GEOCONNECT® SHEAR LOAD CONNECTORS FOR STRUCTURAL JOINTS

Our shear load connectors (both for diaphragm wall and slab-slab joints) have a DAU, Document of Assessment for fitness of Use, that is the statement of a favorable opinion on the performances of an innovative product and its intended uses within the field of building and civil engineering construction.

DAU certificates are done and granted by ITeC (the Catalonian Institute of Construction Technology) which, according to the Resolution of Spanish Ministry of Housing from 3 September 2010, is included in the General Register of CTE (Spanish Technical Building Code) Authorized Organisms as an approved body for the granting of DAU as technical assessment for innovative products and systems.

FISUFOR® PLUG - Masonry reinforcement with overlap without manipulation

fisufor® plug has an innovative design that makes it possible to achieve the overlap between reinforcement without the need for manipulation, keeping the area of the overlap the same nominal width of the reinforcement.

The ends of the fisufor® plug pieces have a special geometric configuration in the form of a plug that allows the overlap of 250mm without having to cut any wire.

Also, the transverse wire in this area is flattened in order to guarantee the minimum coating of mortar.

ADVANTAGES

• Increases resistance to bending in the wall.
• Guarantees the correct transmission of forces.
• Overlap without any manipulation.

 

WHAT ARE THE MINIMUM COVERINGS OF THE REINFORCEMENT?

The upper and lower mortar coverings should be no less than 5mm.

It is very important to comply with the Eurocode, this is the constant coating over the reinforcement.

Lateral mortar coatings should not be less than 15mm, in this case also be constant all along the reinforcement, including the area of overlap.

AREN’T DIFFERENT REINFORCEMENTS REALLY EQUIVALENT?

As a general example to meet the minimum amounts required in the Eurocode to achieve a masonry assembled for the purpose of reducing cracking, it is sufficient to place masonry reinforcement of 3mm Ø ev ery 60cm.

I WANT TO BUILD MY WALLS TO PREVENT CRACKING, HOW MUCH REINFORCEMENT SHOULD I PUT?

The Eurocode explicitly defines the minimum amount of reinforcement needed to give ductility to the masonry and prevent cracking. In this sense, it determines the vertical separation between reinforced rows will not surpass 60cm and the area of steel will not be less than 0.03% of the area of the wall. The measure is preventative, and given that it is explicitly stated in the Eurocode it can help deal with the civil responsibility derived from pathological processes produced by cracking in the walls. However this measure by itself does not guarantee 100% of the absence of fissures. What is really effective to avoid cracking is a good constructive design solution to avoid risk situations.

HOW TO EXECUTE A CORRECT OVERLAP?

1. Cut one of the longitudinal wires.

2. The length of overlap for masonry reinforcement should be at least 250 mm and the separation between longitudinal wires ≥ 20 mm

In accordance with the specifications of the current standards, a correct overlap between truss type masonry reinforcement should meet the following requirements: Length of overlap: 250 mm (0,6 the distance of the pitch of the cross-wires). Horizontal distance between overlapped wires: 20 mm.

Lateral coating of the wires that have been cut: 30 mm (except stainless steel wires).

The “plug structure” of the geofor® reinforcement ensures all these requirements without any need for manipulation by the operator.

 

 

IMPORTANT: At the ends of the reinforcement for structural use it must meet the tree requirements: ADHESION, MORTAR COATING and OVERLAP.

 

WHY IS IT IMPERATIVE TO HAVE THE CE MARKING?

Firstly because it is compulsory for the products that are incorporated in the construction of a building. Secondly because the CE marking, carried out within the existing legal framework along with the implementation of the Eurocode are the only quality assurance (of the State not the supplier). It is also the only way of checking that incorporated products in walls have the same benefits stated in calculations. There is no point calculating if there is no comparison value for gauging.

TO IMPROVE THE PERFORMANCE OF MY WALL IN SEISMIC EVENTS,WILL I NEED TO PUT ALOT OF BED JOINT REINFORCEMENT?

For seismic events, the reinforcement itself will improve the mechanical behaviour of the wall because of its ductile properties. However for the same reasons given previously, this cannot be assigned stability of the wall to the reinforcement itself.

 

For the reinforcement to be calculated into seismic effects, it should be accompanied by other elements of retention, such as anchors to the pillars.

corner execution

DOES THE WIDTH OF THE REINFORCEMENT BENEFICIALLY AFFECT THE STRUCTURAL PERFORMANCE?

Reinforcement used in crack control does not require a specific width, since the only thing that counts in this case is the area of steel section.

By contrast, the width of the reinforcement has a role to play when it has a structural function, and that by increasing the mechanical arm, you increase at the same proportion the horizontal bending strength of the walls in the masonry.

DOES CORRUGATED WIRE IMPROVE THE ADHESION?

The reinforcement does not improve at all by the fact the wire is corrugated. The conditions for grip relating to transferring forces evenly through-out small-diameter bars, such as the type of masonry reinforcement depend more on the measure of mortar and not the masonry reinforcement.

Grip provided by corrugated bars is only needed when the forces you may have are very large, this only occurs within very thick bars. In the case of the reinforcement a number is worth a thousand words, two bars of 4mm in diameter can transfer securely 10kN, following the required regulations.

This value has been tested on smooth bars of reinforcement. Furthermore the calculation shows the real value of the force that is transferred across the reinforcement (that is met by the minimum quantity requirements) in worst case scenarios, is approximately half.

Consequently the corrugated reinforcement makes no extra benefits of reinforcement that weren’t in the traditional reinforcement. It is important that the technique of reinforced concrete, capable of transferring large forces, use normal plain bars when there is a small diameter. What really improves the transmission of forces is the existence of a suitable cover of reinforcement in the overlap areas.

 

 

 

 

DOES AN INCREASE IN THE STRENGTH OF THE STEEL THAT IS USED IN THE REINFORCEMENT IMPROVE THE MECHANICAL BEHAVIOR OF THE WALL?

For control of cracking, the strength of the steel in the reinforcement has no influence on the amount of reinforcement needed, only the area of the crosssection.

When the reinforcement is assigned a structural role, the fact the steel is stronger, does not mean necessarily that you reduce the amount of reinforcement in the same proportions. Because by the requirements of the minimum amount, in the vast majority of cases, steel does not display even half of the resistance. It is the parameter of steel reinforcement which really improves the mechanical performance in the wall, on account of its ductility, not of the resistance.

For this reason, to prevent cracking and for the transmission of forces it is preferable that the steel has a high percentage of deformation at failure (that is the parameter which determines ductility) than high resistance.

Ghas system

AS I HAVE BUILT MY WALL VERY HIGH, WILL IT NEED A LOT OF REINFORCEMENT?

The reinforcement is not an element of retention, a wall with lots of reinforcement if it is not sufficiently connected to the structure may fall in its entirety. The masonry reinforcement does not provide stability itself. The reinforcement is there to provide ductility and therefore significantly reducing the risk of cracking. When assigning the reinforcement a mission to structurally support, it is imperative that the wall and support pillars and connected by anchors.

WELCOME TO THE STEEL FOR BRICKS BLOG

Steel For Bricks GZ, S.L. welcomes you to its new blog where we will share our experience of more than 20 years in the construction sector.

We belong to the GZ group, composed of companies:

• ZFoam (specialist in fabricating plastics)
• Geohidrol (construction systems for civil engineering and construction)
• TecnoGZ (acoustic insulating materials in construction)

SFB products for reinforcement of masonry have the CE marking and are according to the new technical building code applicable today, the part relating to factories (walls made of ceramic brick or block of concrete according to the document basic DB-is-F).

In this blog we discuss:

•New products
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•Internationalization