Geotechnical Services

Tennessee’s geology is one of the most varied in the nation. That means every site is different. As a result, solutions to remedy problem sites can be just as varied. Fortunately, with decades of experience in the area, Perry & Associates has seen a lot of different site issues, and a lot of different solutions. Rest assured, the field work scope and engineering solutions will be custom tailored to your specific project. We frequently integrate our pool of experienced and trusted subcontractors to get you the answers you need in order to proceed to your successful project conclusion.

Even after the final report is sent, and the invoice is paid, we still consider ourselves a part of the project team. Don’t think you lose us as a team member at the completion of our approved scope of services. We understand how important this project may be for you, and if we can be of assistance at any point in the project lifespan, we are always more than willing to help.

Subsurface Exploration Studies

This is most commonly referred to as “a geotech study”. This study utilizes excavators or geotechnical drilling rigs to explore the subsurface strata. This is valuable for determining how much load the soil can tolerate by your building or retaining wall before it settles enough to start causing cracks or rotation to your structure. This study is also very helpful in determine the depth to bedrock so you can adjust your grading plan to reduce or eliminate the amount of rock you’ll need to remove from the site.

Sinkhole Investigation/Remediation

So, think you may have a sinkhole? No problem! We can determine if it is indeed a sinkhole, or (for example) an old burn pit Ole Farmer Brown forgot to tell anyone about. Even if it is a sinkhole, it’s not the end of the world just yet. There are several state-approved methods of properly mitigating sinkholes that could possibly allow you to build on top of! If sinkholes are a concern for your project, let us see if we can help!

Slope Stability Analysis

During the 2010 Nashville flood, many landslides occurred. Now, slope stability analyses are required in several communities in and around central Tennessee before the first grading permit will be granted. Furthermore, we have clients who request this service even if not required by the city government. They understand the cost of this service is a small fraction of the cost to remediate an entire failed hillside.

USDA Soil Grouping

Many civil site clients of ours have encountered roadblocks in their design when the commonly accepted soil type isn’t exactly complimentary to their stormwater design. We can sample the soil at the exact location of their stormwater feature, run the appropriate laboratory testing, and determine exactly what USDA type soil it is! Most of the time, the results are must more favorable than what was commonly accepted! We love it when the data helps make their job easier.

Infiltration Testing

Infiltration testing is now required by many municipalities in the central Tennessee area. This service involves measuring the absorption rate of the subsurface soil at the exact location of stormwater features. Many times, the municipality asks for the infiltration results before they will even look at the proposed site plan. Like “perk” testing for single-family residential septic systems, infiltration testing is just as important for your commercial and/or multi-family stormwater management system plan. We suggest this service be one of the first services you engage us for.

Geophysical Services

Geophysical services are a great option if you’re limited to non-destructive means of exploration. These services vary in method, but in general, they provide a 2D image of the subsurface profile by using either shock waves or electrical resistance. The soil/bedrock interface is typically very pronounced. Some studies have even captured old ponds that have been filled in over time, and underground public utilities. We sometimes combine this service with sinkhole explorations, as this service can sometimes capture the bedrock void that is causing the sinkhole to occur.

Pavement Evaluation and Section Design

This service is typically used on projects where a very large paved surface is included in the purchase or sale of a property. The potential buyer understandably wants to know if he’s going to have to re-pave the entire parking lot in the next few years. We would walk the area and note any surface defects, and extent of surface pavement deformation. Sometimes we even extract representative asphalt cores to determine the existing pavement thicknesses. For fresh undeveloped sites, we take the anticipated traffic loads, the strength of the existing subgrade, and design a recommended pavement section to be considered in site design.

Geotechnical Desktop Review of Potential Sites

Interested in a site, but not ready for a full geotechnical study? Utilize our knowledge and experience of the general area to give you a good idea of what possible issues you’ll need to consider during development. We also pull information from online databases to determine geologic conditions, problem soil areas, etc, and then describe what those conditions typically mean for the developer. This is a great way to get a preliminary understanding before you proceed with the negotiation and/or purchase process.