Earthquake damage

BNZ-aerial Kaiapoi heritage

Mainmark offers the world’s most advanced earthquake remediation, liquefaction mitigation and ground-strengthening technologies.

We help ensure homes, buildings and other structures are brought back to level and given a strong, stable base, allowing for cosmetic repairs to the damage that seismic activity has caused.

In many cases our methods to fix foundation ground also correct other problems, such as bringing cracks in walls back together and re-aligning doors, windows and skirting boards.

Mainmark has successfully resolved thousands of earthquake remediation projects internationally. We have gained a great deal of experience, most notably in New Zealand, Japan, and other earthquake-prone countries. Our Ground Improvement and Liquefaction Mitigation solution has been formally recognised as a geotechnical innovation, after nearly four years in development, and with extensive trials and testing in Christchurch Red Zone. The internationally peer reviewed report for our Resin Injection Ground Improvement Research Trials has been released and the full report is now available for review on the New Zealand Geotechnical Society website.

Mainmark use a number of innovative ground engineering solutions, including our proprietary Teretek engineered resin solution. As part of post-earthquake remediation works in both Japan and Christchurch, we have developed expertise in technologies such as JOG Computer-Controlled Grouting and Terefirm Resin Injection.

Earthquake remediation in heritage buildings

Mainmark has delivered successful results to hundreds of heritage buildings requiring earthquake remediation. Our methods are a great solution, for many reasons, not least of all as raising, re-levelling and re-supporting the building gives it a new lease of life, allowing an historical structure to stand strong into the future.

A significant benefit of Mainmark’s foundation repair methods is that they are non-invasive, meaning the already fragile heritage building will not suffer further damage during the process. As the building and its floors are brought back to level, any internal and external cracks generally close up. Most importantly, structural damage is resolved, and with a stable foundation the future of the building is sound.

Our methods are effective on buildings of any size, also delivering successful results on driveways and paths. Where necessary, we also utilise technologies that strengthen the ground, so the building is not simply brought back to level, it is given a solid base and strong future.

What sort of damage can an earthquake cause to a building or structure?

Earthquakes and seismic activity cause structures to suffer substantial damage. They sink, or partially sink, down into the ground, cracks appear in walls, doors and windows jam and cease to work properly, and the ground itself can be weakened.

The level of earthquake damage depends on many factors; the proximity of the earthquake source, the magnitude of the quake, how long it lasts, the type and quality of the engineering of the structure, as well as the type and condition of the ground the structure sits on and the degree of liquefaction that has occurred. Generally, the bigger, closer and shallower the earthquake, the stronger the shaking will be, and the more damage is likely to occur.

Sinking (subsidence) can be at varying levels at various points, or the collapse can be spread across the entire footprint of a structure’s foundation, depending on where the affected ground is and how large an area it is. This can be very serious, with the structural integrity of the building comprised, it will generally become unsafe. If left untended, damage is likely to worsen, creating further building subsidence and other consequent damage.

Ground is often weakened, with liquefaction resulting in uneven ground density. Liquefaction occurs when ground shaking loosens water-logged sediments, effectively squeezing liquid up from the ground, ultimately altering ground conditions. When ground has been affected, building subsidence is common. Foundations or footings are no longer ably supported, sinking due to the weak ground.

Strengthening weak areas means unstable ground can again be suitable for the weight of a structure, without worry of continued subsidence.

What are the solutions to make a building or structure useable and safe again?


The degree of earthquake damage is unique to each project. Traditional level correction methods, known as underpinning, involve excavating or digging up parts of the foundation, pouring in concrete, waiting for it to set, and then jacking up the building off the concrete blocks. These methods often cause further substantial damage and do not strengthen weak ground. These methods can be time consuming (often requiring weeks or months) and messy.

Our methods are much friendlier, both to the building and to those that occupy it. Mainmark specialises in level correction that not only brings a building back to level but also strengthens any weak ground under and around the perimeter of the foundations, ensuring a stable base and avoiding recurring sinking issues.

Our non-invasive techniques are cost and time efficient. We re-level the building and can compact and strengthen foundation ground, delivering a stable base for the future of the structure. We have cutting edge solutions for structures of all kinds and any size, from small homes to large commercial buildings, and above ground structures to underground systems. Our worldwide proven systems provide solutions to any sector; residential, commercial, industrial, infrastructure, mining, and resources.

Various product warranties and Building Code requirements apply (please contact us to see which apply in your region or country).

Key benefits of Mainmark’s earthquake remediation methods include:

Floors and buildings are brought back to level

Non-invasive techniques keep further damage to the building, and the landscaping around it, to an absolute minimum

We don’t tear up floors and excavate ground, so historical integrity remains unaffected

Internal and external wall cracks generally close up, leaving only cosmetic treatment (plastering, painting and re-pointing brickwork)

Jammed doors and window can usually operate properly again

Gaps between floors and skirting boards general close up

Methods are effective on various foundations, such as, bluestone, brick and sandstone

The methods we use strengthen weak ground, so the building becomes level and more stable.

Mainmark methods used for earthquake remediation on heritage buildings: