Saudi Arabia, home to the vast Rub’ al Khali or Empty Quarter, has one of the world’s largest concentrations of desert sand. Yet the country imports certain types of construction sand from countries including Australia. The reason lies not in the quantity of sand available, but in the shape, size and properties of the grains.
The Empty Quarter covers roughly 650,000 square kilometres across the southern Arabian Peninsula. Its dunes contain enormous quantities of sand, with some rising more than 250 metres. However, much of this wind shaped sand is unsuitable for conventional structural concrete.
Why desert sand is unsuitable for concrete
Concrete requires aggregate with grains that can effectively interlock. River sand and crushed quarry material generally contain angular and rough particles that grip one another and allow cement paste to bind the mixture.
Desert sand, by contrast, is repeatedly transported and polished by wind over thousands of years. This process gradually rounds the grains, making them smoother and less effective at interlocking. The grains can behave more like tiny ball bearings inside a concrete mixture, reducing the material’s ability to achieve the required strength.
Another problem is grain size uniformity. Wind tends to sort desert sand into relatively similar sized particles. Good concrete mixtures require a range of particle sizes so that smaller grains can fill the spaces between larger ones. Highly uniform desert sand can therefore leave more voids in the mixture.
Saudi Arabia still imports specific sand grades
Trade data cited in the report show that Saudi Arabia imported around $138,600 worth of construction sand from Australia in 2023. Overall imports of natural sands were estimated at roughly $1.22 million that year.
However, Saudi Arabia is not simply dependent on foreign sand. The country also exported around $43 million worth of natural sands in 2023, particularly silica and quartz sands used for specialised industrial applications.
This highlights an important distinction: the issue is not whether Saudi Arabia has sand, but whether it has the particular type and quality needed for a specific construction purpose.
A growing global sand problem
The Saudi example reflects a much wider global challenge. Sand and gravel are among the most heavily extracted natural resources on Earth, with humans using an estimated 50 billion tonnes annually.
Large scale extraction of river and coastal sand can damage ecosystems, accelerate erosion, destabilise riverbanks and contribute to saltwater intrusion in vulnerable areas.
Researchers have warned that demand for construction sand is likely to continue increasing as urbanisation and infrastructure development expand, particularly in developing regions.
Searching for alternatives
Engineers and researchers are exploring ways to reduce dependence on naturally occurring construction sand. Manufactured sand produced by crushing rocks can provide more angular particles, while recycled concrete can also be processed and reused as aggregate.
Scientists are also experimenting with ways to turn desert sand into useful building materials. One approach involves combining desert sand with wood derived lignin and applying heat and pressure to bind the grains. Such experimental materials could potentially be used for applications such as paving, although they are not currently a replacement for structural concrete.
The lesson from Saudi Arabia is therefore more complex than the popular claim that the country “imports sand despite having deserts”. The real issue is that different geological processes produce different types of sand.
Wind creates vast smooth and uniform desert dunes, while rivers and crushed rock produce rougher and more angular material that is often better suited to construction.
As Saudi Arabia continues its massive infrastructure and urban development push, finding ways to use alternative aggregates and reduce demand for naturally sourced construction sand could become increasingly important.