Engineered Walls

Technical Talk about Retaining Walls

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You’ve seen this picture many times on our website and brochures.One reason is that this retaining wall and fence is aesthetically pleasing. Another is that it is an amazing engineering feat. Engineered walls, whether simple or complex, are extremely technical in nature.
Here are some of the factors we consider when bidding retaining walls:

    Lateral Earth Pressure

Lateral Pressures image

This picture is a cross section of images used to teach the principle of earth pressure to students in Civil Engineering at Purdue University. Both brick and stone retaining walls must be engineered to withstand these pressures using appropriately-dense materials , including a resilient mortar. Also included in the curriculum are the means to measure things like: (Note: This is only a partial list and was verified at Wikipedia.com).

    1. Soil Composition
    a) Mineralogy
    b) Grain Size distribution
    c) Classification of clays, silts, and porosity
    2) Sieve Analysis
    a) Water Permeability
    b) Drainage
    c) Liquid Limit
    d) Resultant pressures and directional flow
    (which is dependent upon the following):
    3) Mass to Volume Relations
    a) Specific gravity of solids
    b) Density (bulk and wet)
    c) Buoyant, Dry, and Porosity Densities
    4) Seepage measurements (via: analysis of aforementioned factors)

Referring once again to the picture of Omega Masonry’s engineered retaining wall, notice that an elevated driveway ascends to our client’s beautiful hilltop home. The incline had already been established, and the volume of earth that would press against the retaining wall was clearly defined. Our task was to engineer a wall that would sufficiently carry this load without succumbing to the pressures placed upon it.

Although this simplified illustration explains the different types of wall engineering our technicians can utilize, it does not convey the fact that most engineered walls employ a combination of approaches, in order to sufficiently accommodate the pressures it must endure.

800px-Retaining_Wall_Type_Function

    Drainage

Once again, Wikipedia sums the issues of retaining wall drainage in layman’s terms:

“At zero effective stress soil has very little strength and layers of relatively impermeable soil may heave up due to the underlying water pressures.”
The factors that determine these risks are determined by the soil’s composition, porosity, flow, and drainage. The results of this measurement determine the number of drains, (and their spacing), in any retaining wall design.


    Materials

Concrete, mortars, rebar, and stones are not created equal. That’s why Omega Masonry insists that our concrete and masonry providers produce a consistent, reliable product that we can trust to withstand the pressures placed upon engineered walls. We currently employ TXI and Southern Concrete products and seek out the highest grade rebar we can attain when building retaining wall foundations. By concerning ourselves with the quality of our masonry materials, we can ensure that every retaining wall we build will provide a lifetime of reliable service.

Whether your retaining wall project encompasses a massive hillside or a simple garden plot, the principles are the same. At Omega Masonry, our engineers help ensure that your retaining wall is something you can be proud of.