Steel wire woven HardTape for construction reinforcement

Introduction

High-tensile steel wire woven tape for construction reinforcement( HardTape) is made by Zhengzhou HardTape New Materials Technology Co.,Ltd(China) according to the Patent No.ZL 2018 1137 4053.4

The main material is hot-coated galvanized steel cord with the construction of 3+2,tensile strength over 3000MPa,high adhesion with construction motar,different density can easily match with different grain size of motar.this steel wire tape is best choice of construction reinforcement materials,better than usual carbon fibe sheet or carbon fiber resin board with easy engineering,long-life and fire resistant.

Unidirectional, extra-high strength galvanized steel cord knitted tapes/fabrics, made of steel cords, fibre glass and other fibers. Steel cord knitted HardTape is specific for use in structural strengthening in combination with  mineral matrices or organic matrix according to project and site requirements. Thanks to its characteristics HardTape is easy to shape and has excellent installation and durability properties. HardTapes guarantee superior properties than traditional carbon-glass-aramide fibre textiles, and are particularly effective in various structural strengthening and anti-seismic improvement or compliance operations, as well as in the creation of connection systems

Advantages

1. High durability thanks to the special steel wire galvanisation process
2. Certified for use in structural strengthening in combination with mineral matrices and epoxy matrix
3. Can be tensioned for structural strengthening and active devices
4. Easy to shape using the benders

Areas of application

Intended use:

• - Static and seismic upgrade or retrofit of masonry in brick, natural stone and tuff, reinforced concrete, prestressed reinforced concrete, wood and steel；
• - Consolidation of brick masonry, natural stone and tuff arches, vaults and domes
• - Confinement and wrapping of masonry and reinforced concrete structural elements
• - Flexural, shear, and confinement strengthening of brick, natural stone, tuff, and masonry panels and reinforced concrete sections
• - Flexural, shear, and confinement strengthening for timber elements
• - Flexural strengthening for steel girders
• - Execution of top ring beams in reinforced masonry
• - Execution of special single- or double-fibre thread connectors for anchoring sheets and grids and executing reinforced injections
• - Consolidation and strengthening of exposed stone walls using widespread insertion of mesh

Instructions for use

Preparation

The ultra-high strength galvanized steel cord woven tape HardTape, is ready-to-use. The HardTape can be cut at right angles to the cords with manual or electric shears, or parallel with the cords using a normal box cutter.

The HardTape, cut into strips even just a few cm wide and a number of metres long, ensures perfect stability without in any way compromising the workability of the material and its application.

 Preparation of substrates

The substrate must be properly prepared and cleaned, always in accordance with the instructions dictated by the construction supervisor .In the case of substrates that are not degraded, prepare the surfaces as indicated in the technical data sheet for relevant mortar materials. When the substrate is clearly degraded, uneven, or damaged by significant events, proceed as follows, always in accordance with the construction supervisor:

 1. For masonry, tuff and natural stone substrates:

• - Completely remove residues from previous processes that could compromise adhesion, and any quantity of inconsistent rendering mortars from the stones; Saturation, spray, or brush application, if required, of certified natural stabilizing cortical consolidant with base of pure stabilised potassium silicate in aqueous solution such as Biocalce Silicato Consolidante or water-based eco-friendly solvent-free stabilizing agent, such as Rasobuild Eco Consolidante;
• - Reconstruction, if necessary, of material continuity according to design instructions and the construction supervisor. Evening out previously consolidated surfaces with structural geo-mortar with a base of pure natural hydraulic lime NHL 3.5 and geo-binder depending on the thickness required;
• - When applying the reinforcing system with an inorganic matrix, make sure that the substrate is adequately dampened and with a roughness of at least 5 mm,  for preparation of reinforced concrete and masonry substrates .

 2. For substrates in reinforced concrete or prestressed reinforced concrete:

• - Thorough removal of weakened concrete if necessary, through mechanical scarification or hydro-demolition, making sure to roughen the substrate to a depth of:
• - at least 5 mm, for preparation of reinforced concrete and masonry substrates”, if the strengthening system is applied with  inorganic matrix;
• - at least 0.5 mm,  for preparation of reinforced concrete and masonry substrates”, if the strengthening system is applied with  epoxy mineral matrix.
• - Removal of rust, if any, from reinforcing bars, which must be cleaned by brushing (manual or mechanical) or sandblasting;
• - Monolithic reconstruction or smoothing of the section, if needed, using geo-mortar based on a mineral geo-binder .

Application

Execution of the structural strengthening Steel Reinforced Grout (a combination of steel cord woven HardTape  and Antisismico  mortar) or Steel Reinforced Polymer (a combination of the HardTape and epoxy mineral matrix) will be carried out, in case of mineral matrix, by applying a first coat of geo-mortar.

Make sure there is sufficient material for the substrate (average thickness ≈ 3-5 mm) to even it out and to lay and embed the strengthening HardTape. When using an epoxy mineral adhesive matrix on substrates in reinforced concrete, the substrate can be evened out using mortar, taking care to allow the geo-mortar to cure for long enough to ensure that the humidity of the substrate is appropriate for application of mortar.

Before application of the first layer of mortar, the substrate must be clean, dry, free from damp and roughened, by sanding or mechanical scarification, to a depth of at least 0.5 mm, for preparation of reinforced concrete and masonry.

The first layer of adhesive must be an average thickness of ≈ 2 - 3 mm. Afterward, working over the matrix while it is still wet, apply the ultra-high strength galvanized steel cord woven HardTape, making sure that the HardTape is perfectly incorporated into the matrix by pressing with a spreader or steel roller, and also checking that it comes out between the cords to ensure optimum adhesion between the  first and second layers of matrix.

At longitudinal overlapping points, overlay two layers of steel cord HardTape by least 20 cm for epoxy matrix and 30 cm for inorganic matrices. For organic and inorganic matrix, working fresh on fresh, perform the final protective smoothing (overall thickness of the reinforcement for organic matrix ≈ 3-4 mm, overall thickness of the reinforcement for mineral matrix ≈ 5-8 mm), in order to fully incorporate the reinforcement and fill in any underlying voids.

If there are additional layers after the first, proceed with laying of the second layer of steel cord HardTape over the matrix while it is still wet, repeating the steps described above.

 In the event that the system installed with epoxy matrix must be plastered or concealed by smoothing, we recommend that, while the resin is still wet, you apply a spray of mineral quartz to provide better adhesion for subsequent layers.

 If the reinforcing system is installed in especially aggressive environments, or you otherwise wish to ensure additional protection beyond that already provided by the matrix, we recommend applying:

 If the works are in permanent or occasional contact with water, the cycles described above must be replaced with a polyurethane epoxy cycle or an osmotic cement depending on the needs of the worksite and the design specifications.

For technical specifications, application, and preparation of the matrix, as well as protective systems adequate for the matrix type, consult the relevant data sheets。

Abstract

Steel cord woven Hardtape reinforcement system for construction engineerings.

 Execution of repair, structural strengthening, improvement or seismic upgrade of masonry, tuff or natural stone elements and structures using an inorganic matrix composite system, steel cord woven HardTape system for construction reinforcement

SRG composed of unidirectional, extra-high strength galvanized steel cord woven HardTape, made of steel cords compliant with standard ISO 16120-1/4 2017 knitted with fibreglass and other fibers materials,

– with the HardTape featuring the following certified technical characteristics:

tensile strength, characteristic value > 3000 MPa;

modulus of elasticity > 201 GPa;

no. cords per cm  from 1.0 to 8 piecess(depending on the specifications), with wire winding at high torque angle, compliant with standard ISO/DIS 17832;

To be applied directly to the structure requiring strengthening. The procedure is conducted as follows:

1. Any restoration of degraded, weakened, non-cohesive, or non-planar surfaces, using relevant geo-binders and in any case as prescribed and approved by the construction supervisor;
2. Preparation of the substrate for application of the first layer of geo-binders, the substrate must be adequately roughened by sanding or mechanical scarification, taking care to guarantee a roughness of at least 5 mm , clean and dampened;
3.  Lay a first layer, an average of ≈ 3-5 mm thick of fine-grain, structural, geo-mortar with pure natural hydraulic lime NHL 3.5 and geo-binder base;
4. While the mortar is still wet, lay the ultra-high strength galvanized steel cord woven HardTape, and by pressing firmly with a smooth spreader or metal roller, make sure that the HardTape is completely impregnated and avoid allowing any gaps or air bubbles to form, because these can compromise the adhesion of the HardTape to the matrix or to the substrate;
5. Working fresh on fresh, apply the second layer of structural geo-mortar, until the reinforcing HardTape is fully incorporated and any underlying voids are filled, giving an overall reinforcement thickness of ≈ 5-8 mm;
6. Repeat steps (4) and (5) if necessary for all subsequent reinforcing layers called for by the design;

Main property of steel wire woven tape for reinforcement

Technical Data compliant with HardTape Quality Standard

Cord 3+2 obtained by joining 5 filaments, of which 3 straight and 2 wrapped with a high torque angle:

• - tensile breaking load of a cord > 1600 N
• - tensile strength of the sheet, characteristic value > 3000 MPa
• - normal elastic modulus of sheet, average value > 201 GPa
• - break warp of the sheet, characteristic value > 1,5%
• - Equivalent thickness t ≈ 0,084 mm

INSTALLATION CONDITIONS

•  Maximum temperature (air and substrate)-- < +35 °C
•  Minimum temperature (air and substrate)-- > +5 °C
• Relative air humidity-- irrelevant Moisture of the substrate (gluing surface)-- saturated substrate with no excess water。

SERVICE CONDITIONS

•  Maximum temperature (air and substrate)-- < +80 °C
•  Minimum temperature (air and substrate)-- > -40 °C
• Relative air humidity—irrelevant
•  Contact with water²-- occasional
•  Reaction to fire³    -class A1

In the presence of installation and working temperatures outside the limits indicated above, contact the  technical department to provide for suitable protective systems for application and operation of the steel cord woven HardTape SRG reinforcement system.

1.  The performance characteristics of the HardTape SRG system are compliant with and calculated as foreseen by the Guideline for the identification, qualification and acceptance testing of fibre reinforced composite materials with an inorganic matrix (FRCM) , for use in the structural consolidation of existing buildings, published by our technical department.
2. In the event of permanent contact with liquids, contact the HardTape technical department to provide for the most suitable protective system.
3. In case of exposure to fire load, or fire resistance, protect the HardTape SRG reinforcement system by means of an appropriate certified system.

Warning

• -Product for professional use
• -abide by any standards and national regulations
• -when handling the steel cord HardTape wear protective clothing and goggles, and follow the instructions regarding methods for applying the material
• -contact with the skin: no special measures required
• -storage on the work site: store under cover in a dry place, well away from substances that might damage it or its ability to adhere to the chosen matrix system
• - the product is an item according to the definitions of the EC Regulation No. 1907/2006 and therefore does not require a Safety Data Sheet
• -for any other issues, contact the HardTape company

Product test report

Products pictures