Cyclonic Tie-down Blocks For Site Preparedness During The Cyclone Season
No country is safe from the dreadful consequences of natural disasters. Australia has its own issues; the varying climate and geography make it prone to hazards such as heatwaves, cyclones, bushfires, floods, landslides, earthquakes and tsunamis. These make billions of dollars of impact on the Australian economy every year, bringing about loss or damage to people and wildlife as well.
A special report released by Deloitte Access Economics and commissioned by the Australian Business Roundtable for Disaster Resilience & Safer Communities in October 2021 suggests that natural disasters cost an average of $38 billion per year to the Australian economy. The annual cost is estimated to increase to $73 billion by 2060, even under low emissions scenarios.
Natural disasters are inevitable. They have been occurring for centuries and will continue to do so. With increasing global warming and climate change, disasters are more intense and frequent. Unfortunately, there’s very less we can do to prevent them altogether. However, there are ways to minimise the destruction they cause.
Tropical Cyclones in Australia
Tropical cyclones alone are responsible for devastating damage to infrastructure, industries, forests and ecosystems in cyclone-prone regions in Australia. The cyclone season in Australia begins in July and lasts throughout the year, hitting the Australian coastline every November up until April.
These non-frontal, low-pressure systems originate over the warm and still sea surfaces when the water temperature exceeds 26.5°C. Due to low atmospheric pressure, the warm water rises rapidly, creating a gap filled by the surrounding air. The filling air travels long distances from all directions at incredible speeds resulting in a spiral instead of filling the gap. More air coming to fill the gap joins the spiral as it can’t pass directly through it. The tropical cyclones created in this way can rise up to 10 km in height and last from 3 to 7 days, moving over the ocean’s surface.
Cyclones naturally fade away or die as they cross a cold water surface or a land surface. The tropical cyclones hit the land surface on the northern coastline of Australia. The northwest Australian coastline from Exmouth to Broome and the northeast Australian coastline from Port Douglas to Maryborough is exposed to the most hazardous tropical cyclones making Western Australia and Queensland highly vulnerable to its terrifying consequences.
When a tropical disturbance reaches a wind speed greater than 65 km/h and lasts for 10 minutes, it’s classified as a tropical cyclone. Similarly, when the 10 minutes of the sustained wind exceeds the speed of 120 km/hr, it’s classified as a severe tropical cyclone. A tropical cyclone is further categorised into five categories, as expressed below.
|1||34–47 knots; 63–88 km/h||49–67 knots; 91–125 km/h||Minimal|
|2||48–63 knots; 89–117 km/h||68–89 knots; 126–166 km/h||Moderate|
|3||64–85 knots; 118–157 km/h||90–121 knots; 167–225 km/h||Extensive|
|4||86–107 knots; 158–198 km/h||122–151 knots; 226–280 km/h||Extreme|
|5||>107 knots; >198 km/h||>151 knots; >280 km/h||Catastrophic|
Effects of Severe Tropical Cyclones in Australia
Category 4 and 5 are the most devastating cyclones. These cyclones cause extreme winds, heavy rain and storm surges, affecting lives and infrastructures in coastal areas and beyond. Mining sites are usually resilient operations, but even they aren’t resistant to the adverse effects of cyclones.
Strong wind during a severe tropical cyclone creates wind-borne debris that can harm people and cause extensive property damage like disorientation of buildings and structural entities in residential areas, industries, construction and mining sites.
Heavy rainfall caused by tropical cyclones results in flash and widespread flooding, damaging properties, roads, bridges and other infrastructures.
The combined damage from strong winds and heavy rainfall can affect the communities and industries for months. Damages include blown away roofs, verandas, garage doors, broken doors and windows by fallen tree branches, other wind-borne debris, etc.
When a cyclone approaches, there’s a rise in sea level above the normal tide levels due to strong onshore winds, referred to as a storm surge. It’s more dangerous than strong winds and can cause severe injury and property damage, like destroyed buildings and washed away roads. The seawater flooding caused by storm surges can last for several hours and extend up to 100 kilometres along the coastline and several kilometres inland in low lying areas.
Storm tides can be far more damaging than storm surges. When a cyclone’s water surge coincides with high tide, it results in storm tide. A 3-metre storm surge on top of a 2-metre high tide produces a storm tide that is 5 metres above sea level.
How to Prepare for the Cyclone Season
Nothing can be done to reverse the terrible effects of tropical cyclones after they occur. Unfortunately, even the authorities seem to be more invested in post-disaster relief than taking precautions.
2017 data shows that 97% of disaster funding goes to post-disaster relief and recovery, and only 3% is spent on mitigating a disaster beforehand. However, there are certain measures we can undertake to prepare ourselves and our properties before the cyclone season begins to minimise the possible damage.
Here’s a list of things to run down for a thorough inspection of your property before the cyclone season.
- Check metal components for corrosion.
- Fix roof claddings, battens, trusses, bolts and screws to secure the roof.
- Check for rot, termites and loose fittings in timber and replace or fix them.
- Replace worn-out window and door seals. Make sure the glasses on windows are of correct wind classification based on Australian standards.
- Install wind and debris rated garage doors or invest in a temporary bracing system to support the doors.
- Clean gutters and downpipes regularly to prevent them from blocking.
- Check the condition of other components attached to the building like porches, verandas and patios.
- Properly manage other items around the property like fences, sheds, boats, caravans, and trees.
- Choose a safe space inside the property with solid walls and doors. Supply the room with necessary goods so that you can survive in that room during the occurrence of a cyclone.
Preparing a Mining and Petroleum Site For the Cyclone Season
Mining and petroleum industries are at high risk during the cyclone season. When faced with natural disasters, businesses must consider using engineering to effectively minimise loss and business interruption.
With the right site-specific plan in place with a year-round approach, businesses can secure their assets from being affected by tropical cyclones or other disasters. It’s also critical to have full support from the management and employees to execute the plan successfully. The employees must understand the plan and the reasoning behind it.
Focusing on the adverse effects on mining industries during the cyclone season in Western Australia, the WA Department of Mines, Industry Regulation and Safety (DMIRS) has outlined cyclone safety precautions emphasising adequate plans and training to be undertaken by the employers to protect the employees.
It’s likely for cyclones to isolate workers from emergency services, infrastructure, transport and communications. To minimise the hazards faced by workers, DMIRS encourages the mine owners to focus on the following aspects.
- Coordination with the Department of Fire and Emergency Services (DFES) and local authorities to develop emergency procedures in the work site
- Regular planning, training and review
- Undertaking detailed site-safe actions under each level of Cyclone Warning Phases, i.e. Blue, Yellow and Red
- Securing transportable buildings like accommodation units and offices on cyclone sensitive work sites
- Safe evacuation plan of non-essential personnel before the condition worsens (during Blue or Yellow Warning Phases)
- Moving all personnel on the site to a designated shelter prior to the cyclone’s arrival
- Availability of essential supplies like food, water, and medicine to all isolated workers
- Reliable emergency communication backup to contact external emergency services during Red Alert Phase.
- Availability of battery-powered radios on-site in the event of a power outage to get information about the cyclone.
You can check out the DMIRS site for details.
Site Preparation with Cyclonic Tie Down Blocks
During the cyclone, objects such as storage containers, vehicles, offices, transportable houses, etc., are at high risk of overturning or blowing away. This can damage properties and work sites or even harm people. Securing these to the ground helps them withstand cyclone pressures and prevents them from being loose.
Withstanding sudden changes in cyclonic pressure is no joke. Equipment and other objects used in mining are already heavy, but category 4 and 5 cyclones can easily turn them upside down or sweep them off with heavy flooding. It would help if you had extreme strength to stand tall against the devastating force of a cyclone. Cyclonic tie-down blocks are here for just that.
Concrete tie-down blocks are heavily reinforced blocks designed and engineered to hold objects down to earth stably. They secure things like containers, equipment, vehicles and even buildings, no matter how heavy they are. The colossal density of these concrete blocks withstands harsh winds, sudden flooding and other extreme weather conditions during the cyclone season.
Cyclonic tie-down blocks come in different sizes, so you can choose according to your requirements. Due to a wide range of size options, you may be confused about which one to get. The right size selection comes down to your object’s weight to be secured and the severity of the cyclones in your area. It’s best to have a professional examine your site before purchasing these tie-down blocks.
How to Install Cyclonic Tie Down Blocks
Cyclonic tie-down blocks are super easy to install. First of all, they stand unassisted on the ground surface, which saves you from the hassle of penetrating the earth to fasten anchors.
Secondly, most concrete blocks come with swiftlifters/fork pockets cast in, making placement extremely easy. Usually, an equal number of concrete tie-down blocks are placed on both sides of the object you would like to secure and tied together over the objects with metal chains or heavy-duty ropes.
For more information on correctly using tie-down blocks in cyclonic areas, you can check out the correct way to tie down a sea container in cyclonic areas.
DALLCON is the leading brand of precast concrete products in Australia. Our cyclonic tie down blocks are neatly-finished, durable, affordable, and easy to install. They are engineer-approved to be used in the mining or construction industry, even in the most cyclone-prone northern parts of Western Australia.
With these concrete cyclone tie-down blocks, you can save your valuable assets from being blown or swept away during the cyclone season. Call 1300 325 526 or contact us to discuss your requirements in detail with one of our specialists. Let us take care of your cyclone protection needs, from selection all the way to delivery as well as installation.