Surfside condo collapse: climate change demands adaptation in design and approach
The IDF assisted in the aid mission in the aftermath of the Surfside condominium building collapse. |
Contents |
[edit] Introduction
The Champlain Towers South (CTS) tragedy in June 2021 calls for a geotechnical and structural rethink to accommodate climate change and its effects. Designing structures to be monitored is one possible solution.
[edit] Building integrity and climate change
While the exact cause of the collapse of the Champlain Towers South (CTS) condominium in Surfside, Florida, on 24 June 2021 remains to be determined, several emerging theories point to a deterioration of the ground and the structure’s foundations due to the detrimental effects of climate change.
It's well known that the global climate is changing. Across the UK, we've experienced higher average temperatures (above the pre-industrial baseline), an increase in extreme temperature events (hot and cold), increased rainfall duration and intensity, flooding and sea level rise. Similar phenomena are being experienced throughout the inhabited world.
Specifically for the case of the Florida coastline, sea level rise has been identified as a possible cause for degradation of the CTS’s foundations.
Sea level rise results in a saline permeation of the groundwater. However, the foundations can be exposed to additional infiltrating salts through spray, borne by storm winds and flooding - routes which may have been exacerbated by poor structural design.
[edit] How rising sea levels and saltwater damage structures
Deterioration of reinforced concrete elements under saltwater attack is well documented. The invading solution, carrying chlorine ions, is able to penetrate the concrete either through the concrete’s natural porous network or through pre-existing cracks.
Over time, the chlorine ions depassivate the reinforcement environment by reducing the pH below the point at which iron oxide can form (a mechanism which, we should note, can occur whether or not the concrete is submerged). As iron oxide has a larger specific volume than steel, the reinforced zone expands, causing cracking or spalling and creating preferential seepage pathways for the seawater, creating a vicious circle of degradation.
We mustn’t forget the ground when considering climate change degradation. Higher water tables will change ground stresses, and it is also well known that salts affect clay soils electrochemically: for example, sodium ions cause clay platelets to disperse, increasing the plasticity index and, perhaps, shear strengths, depending on the parent clay mineral types and contents.
For the Surfside coastline, which comprises shallow limestone geology, another concern is karsting (where sinkholes and caves form under topography formed of soluble rocks like limestone). Although no evidence has been presented for voiding underneath the structure, an extensive ground investigation would be needed to determine whether or not it might exist.
[edit] Striking a balance between safety and reducing carbon
Although the race is now on to limit the increase in global average temperatures to 1.5°C, no such targets are in place for extreme events. Critically, climate models demonstrate that the effects of these extremes will echo throughout this century, regardless of whether or not we meet 2030 and 2050 carbon reduction targets.
For engineers, this means that structures will have to resist greater loads, with greater uncertainty, than they have ever had to resist in the past.
Traditionally, uncertainty in geotechnical design is accommodated by large factors of safety. However, this creates an interesting dichotomy.
On the one hand, we may improve safety by enlarging structural components or by reducing our estimates of ground strengths. On the other, we are striving to reduce the amount of raw materials we use in our structures, particularly focusing on concrete, to reduce the structure’s carbon cost.
Clearly, we cannot easily achieve both our aim to reduce the environmental impact of construction while upholding our duty of care to the profession, the planet and clients.
[edit] Using technology to monitor structural safety
Given the rapid pace of climate change and the prevalence of extreme events, we are now in the position of not, with a comfortable degree of certainty, being able to predict a building’s performance from historic data.
However, as our global climates worsen, computing technology continues to become more powerful. A possible solution to maintaining safety without specifying monstrous dimensions may therefore lie in the burgeoning discipline of structural health monitoring.
Low-cost sensors, placed throughout a structure, can monitor the condition of embedded reinforcement, accelerations within the structure (e.g. under wind loads) and the formation and propagation of cracks, amongst many other indicators of damage.
Timely intervention, targeting the worst-affected areas, may provide the Holy Grail of a cost effective, safe solution for construction without needing to abandon coastal areas.
However, our approach to building design must adapt, just as the structure’s design must be adapted to suit its new climatic loads. Structures must be designed to be monitored, e.g. providing inspection and repair access to key elements, and a culture of maintenance must be created.
If done correctly, maintenance could create employment while reducing the need to demolish structures and, in the event of the CTS, prevent untimely tragedies.
This article originally appeared on the Civil Engineer Blog portion of the ICE website. It was written by Christopher Beckett, lecturer in geotechnical engineering, University of Edinburgh and published on 4 August 2021.
--The Institution of Civil Engineers
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Mixed reactions to apprenticeship and skills reform 2025
A 'welcome shift' for some and a 'backwards step' for others.
Licensing construction in the UK
As the latest report and proposal to licence builders reaches Parliament.
Building Safety Alliance golden thread guidance
Extensive excel checklist of information with guidance document freely accessible.
Fair Payment Code and other payment initiatives
For fair and late payments, need to work together to add value.
Pre-planning delivery programmes and delay penalties
Proposed for housebuilders in government reform: Speeding Up Build Out.
High street health: converting a building for healthcare uses
The benefits of health centres acting as new anchor sites in the high street.
The Remarkable Pinwill Sisters: from ‘lady woodcarvers’ to professionals. Book review.
Skills gap and investment returns on apprenticeships
ECA welcomes new reports from JTL Training and The Electrotechnical Skills Partnership.
Committee report criticises UK retrofit schemes
CIOB responds to UK’s Energy Security and Net Zero Committee report.
Design and construction industry podcasts
Professional development, practice, the pandemic, platforms and podcasts. Have we missed anything?
C20 Society; Buildings at Risk List 2025
10 more buildings published with updates on the past decade of buildings featured.
Boiler Upgrade Scheme and certifications consultation
Summary of government consultation, closing 11 June 2025.
Deputy editor of AT, Tim Fraser, discusses the newly formed society with its current chair, Chris Halligan MCIAT.
Barratt Lo-E passivhaus standard homes planned enmasse
With an initial 728 Lo-E homes across two sites and many more planned for the future.
Government urged to uphold Warm Homes commitment
ECA and industry bodies write to Government concerning its 13.2 billion Warm Homes manifesto commitment.
From project managers to rising stars, sustainability pioneers and more.
Places of Worship in Britain and Ireland, 1929-1990. Book review.