WeatherSolve Advantages

WeatherSolve Advantages

At WeatherSolve we have been researching, developing, designing, and building wind fences for over 30 years.  WSS has miles of fences close to 100ft high in North and South America and in the Middle East plus many fences around 60ft high. We have similar fences in Asia and the South Pacific. We know of no other companies with wind fences still standing that are over 60ft high. In fact no other company has even a small fraction of this experience – in length, in height or in variety of locations.

We are sometimes asked what is the difference between our fences and others. These pages are to answer that question. If you have questions, please contact us – we are here to help.

1.       Cost of poles.

Poles are around 80% of the cost of tall windbreaks. A pole that is twice as strong uses little more labour and only about 50% more materials (including foundation materials) so it makes economic sense to space them a good distance apart.

The unique WSS cable support system facilitates very large spacings (100ft is common, we have done 120ft.) This can result in substantial savings for the total project.

The fabrics we use are mostly woven polypropylene. This fabric spans the short (up to 12ft) vertical distance between cables. As the fabric-span distances are not large the tensions in the fabric are kept to reasonable levels – even in extreme storms.

Other wind fence systems tend to space poles at about 20ft.  One example is the Koch system which is an excellent cladding material for short spans. It is engineered to span from pole to pole with fabric alone. Usual Koch installations set the maximum pole spacing at 15ft to 20ft for their standard fabric (which is about 75% solid) in a non-extreme storm environment. This is because the fabric spans between poles with no other support so fabric strength and clamping system strength limits the span for any given design windspeed. For lighter fabric the fabric is disproportionally weaker as the only way to make a more porous knitted fabric is to use a lot less yarns. In knitted fabric the same yarns run both vertically and horizontally in a stair pattern so the maximum span of lighter fabric is even less.

2.       Safety in storm conditions

The nature of wind and probability is that sooner or later an extreme storm will occur that exceeds the design load. The question then becomes what (if anything) breaks and the consequences of those breaks.

WeatherSolve windbreaks are unique in many ways, and one of those ways is a stress release system which can be set to any design load. It is designed to release the lower edges of the fabric panels before cables or poles break. The top edge has a much stronger attachment system and remains in place. This keeps the fabric attached to the structure even in hurricane force winds when other debris is blowing around that might puncture or overload the fence.

For all other systems without a stress release, when fabric breaks away in an uncontrolled manner it can break completely free of the fence. These pieces of fabric can then get entangled in machinery or blow across roads creating a safety hazard. If the fabric does not break away the load on the poles could be such as to cause a pole to be blown over in hurricane winds which would obviously be a large danger as well as a large cost to repair.

People ask about the danger of breaking cables, but actually the danger is minimal compared to the above dangers. The cables are securely shackled to at least one piece of fabric (via the top edge of the fabric which does not break loose) so the cable is not free to flap around. In addition the cables are firmly clamped at each pole so the longest piece of potentially loose cable is the pole spacing.

3.       Experience with tall windbreaks.

When putting a sail up to 100ft  (30m) in the air the wind loadings are very large and there are many subtleties that are not an issue for shorter (40ft and under) fences.

For companies that have put up small fences, but wish to upscale, unexpected issues include flexibility related problems that can fatigue-fail poles and fabric and fittings. WSS experience includes a thorough understanding of load issues such as side loads from unbalanced loading. (Consider the situation when a wind gust hits one side of a pole but not the other). This problem does not usually show up in short windbreaks as the poles are reasonably stiff in both directions.

4.       Minimal interruptions with installation over and around equipment.

Fences are often positioned in areas with tight access across roadways and conveyors. The WSS installation can proceed without shutting down the roadway or the conveyor as the system includes a method of sliding the fabric along the cables. This also provides an opportunity for creating doorways and access panels.

5.       Reliability through development and testing:

WSS Senior Engineer Mike Robinson has lectured at Professional Engineering conferences in USA, Australia and New Zealand on windbreak design. At one time he worked as a research engineer for the New Zealand government. That work included inspections of failed wind fences and led to the observation that most wind fences fail because of a myriad of small subtleties.

For example some systems rely on the fabric clamping at the poles which is a potential abrasion spot. The WSS  system is all about putting the fabric and particularly the load carrying parts of it away from abrasion points.

WSS has a wide range of fabrics that have been wind tunnel tested  (for loading) and practically tested (in sites in extremes of weather). WSS also has cable strength and fatigue testing equipment and clip testing equipment to ensure all components perform as they are designed to do. (A recent cable fitting test required 100,000 load cycles per test to identify a problem then design and test the solution.)

6.       Effectiveness

WSS can offer a complete design service.  We also can provide basic aerodynamic modelling as well as access to detailed computer modelling. Each site is unique and part of our expertise is applying successful dust control configurations from one of our sites to a different site.

Having a large range of fabrics and styles of fences and canopies available provides the flexibility needed to ensure the most effective combinations are chosen.