3214 BROADWAY Geotech Report 2022-10-25

American Property Development ES-0599.06 June 9, 2016 Page 10 Revised October 16, 2017 Tieback anchors should be verification tested and proof tested in general accordance with Section 8.3 of the Recommendations for Prestressed Rock and Soil Anchors (Post-Tensioning { Institute, 1996). A minimum of two verification tests (200 percent design load) should be performed. Verification test anchors can be used as production anchors, provided the anchor is successfully tested and is acceptable. The production anchors should be proof tested to 130 percent of the design load. The geotechnical engineer should observe the anchor testing and provide documentation of the test results. Tieback anchors should be locked-off at 90 percent to 100 percent of the design load. Shoring Wall Drainage E Temporary shoring walls should be provided with adequate drainage to reduce the potential for excess hydrostatic pressure build-up. During construction, drainage occurring between the timber lagging is usually sufficient to prevent the development of excessive hydrostatic pressures. Where permanent building walls will be constructed along the temporary shoring walls, a sheet drain material should be installed along the face of the shoring wall. A typical detail illustrating a sheet drain and permanent wall drainage system is provided on Plate 6 of this study. Shoring Monitoring Due to the close proximity of adjacent buildings and public right-of-ways, an optical monitoring program should be implemented for this site. The monitoring program should consist of a video or photo survey prior to beginning the building excavations to document the current conditions of the surrounding features. Initial survey points should be placed at strategic locations along adjacent foundations and right-of-way alignments that will allow for periodic measurement during and after the shoring installation. This will allow for efficient monitoring of the site to identify and remediate excessive deflections or excavation related movements, if they occur. Prior to the start of construction, the geotechnical engineer, owner, and contractor should review the project and develop a monitoring program for the site. Following installation of the soldier piles (if utilized), monitoring points are typically established on the top of the piles prior to proceeding with the excavation. An initial baseline reading should be acquired prior to proceeding with the excavation. Readings should be acquired relatively frequently during the excavation phase of the construction. The geotechnical engineer should review the data as it becomes available during the course of construction. The monitoring program should be supplemented with periodic observations by the geotechnical engineer during the excavation phase of construction. Earth Solutions NW,LLC