Bearing Capacity Clause Samples

Bearing Capacity. When correlated to the estimated rock compressive strengths determined from the point load index tests, the allowable bearing pressure for foundations bearing directly on sound bedrock is typically in the range of 1/3 to 1/10 the unconfined compressive strength (▇▇▇▇▇▇, p. 278). Presumptive allowable bearing pressures for granite published in Fang, 1991, Table 3.8, range between 30 and 60 tsf. We estimated theoretical bearing capacity values on the order of 500 tsf using equations and correlations found in ▇▇▇▇▇▇. However, based on our observations of the bedrock conditions and our experience at similar sites, we recommend an allowable contact bearing pressure of 15 tsf (ASD design) or factored bearing resistance of 20 tsf (LRFD design) for strength limit state analyses be used for compression loads for design. We recommend a minimum footing width of 3 feet regardless of footing pressures for individual tower leg foundations if a large pier pad is not used. In no instance shall the maximum footing pressure exceed the allowable concrete bearing stress, regardless of the bedrock bearing capacity. To verify that the foundation bearing conditions are consistent with our findings in the boring exploration, we recommend that the exposed footing subgrade be observed and approved by an experienced engineer or geologist.