1001 39TH ST 2016-01-01 MF Import

r. _. i DAVID L. NELSON AND ASSOCIATES, INC. Consulting Enginecring Geology i November 27, 1991 Project No. 10591 Page 9 1 . All footings should be founded into the native site soils, structural fill, ur crushed rock, as described above. 2 . All footing excavations should be prepared such that a dense, nonyielding, uniform soil condition has been established prior to placement of footing concrete . i 3 . All footings should extend through any existing loose � . native soil, non-structural fill or modified zones and be placed to bear a minimum of 18 inches below finished a3jacent grade. � 4. All footings should be sized according to the � anticipated wall or column loadings, and the above soil • bearing values. tdinimum footing widths cf 14 and 20 inches are recommended for all continuuus and isolated footings, respectively. 5 . All foot�ngs should be free of ponded water, sloughed I soils and water loosened soils prior to placement of footing concrete. I We recommend that footing areas be inspected by a geotechnical �i consultant prior to placement- of concrete to verify that bearing i soil type and conditions are consistent with the reconunendations of this report. Ground settlements due to strvctural loads should be less than one ( 1 ) inch total ar.d one-half ( 1 /2) inch I�, differential over the building area. � D�aring periods of wet weather or in saturated soil con�itions, special measures may be required to facilitate construction. Interim excavation grading should be sloped to prevent ponding. i It should be noted that the on-site surface soils and weathered zone materials are considered highly moisture sensitive, and may tend to deteriorate if worked during rainy weather or in a saturated condition. Delays in construction activity may result from a deteriorated soil condition. If necessar.y, the use of a covering of crushed rock or pit run gravel over the subgrade soils is recommended to minimize disturbance and softening of the bearing soils during construction. The thickness of the rock or gravel will be dependent on the material being protected, and its use. Pressures On Subgrade Walls (Retaining Walls) The design lateral earth pressures acting on retaining walls are a function of the type of wall ( for example, yielding or non- yielding) , the method of construction, and the type of soil used � 'rcn