<p><p><strong>References:<br></strong><em>Al-Homoud and Degen (2006)</em></p><p><strong>Method Summary</strong></p><p>Stone column performance is also dependent on the verticality of the column. X-Y sensors can be mounted on the rig to ensure verticality during installation. Visual inspection of rig verticality and/or a level can also be used.</p><p><strong>Accuracy and Precision</strong></p><p>Visual inspection of verticality can be subjective and difficult to perform, however levels and/or X-Y sensors can be used to improve the accuracy of determinations.</p><p><strong>Adequacy of Coverage</strong></p><p>Continuous monitoring of rig verticality can provide an indication of the verticality profile of the entire column.</p><p><strong>Implementation Requirements </strong></p><p>No special equipment is required for this method.</p><p><strong>General Comments</strong></p><p>Column verticality is important for all stone column applications.</p></p>