TDOT SR-108 Landslide Repair - Anchored Soldier Pile and Tie Back System-PPT Presentation

PPT Presentation

Pdf Summary

The presentation describes TDOT’s investigation and design work for a landslide along SR-108 near Chattanooga. The slide extends roughly 1,500 feet along the roadway. Landslides were mapped in the area as early as 1973; the roadway was shifted closer to the uphill cut in 1992, and drainage work was completed in 2007 as a temporary mitigation measure.<br /><br />TDOT requested geotechnical services in September 2020. The work included site meetings, two phases of drilling, and geophysical testing. Exploration included borings, piezometers, and inclinometers, with drilling conducted using several types of rigs and methods. Testing included Multi-Channel Analysis of Surface Waves, Seismic Refraction Tomography, and Electrical Resistivity Imaging. The site’s geology includes sandstone, shale, siltstone, limestone, and dolomite in formations of Pennsylvanian and Mississippian age.<br /><br />The proposed stabilization is an anchored soldier pile wall, approximately 40 feet high. The design uses HP 18x135 piles spaced 10 feet apart, with multiple rows of inclined ground anchors. The number of anchor rows varies along the wall alignment.<br /><br />The final geotechnical report has been submitted, and the structural engineering team is continuing design work. Construction letting was expected later that year.

Keywords

TDOT

SR-108

Chattanooga

landslide

geotechnical investigation

anchored soldier pile wall

ground anchors

drilling

geophysical testing

slope stabilization