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3.3 SUBSURFACE EXPLORATION Characterization of subsurface conditions and parameters for design and construction of deep foundations requires an adequate subsurface investigation and testing program. Such a program consists of field investigations and testing,
including in-situ testing, and laboratory testing of recovered soil and rock samples. These are described briefly herein with emphasis on considerations for laterally loaded deep foundation design.
3.3.1 Subsurface Exploration Program Requirements Data for the foundation design should be obtained
from a subsurface exploration, consisting of field investigation and testing techniques. The subsurface exploration will depend on the type of structure,
or application, and the site variability. Table 3-3 provides recommendations regarding the minimum number of exploration points for the design of deep foundations for lateral loading applications. The requirements presented in Table 3-3 are consistent with general recommendations for deep foundation design. Exploration points typically consist of soil and rock borings, but may also include other types of in-situ exploration techniques.
Table 3-3: Minimum number of exploration points and depth requirements for deep foundations subject to lateral loads (modified from AASHTO 2014 and Loehr et al. 2016). Share with your friends: 
