Chance Technical Design Manual

REINFORCEMENT DETAILS FOR CASE STUDY #2, FIGURE 9-17

continuously spaced 8” diameter plates along the entire length of a 1-1/2” solid square steel shaft. The Soil Screw® Anchor will be installed to a minimum length of 14 feet, 10° down from horizontal and to an es timated torque of 1,800 ft-lbs. • Soil Screw® Anchor Row #3 (T3): C1100692 Lead and C1100690 Extension. The Soil Screw® Anchor has continuously spaced 8” diameter plates along the entire length of a 1-1/2” solid square steel shaft. The Soil Screw® Anchor will be installed to a mini mum length of 10 feet, 10° down from hori zontal and to an estimated torque of 1,000 ft-lbs. SHOTCRETE WALL The shotcrete wall is a temporary facing for the excavation. Since the soil analysis assumed that the Chance® Helical Tieback Anchors do not contribute to the holding capacity of the body mass of soil (see Figure 9-8), the Chance® Helical Soil Screw® Anchors were designed to hold the total body mass. The bottom cantilever should be limited to 2/3 of the typical spacing for the Soil Screw® Anchor row, but should not exceed 3 feet. In this case the cantilever is 3 feet. Vertical bearing bars are extended from the welded rebar head assemblies at the upper row of Soil Screw® Anchors to the dowels and waler at the top of the wall in order to augment the selected shotcrete wall thickness (5”). Welded wire fabric reinforcing (WWF 6x6 W2.9 or equivalent) is spaced midway within the shot crete wall at a 2-1/2” nominal depth. The top wall segment is checked for flexure and shear using the distributed Soil Screw® Anchor head forces

RETENTION WALLS

EXCAVATION AND STABILIZATION FIGURE 9-18

Hubbell Power Systems, Inc. | All Rights Reserved | Copyright © 2023 | Page 9-15