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M98168GE ~ • square foot with a minimum depth of embedment into the formational material of at least one (1) foot. The bearing capacity may be increased by about 20 percent for transient loads such as wind and seismic loads. The minimum depth of embedment is sufficient only to develop the bearing capacity for design purposes. Actual design and construc- tion should result in interior footings with one (1) foot or more embedment and exterior footings with frost depth or more embedment. Typically deeper embedment will increase bearing capacity and de- crease poet construction settlement and decrease the influence of expansive soils. Interior column loads supported on spread footings which are structurally connected to the other foundation members will provide more uniform performance of the interior footings with respect to the other foundation members and will help reduce the potential differential settlement between interior and exterior foundation members. The foundation walls should be designed to act as beams to distribute stresses associated with the swelling soils. The beam design should be addressed by the project structural engineer. Exterior column supports should be supported by foundations incorporated into the foundation system of the structure not supported on flatwork. Column supports placed on exterior concrete flatwork may move if the support soils below the concrete slab-on- grade become wetted and sweJ~. or freeze and raise or settle. Differential movement of the exterior columns may cause stress to accumulate in the supported structure and translate into other portions of the structure. If the foundations are supported on undisturbed formational material and are designed and constructed as discussed above we anticipate that the poet construction total settlement may be about 1/2 inch. The settlement values above are appropriate for footings with a width of about eleven (11) feet or less. Larger footings should be analyzed on a footing, load and width specific basis. The calculated settlements are theoretical only. Actual settle- ment could vary throughout the site and with time. Due to the very hard nature of the formational material, we anticipate that the samples of the formational material may have been somewhat disturbed during the sampling process. The swell and 12 Lambert ana ~a~ociate~ COMWLTIMO O[OTlOMYIOl1l lMOA[[p BYO Y~Tl114~ TF[TIMO