Independent Trials Prove Engineered Sand is a Viable Solution to New Zealand's Construction Sand Shortage

Kayasand News: 14 March 2024

Independent Trials Prove Engineered Sand is a Viable Solution to New Zealand's Construction Sand Shortage

Kayasand Limited, a supplier of sand engineering equipment and technology to quarries, has successfully demonstrated an environmentally friendly and sustainable solution to New Zealand's shortage of concrete sand for construction.

Independent trials conducted by respected concrete engineer James Mackechnie have shown that sand engineered using Kayasand’s V7 technology produces consistently stronger concrete than natural sand and reduces cement content by at least 10%. This not only makes it a viable replacement for natural sand in concrete, but it also significantly contributes to the industry hitting their carbon emissions target by 2050.

The sand used in Mackechnie’s trials was produced from Greywacke rock using Kayasand’s V7-40 engineering plant at the Ward Quarry in Te Kauwhata. The plant processes aggregate and crusher dust, a byproduct of quarrying, into high-quality sand specifically designed for concrete.

“The engineered sand performed incredibly well when used in concrete,” says Bram Smith, General Manager of Kayasand. “Even when 100% of the natural sand was replaced, the resulting concrete was stronger than the natural sand control and with at least 10% less cement. Its workability, pumpability, and finish was unaffected.”

Unlike manufactured sand, engineered sand doesn’t need blending with natural sand to perform well in concrete. It is specifically designed for this purpose. It has the right shape, is graded precisely, is very consistent in quality and free of contaminants like clays and silts.

Kayasand’s unique air-filtering process also cleans the sand without water, making engineered sand a more environmentally friendly product than typical manufactured sand. It conserves another natural resource, water, and eliminates the need for quarries to manage tailings and clean up sediment ponds.

Natural sand currently consumed by the Auckland construction market is at least 720,000 tonnes per annum, with a significant amount sourced from coastal waters. It is a diminishing supply, and the industry is looking for alternatives to fill the shortfall.

A single Kayasand V7-40 plant is capable of producing 100,000 tonnes per annum of engineered sand. The larger V7 plants produce up to 600,000 tonnes per annum or more, providing a viable alternative to natural sand that meets the demand for construction sand in New Zealand.

The minimum 10% reduction of cement in concrete means a single Kayasand plant has the potential to reduce carbon emissions in New Zealand by 6,000 tonnes per year.

“There are over 300 plants using the same technology worldwide producing engineered sand. This is proven technology that New Zealand is yet to adopt.”

Kayasand's plants are designed to be economically and environmentally sustainable. They operate autonomously, are dust-free, low noise, water smart and space conscious. Kayasand's technology offers a game-changing solution to New Zealand's sand supply challenges. By utilising crusher dust from quarrying and even recycled glass and concrete, they are creating a sustainable product, conserving natural resources, reducing carbon emissions, and protecting the environment. The Kayasand engineered sand plant will officially open on 10 April 2024. Interested quarry owners and concrete manufacturers are invited to run their aggregate through the plant and perform their own tests.

Media contact:
Libby May 021 378 232