with limited access.
Existing users of CC in the Petrochem sector include:
Phillips 66, UK
Petrobras, Brazil
Pacific Rubiales, Colombia
Shell, UK
5.8. DESIGN
Concrete Canvas (CC) has been used by a huge variety of designers, architects and artists. From furniture to conceptual fitness apparatus, sculptures to art installations, CC’s flexibility, durability, ease of use and fabric-like aesthetic has led to it being used in projects worldwide. Some specific examples of applications are:
Furniture
Artistic
Exhibition
Pre-hydrated CC can be cut using hand tools, and the material can be fixed to itself or other surfaces in many different ways.
Set CC can be cut and drilled as with conventional concrete, using angle grinders, construction disc cutters or high-quality tile cutters. It can also be water cut to a fine resolution. CC has excellent drape characteristics, allowing the material to conform to complex shapes, and the fiber surface of CC can be easily painted once set using standard exterior masonry paint.
Existing users of CC in the Design sector include:
Wolfson Design
David Booth
Florian Schmid
Swedish Ninja
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