Lightweight fill

Lightweight fill for civil engineering by Weber

Geotechnical application with Arlita Leca

What is maxit LWA?

maxit LWA was initially developed to provide insulation to roads, railways and ditches across Scandinavia. It is a lightweight expanded clay, formed by heating and firing natural marine clay.

The process transforms the clay into various sized lightweight ceramic granules, which have a hard ceramic shell and a porous core. In this form, the material has excellent insulating properties and is extremely lightweight with a bulk density of between 0.28 to 0.33 tonnes per cubic metre. These granules are also fire resistant, frost resistant and chemically inert with no hazardous properties.

Advantages of maxit LWA:

• Eliminates costly settlement periods
• Reduces weight on underground voids
• Has superb insulating properties
• Eliminates or reduces expensive load transfer techniques
• Is free draining
• Allows reduced bulk of retaining structures
• Is installed using the same machinery as conventional fills
• 1m compaction layers vs 0.25m with traditional fills
• Not susceptible to oil/diesel spillages
• Surplus can easily be reclaimed and re-used

These properties makes maxit LWA your best choice for a wide variety of civil engineering applications and especially concentrated solar power units!

maxit Arlita Leca for your Concentrated Solar Power Units

Because of the properties of Arlita Leca - see below for more specific details and technical information about maxit LWA - lightweight expanded clay aggregate engineered by Weber is designed for your CSP projects: parabolic dishes, Sterling dishes, Power tower...

The versatile solution for so many civil engineering applications

Practical advantages of maxit LWA:

• Not damaged by repeated freezing and thawing or by ageing
• Thinner layers required for frost protection
• Reduced digging depths means lower volumes of material for relocation
• Reduced requirements for imported material
• Reduced transportation
• Reduced residential upheaval
• Less disturbance to substrata
• Allows lower structure heights

The sheer breadth of its application and the benefits it can offer as a free draining, lightweight fill have now become recognised by civil engineering practices for highways, rail and marine applications, with a departure document to the Specification for Highway works for both Structural and General Fill now in place and a number of successful Highways agency and Network Rail projects completed throughout the UK.

Transport and placement

Its light weight makes maxit LWA more economical to transport, typically needing a fifth of the number of loads required by traditional heavyweight materials, and this also has obvious environmental benefits.
Cost benefits of maxit LWA:

• Reduced transport costs
• Reduced sitework costs
• Reduced structural costs
• Reduced timescales

Reducing settlement

On soft soils and subgrades

maxit LWA's ability to reduce settlement can offer massive benefits, reducing timescales from years to a few months for new or extended carriageways or for embankments and even, in some instances, eliminate settlement periods altogether.

1. Using maxit LWA on large scale cut and fill operations and construction on soft soils and bad ground, can overcome stability problems, reducing the risk of landslide and deformation.
2. Used in road embankments, maxit LWA exerts much lower horizontal earth pressures compared with other backfill materials, helps improve stability and reduce the need for counterfill.

During carriageway widening

When newly constructed fills are laid next to existing fill such as a carriageway widening or additional rail line, settlement of the new sub-grade fill often leaves the new surface lower than the original existing surface and could pull the existing surface out of level.

1. The lightweight aggregate is installed in layers adjacent to the existing carriageway and compacted.
2. Each layer of LWA is encapsulated by Geotextile to retain and stabilise the material whilst the new road pavement is constructed above and the existing pavement excavated
3. The renewed embankment is filled with maxit LWA adjacent to the new carriageway and compacted.
4. The new lightweight, insulated carriageway is completed and ready for traffic.

5. A road or rail bed widened with maxit LWA is less prone to level differences caused by settlement.
6. Excavation and backfill with maxit LWA helps stabilise the bank.

Reducing pressure on retaining structures

When used against retaining walls, maxit LWA will reduce the weight acting on the rear of the structure by at least 75%, in comparison to traditional fill materials.

1. maxit LWA backfilled against bridge abutments reduces loading on the underlying subgrade, exerts less pressure on adjacent pile foundations and prevents settlement irregularities.
2. Backfilled against a retaining or basement wall, maxit LWA settles less and exerts 75% less horizontal earth pressure than conventional fill materials.

Reducing earth pressure

In areas prone to mining subsidence or where ground conditions contain natural subformation voids, drainage, culvert or tunnels and there is a danger of collapse, expensive techniques such as load transfer are often considered. However, using maxit LWA can eliminate these costs and considerably lighten the load to provide similar benefits to those when used in weak soil areas.

Increasing slope stability. maxit LWA will also reduce the risk of bearing capacity failure and increase the stability of the side slopes.

maxit LWA will also provide an efficient drainage for your constructions.

1. Used in place of general fill, maxit LWA can be used to strengthen the slope face of an embankment.
2. Excellent insulating properties make LWA the ideal filling for road and railway embankments where frost stability requirements determine sub-base thickness.
3. In sloping terrain, cuttings and ground which has high groundwater levels, LWA drainage trenches and drainage layers can be used to dry out road and rail structures and keep them free draining to prevent pore water pressure build up, slope erosion and provide slope stability.

Contact Weber maxit

geotech.maxit-cms.com - maxit Weber website

You can download our documentation (and technical information) here.