Compaction Grouting Cost Information
<p><p><h2>Commentary</h2>Payment for compaction grouting typically consists of a drilling pay item measured by the lineal foot (LF) and a grouting pay item measured by the cubic yard (CY).
Compaction Grouting Fact Sheet
<p><p><h2><img class="aligncenter wp-image-2544 size-full" src="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/…; alt="Cartoons showing the sequence of compaction grouting under a footing." width="1151" height="371" /></h2><h2>Basic Function:</h2>Compaction grouting strengthens and stiffens soils through densification by displacement of the soil as grout is injected into the soil.&
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Compaction Grouting Specifications
Summary of Example Specifications
<p><p><h2>Summary of Example Specifications</h2><div class="grayed-title subsection"><strong>Specification Name/Number:</strong> Elias et al. (2006b) Guide Specification: Compaction Grouting</div><strong>Reference(s):<br></strong><em>Elias et al. (2006b)</em></p><p>This specification is very clear and detailed in the components that it provides. Site conditions, design criteria, and acceptance criteria should be added to this specification, and sections requiring project specific input should be tailored to the particular project. Overall, this is a good guide specification to start from, but it should not be considered entirely complete with these sections missing. Sections may be added as deemed fit, and the addition of site specific requirements would make this specification more readily useable. It provides clear and concise commentary throughout. The sections provided are easy to follow and straight forward. A sufficient amount of guidance and explanation is given in the appropriate sections.<br>The elements of risk are shared evenly between the contractor and the owner. This specification provides the information required (aside from site specific constraints which should be added as necessary per project) to bid the job fairly. Contractor qualifications are outlined clearly and are not biased or constricting. This specification does not require overly intricate or expensive components. Good QC/QA guidelines for the active constructive monitoring method are given, but again it requires the addition of several project-specific key components to be considered complete.<br><div class="grayed-title subsection"><strong>Specification Name/Number:</strong> Sample Specifications for Soil Improvement By Compaction Grouting</div><strong>Reference(s):<br></strong><em>Hayward Baker, Inc.</em></p><p>This specification from Hayward Baker is well composed and includes nearly all pertinent information for a compaction grouting specification. Some information is left as blanks to be filled in per the project requirements. This specification would require minimal modification to be sufficient for use for a project. It provides clear and concise commentary of the requirements for the project, and is ordered in a logical manner. It gives sufficient guidance for key components. The elements of risk are shared evenly between the contractor and the owner.<br>This specification provides the required information to be bid fairly and is not biased toward any particular product or contractor. It does not require overly intricate or expensive components. This specification gives good detailed guidelines for both active constructive monitoring and post-construction verification. The components considered most critical were present, and any information left out is given a blank to be filled in for a specific project.<br>Some considerations should be taken since this specification is provided by a specialty contractor. Sections may be reworded based upon the client/owner’s requirements or assumption of risk.</p></p>
Design Procedure Based on Numerical Modeling
<p><p><strong>Reference(s):<br></strong><em>Shuttle & Jefferies (2000)</em></p><p>For the design of a compaction grouting program that requires very predictable results, numerical modeling can be used to establish proper design criteria. These analyses can be performed on a large strain critical state elastic-plastic finite element program for this purpose. The constitutive model adopted for the analysis is NorSand, which uses the state parameter Ψ.
Design Procedures Based on Experience
<p><p><strong>Current FHWA Reference(s):<br></strong> Schaefer et al. (2016b)<br><strong>Reference(s):<br></strong><em>Al-Alusi (1997)</em><em>Byle (2000)</em><em>Warner (2004)</em></p><p>This design approach is the preferred method and is the most commonly used in practice. The basis of this procedure is purely empirical and based upon past experience of specialty contractors and engineers. Typical site explorations are performed to characterize the subsurface conditions.
Design Procedures Based on Mathematical Modeling
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<p><strong>Reference(s):<br></strong><em>Al-Alusi (1997)<br>Basu (2009)<br>Schmertmann & Henry (1992)<br></em></p>
Route 85 and I-70, Maryland
<p><p><h2>Project Summary/Scope:</h2><div>An emergency repair of two roadways was conducted after a sinkhole formation was observed in a nearby storm-water retention pond and under the travel lanes of the two highways. Subsurface Conditions: The site was underlain by engineered fill and quarry run shot-rock placed on residual silty sand soils. The depth to bedrock was an average of 16.8 meters with a minimum of 7 meters and a maximum of 24 meters.</div><div> Compaction grouting was chosen to seal the bedrock and densify the overlying soils.
SPT/CPT Method
<p><p><strong>Reference(s):</strong></p><p><em>Bandimere (1997)<br>Graf (1992)</em></p><p><strong>Method Summary: </strong></p><p>This method has a very simple procedure. Typically SPT or CPT tests are run in the field to determine the initial site conditions. These may be converted to relative density based upon available correlations. Post-construction SPT and CPT tests should be run in relatively the same vicinity as those prior to the compaction grouting.
Trail Ridge Road, Colorado
<p><p><h2>Project Summary/Scope:</h2>The rehabilitation of a historic structural fill embankment along Trail Ridge Road in the Rocky Mountain National Park near Estes Park, Colorado was completed using compaction grouting. Cracking of the pavement section was observed, and settlements of 100 mm/year were measured. The settlements were attributed to piping around a nearby culvert.
Verification Using Seismic Methods
<p><p><strong>Reference(s):</strong></p><p><em>Haramay et al. (2009)</em></p><p><strong>Method Summary</strong></p><p>This is a newly developed non-destructive method known as High Definition Imaging (HDI). It involves collecting and analyzing seismic data pre- and post-grouting. It is relatively inexpensive, but requires some experience with geophysics and specialized equipment. 2-D and 3-D seismic refraction surveys are performed and processed into a volumetric 3-D assessment of the site.