Designing Resilient Foundations: The Importance of Stiffened Grid Type Beam and Slab Foundation

When designing foundations for homes, it's essential to consider the potential for lateral spreading or stretch at the surface, particularly in areas prone to seismic events. One effective solution is to implement a stiffened grid type beam and slab foundation system.

This approach involves tying together foundation solutions to improve resistance to lateral stretch and ground deformation. This is crucial for reducing inertial loading on foundations and minimizing settlement potential during future earthquakes. By using light-weight materials for roof and wall claddings, you can further enhance the resilience of your foundation design.

In New Zealand, designing foundations in adverse ground conditions requires careful consideration of seismic events. The MBIE Guidance provides valuable information on designing resilient foundations, including the use of stiffened grid type beam and slab foundation systems. However, it's essential to note that these solutions are based on the concept of 'readily repairable' and may not conform to the 'no repair required' criteria for High Performance Homes.

If you're planning to install in-slab heating, it's crucial to ensure that the heating pipe is installed either on the polystyrene or fixed to the reinforcing mesh. This will help prevent potential issues with differential movement and settlement.

The primary difference between foundations designed for minimum standard homes and those designed to the Healthy Homes Design Guide requirements is the requirement for insulation in the latter. All foundation solutions outlined in NZS3604:2011 are suitable, provided they meet the necessary design criteria.

In conclusion, designing resilient foundations requires careful consideration of seismic events and adverse ground conditions. The use of stiffened grid type beam and slab foundation systems can significantly improve resistance to lateral stretch and ground deformation, reducing the potential for settlement during future earthquakes. By incorporating light-weight materials and in-slab heating solutions, you can create a robust and resilient foundation system that meets the demands of modern building design.

References:

* Conference on Soil Mechanics and Foundation Engineering (Mexico City)

* Institution of Eng., Australia and the Department of Adult Education, University of Adelaide

* NZS3604:2011 - New Zealand Standard for Residential Buildings

* MBIE Guidance - Repairing and Rebuilding Houses Affected by the Canterbury Earthquakes

Stiffened grid type beam and slab foundation