Product Design and Application

Retaining Wall & Archway Blocks

Standard Blocks

The standard blocks come in half block, full block, extended block and various end block configurations. The tapered rectangular shape of the voids ensures maximum strength by placing rebar far from the neutral axis. Blocks have vertical slots on the outer edges that allow quick forming to close gaps when blocks are placed with gaps to produce nonstandard configurations.

Base Blocks

When required, RASBlox has a set of base blocks with solid bottoms and increased surface area to provide additional support for varying soil conditions.

Rock Anchor Blocks

The Rock Anchor Block can be used to anchor a retaining wall to a rock face or to tie back a parallel set of walls like a railway grade separation or bridge approaches that need to be kept within a narrow right of way. This is an exploded view displaying anchor tubes. Anchor tubes can be any size and can be angled as needed to align with anchor points. They can be recessed and filled after tensioning to provide a consistent outside appearance. The anchor tubes can also be used as drains to prevent the build up of hydraulic pressure. The use of smart tech to monitor anchor performance allows for the tracking of structure performance. If there is an indication of possible anchor failure, additional anchors can be drilled through unused anchor tubes.

Anchor Bolt Blocks

The Anchor Bolt Block is designed to allow for the attaching of any type of anchor device to the inside face leaving the outer face clean for aesthetic applications. Any type of anchor device such as eye bolts, threaded rods or clevis rods can be cast into the block. The block can be anchored to a parallel retaining wall, pilings, soil anchors or deadman weights. The project engineer can provide the anchor specification required to meet the loading for each site. Because of the monolithic nature of the RASBlox system, the engineer can specify how many blocks require anchoring instead of having to anchor each retaining wall component.

Traffic Barrier/Landscape Blocks

The top of retaining wall structures can be capped in several ways. The top row void can be filled flush with concrete or a Traffic Barrier Block or a landscape block can be used as the final course of blocks. The Landscape Block is stepped, allowing the area surface to be filled flush by landscaping or paving can be placed to the top of the block. If desired, voids for fence post or guard rails can be cast into the top edge. The traffic barrier is designed to become part of the monolithic structure to provide maximum strength and durability. It also allows for incorporation of utility lines for streetlight standards and casting of standard or signpost attachments.

Archway Blocks

The arch, a compression structure, is one of the oldest and strongest structures available; some arches have been in use for over a millennium.

The design limit of compression structures is only dependent on the compressive strength of the materials used to build them, and compressive strength can be designed to suit the loading requirements of individual projects.

RASBlox archway structures have steel reinforcing, making them more resistant to seismic incidents and unintended shock loads from accidents like train derailments or shock loading from avalanche impacts.

The internal reinforcement of RASBlox tunnel structures provide an excellent choice for construction of containment corridors for dangerous goods moving through urban areas. These corridors would contain most of the energies resulting from an incident and contain spills of hazardous materials.

When used as a bridge, RASBlox Archways are resistant to flood damage because of the monolithic nature of the structure resulting from the reinforced concrete core. Part of a foundation can be washed out and the RASBlox structure will remain competent.

The RASBlox Archway System consists of a variety of blocks. End blocks are used to contain the poured concrete and provide an aesthetic outer end. Intermediate blocks make up most of the arch structure; top blocks are designed to facilitate installation of the final reinforcing cages and final concrete pours.

System Functionality

Contour Retaining Walls

Retaining walls that follow the terrain are constructible by adjusting the angle of wall sections to match the grade of the terrain, and then by joining the sections using the quick forming slots cast into each block. This produces a solid monolithic wall that can be used to follow road grades or land elevations. These joints retain the full strength produced by the internal rebar cages. Additional rebar may be placed in the joint areas if required by design and at the discretion of the project engineer.

Post Tensioning

Post tensioning can be applied after assembly to enhance strength at high load sections of the structures. Blocks anchored with rock anchors or cross ties between parallel walls overcome turnover forces.

90⁰ Junctions

The system uses a combination of three specialty blocks to construct full strength 90⁰ junctions which also allow for utilities to run through the junctions in all three directions.

Rebar Cages & Utility Run

RASBlox blocks with rebar cages and a utility run. Project engineers design the rebar cages to yield the design strength required for specific projects.

Radius Curves: Convave/Convex

Any radius curves or complex bends can be constructed with the RASBlox system. Simply leave a gap between the blocks at the back side and keep the outside edges tight together. The gap at the back can be formed by placing a piece of forming material of the correct width into the slots on the vertical edges of each block. The blocks can be kept tight together on the front by using any of a number of tensioning devices. Both concave and convex curves can be built.

Cantilevered Retaining Walls

Cantilevered retaining walls can be constructed to gain needed surface area in difficult locations. Design must ensure the base is adequately anchored and the retaining wall adequately tied back. Rock or soil anchors can be used for this application. The ability to construct straight or cantilevered retaining walls that can be securely anchored to a number of piling options on the bottom and tied back using various rock or soil anchors, make it an excellent choice for constructing roads or rail line next to lakes, rivers or beach fronts where scour is a risk.

Tipped Structures

Retaining walls can be constructed tipped backward into the fill zone to take advantage of gravity, reducing the need for tie back anchors. With the use of our patented wedge blocks, retaining structures can be tipped at any stage of construction; then, the top is brought back to horizontal by installing another wedge block. A 10° wedge is shown here, wedges can be cast to any angle required at the discretion of the project engineers.


The RASBlox system can be used to construct bridge and overpass abutments of almost any configuration. When used for bridge abutments, the resulting monolithic structure is superior to many other systems because it could remain competent with a significant portion of the base washed out by flooding. When placed deep enough it will provide excellent protection from water scour erosion. Non-symmetrical abutments are easily constructed.

Protective Structures

This is a design concept for a railway or highway avalanche protection structure as well as for safe corridors for the movement of dangerous goods through urban areas. The design allows for curved tunnels by using the slots casting method to form in the gaps used to produce the curve. The retaining wall on the end would be fully integrated into the tunnel structure, making both structures more robust.

Installation demonstration of the innovative new retaining system from RASBlox

The first time the RASBlox system was used to construct a retaining wall was in November of 2020. This wall was constructed as proof of concept and to demonstrate constructability. We were extraordinarily successful and easily met all our objectives.


  • The amount and size of reinforcing steel is determined by the loading anticipated for individual projects.
  • The use of stainless steel, galvanized or epoxy coated reinforcing steel should be considered for some applications.
  • All casting will follow recommendations in the Best Practices Manual for Precast Concrete Retaining Wall Systems published by the National Precast Concrete Association (NPCA) Second Addition, 2008.
  • Only certified lifting loops should be used.
  • The Project Engineer should ensure all Quality Control and Quality Assurance practices are followed and documented.
  • The retaining wall base may be anchored by being buried, by being set on pilings or by being bonded to a concrete footing.
  • Design and construction of structures using the RASBlox system should follow applicable standards, codes, guidelines and best practices, including but not limited to:
     • EGBC Professional Practice Guidelines: Retaining Wall Design Ver 1.1 (Feb 25, 2020).