SSI Schaefer rebuilds Christchurch

SSI Schaefer rebuilds warehouses in Christchurch following the devastating earthquake in 2010 and is determines to re-educate local businesses on inadequate racking and warehouse designs.

SSI Schaefer has been working closely with industry in Christchurch to rebuild warehouses following the devastating earthquake in 2010.

Joined by local partner Crown Equipment, the SSI Schaefer team is determined to re-educate businesses in the region about the severe risk caused by inadequate racking and warehouse designs in the aftermath of earthquakes.

It is difficult to imagine that over 8,000 aftershocks have taken place at the Canterbury region since the 7.1 earthquake on September 4th 2010.

When you visit the region and see the shell of a local church or the cantilevered home of a resident hanging over the side of collapsed cliff face twelve months later, it certainly hits home that the rebuild is a slow and arduous process.

Unfortunately aftershocks cannot be predicted and are expected to continue for another year, if not longer in the region.

Some of these aftershocks relate to the 7.1 September 2010 earthquake and others to the 6.3 February 2011 earthquake.

Aftershocks are unpredictable and dangerous, can be of larger magnitude and buildings already weakened by both of the Christchurch earthquakes are now susceptible to further damage.

A significant amount of forethought must be incorporated into the way buildings are repaired or rebuilt and the warehouses and distribution centres need to be designed to withstand large earthquakes and also sustain aftershock damage.

After the Canterbury Earthquake, SSI Schaefer invested a significant amount of resources and teams to assist with the initial re-build of dozens of warehouses in the region and to install new racking that would adhere to New Zealand building codes.

SSI Schaefer's buildings withstood earthquakes and aftershocks

Much of the competitor racking Schaefer removed from warehouses in the region after the first earthquake clearly did not meet building guidelines for the country.
Further inspection after the February 11 earthquake indicated that all of the SSI Schaefer re-builds had withstood the second quake and all further aftershocks.

Additional inspections undertaken on SSI Schaefer earthquake-designed cold stores in the region built before the Canterbury Earthquake showed they are all still fully-operational after two earthquakes.

This is a true reflection on how adequate earthquake-designed racking and storage should withstand even the worst of natural disasters.

SSI Schaefer has global experience in earthquake re-builds and has worked in hotbed areas such as the Philippines, Indonesia and San Francisco.

How did SSI Schaefer racking withstand an earthquake?

The answer is simple. SSI Schaefer racking is designed to consider the regional environment where the equipment will be installed and is a system of racking instead of components.
New Zealand is classified under either Zone 2 or 4 based on the historical number of past earthquakes. SSI Schaefer strictly adhere to, and base all racking design for New Zealand around FEM 10.02.02 and NZS 1170.5 - 2004 (seismic code) and or Uniform Building Code 1997 edition – Vol.2 Division IV ‘Earthquake Design’.

Based on the New Zealand codes SSI Schaefer takes into consideration:

• The pallet load and seismic action are applied on cross aisle and down  aisle direction.
• The action forces are based on the New Zealand standards.
• The frame profile and bracing requirements are determined by forces acting on cross aisle direction.
• The beam profile and spine/plan bracing is determined by forces acting on down aisle direction and rack configuration used.
• Ductility.
• The rigidity and strength of the racking system is determined by the profiles properties, material properties, the connection strength and stiffness.

The materials they are using to manufacture all components are controlled and higher than the international standards. For example the post is made from SS490 (as JIS) with minimum yield strength of 390N/mm^2.

The requirement of JIS is 285N/mm^2.  All SSI Schaefer materials are purchased directly from Steel mills and will verify the requirement base on a Mill certificate and independent tensile test report.
    
The racking is checked in the static calculation as below:

1. Base plate size and thickness as per requirement (vertical force and shear force).
2. Floor fixing as per requirement (vertical force and shear force).
3. Post profile selection based on compression force and bending.
4. Frame bracing check based on tension capacity and bearing.
5. Beam design.
6. Spine and plan bracing component checking.
7. Point load acting on floor by racking post and spine bracing.  
8. In addition, SSI Schaefer column tests are extremely rigid and follow stricter guidelines than other racking.

The column test sample is equipped with a load cell and linked to a measurement device to monitor the behavior of the column in the load test.

The accurate and precise measurement of the test ensures that the team has a greater understanding of the exact behaviour of the post and guarantees a quality system for the customer.

SSI Schaefer will continue to assist Christchurch companies to not only re-build their warehouses, but will also try to educate the region on the importance of following the racking guidelines of the New Zealand Building Code.

Is your warehouse or building in an earthquake zone?

If your warehouse has received damage from the earthquakes and you have not had your racking tested then do so immediately.
You may have structural damage to the racking foundations and not even realise it.

One more aftershock could potentially cause problems for your racking and may risk the safety of your workers.

Stop and assess your current racking; does it adhere to the New Zealand Building Code? Can it withstand earthquakes?

Aftershocks can occur for up to twelve months after an earthquake, why risk the safety of your workers when a simple test can be carried out on your existing racking which can assess any structural damage that may have occurred since September 2010.  

Alan Clark

Managing Director SSI Schaefer Australia

http://www.ssi-schaefer.com.au/