<p><p><h2>Commentary</h2>The costs of using mass mixing methods on a highway project should be captured in a contract bid item measured by the cubic yard (CY). Included in this bid item are the material, equipment, labor, and incidentals to construct a shallow mixed column or create a mass stabilized soil volume. Mobilization, quality control, and load testing associated with shallow soil mixing and mass stabilization may be measured and paid for separately.<br><h2>Cost Information Summary</h2>The following table lists construction cost items that are associated with mass mixing methods, along with approximate cost ranges. Historical cost information for mass mixing methods in highway-specific applications is unavailable. However, shallow soil mixing is very similar to deep mixing methods. Therefore, cost ranges presented in this document are based on data from 2009 through 2011 for deep mixing methods, but the costs for mass mixing methods are expected to be lower than for deep mixing methods because the strength requirements are usually lower. Readers should carefully examine the project characteristics and constraints and determine to what degree, if any, these factors may influence the actual cost associated with treatment by the mass mixing method. Mobilization and labor costs for mass mixing are also expected to be less than for deep mixing. For many mass mixing applications, a working platform will be required. These costs should be included when comparing this technology with others. The cost of the geosynthetic for the working platform is provided in the Geosynthetic Reinforced Embankment cost information.</p><p><table class='tablepress' id='tablepress-105'><thead><th>Pay Item Description</th><th>Quantity</th><th>Unit</th><th>Low Unit Price</th><th>High Unit Price</th><th>Factors Which May Potentially Impact Costs</th></thead><tbody><tr><td >Shallow Soil Mixing</td><td >Greater than
5000
</td><td >CY</td><td >$60.00</td><td >$125.00</td><td >Cost range stated applies to the dry method
Cost of binder materials is sensitive to material
specifications and haul distance
Unit costs will decrease as depth increases</td></tr><tr><td >Mobilization </td><td >1</td><td >LUMP
SUM</td><td >$15,000</td><td >$40,000</td><td >Hydraulic excavator-mounted attachments (mass
stabilization) can be used for depths up to 7 meters
Crane mounted augers (shallow soil mixing) are
used for depths up to 12 meters
Mobilization cost increases for distances greater than
500 miles
Phased projects may require multiple mobilizations</td></tr><tr><td >Embankment</td><td >Greater than
5000
</td><td >CY</td><td >$-</td><td >$-</td><td >Use historical costs that are representative of the
project quantity, project conditions, and project
location</td></tr></tbody></table><h2>Historical Cost Information</h2>No cost history from highway construction projects is available. A sample of actual project costs for deep soil mixing is shown in the table below.</p><p><table class='tablepress' id='tablepress-106'><thead><th>Pay Item Description</th><th>Quantity</th><th>Unit</th><th>Low Unit Price</th><th>High Unit Price</th><th>Average Unit Price</th><th>No. of Bids</th><th>Bid Date</th><th>Source/Agency</th></thead><tbody><tr><td >Deep Soil Mixing, Dry</td><td >4,867</td><td >CY</td><td >$79.12</td><td >n/a</td><td >n/a</td><td >1</td><td >4/29/2009</td><td >Florida DOT</td></tr><tr><td >Ground ImprovementDeep
Soil Mixing Lime
Cement Columns T-1</td><td >22,770</td><td >CY</td><td >$60.00</td><td >$92.12</td><td >$70.59</td><td >7</td><td rowspan=2 >1/8/2011</td><td rowspan=2 >South Carolina DOT </td></tr><tr><td >Ground ImprovementDeep
Soil Mixing Lime
Cement Columns T-2
</td><td >12,799</td><td >CY</td><td >$62.80</td><td >$122.60</td><td >$83.49</td><td >7</td></tr></tbody></table><h2>Conceptual Cost Estimating Tool</h2>The conceptual cost estimating tool is intended to be used to develop a preliminary project scoping cost estimate. This preliminary estimate can be based on the typical construction cost item values as contained in the Cost Information product or from user specified cost values when such are known. Users should read and understand the information in Cost Information product prior to using the cost estimating tool. You can download the Cost Estimating Tool to open a cost estimating spreadsheet for producing a preliminary project scoping estimate.</p><p><a class="arrow-link" href="https://www.geoinstitute.org/sites/default/files/geotech-tools-uploads/… the Cost Estimating Too</a>l</p></p>