4129 GRAND AVE 2016-01-01 MF Import

Geotafioical f¢�aitipbm WES7ERN (iFA'IF.CHNICAL CONSULTANI'S. INC. 4129 (h�odAvmue, EvaeU, WA Juty 14, 2000 (page 3 of 6) piers, exclusive of the'v weig6t. T6is load value may be increased by an amount of one- third for transient wind or xiamic loading. Assuming conswctiun is accompiiahed as recoron►ended and for the soil conditions and anticipated loads, we estimate totd settlement of tLe pier foundations should be less than 1 inch and diffaential sdtlementa betwan adjacent Piera should be about half of that amount. We expect moat of the xtHement will take place rather rapidly during construction, due to t6e graztular nature of the foundation soils. The stcuctural eng�neer s6ould provide concrcte strongth and stal reinforcement rxommendations for the pier foundations. : n�-�xc�vation and Renlacement with �■ Soalls As an altanative to piers, the peat soils could be overexcavated and removcd down to the sand layer and be replaced with quarry spalls. This would allow for a conventionai shallow foundation system. To provide adequate support, however, the quarry spall base waild 6ave to extend outward on each side o:' a foundadon element at a'h horizontal : 1 vertical angle (or flatter) down to the SAND layer. Conventional ahallow foundations would be suitable for this altemative using footing dimeesions and loading specified in the Uniform Bnilding Code ([JBC) for a singlo-story swcxure. Given the depth of the o��erexcavation required, however, this altemative may not be feasible. Conetruction Considentiona Sonotubes may be used as forms for placing the roinforced concrete piers. M excavator or backh�e may be used to dig down to the foundation level before placing the sonotubes. PTote tba� some ground water seepage may be encountered during coeswction. If a signiP,cant amount of water accumulates during placement of the piers, it will have to be pumped out. Also, thero may be some variation in the depth to the wmpact sanda. It is importaet that an inspection is performed initielly during foundation construction to verify the soil wnditions and to ensure the placement of tlie piers satisfy our recommendations. The on-site soils may be used for backfill provided they will not have to support load bearing stmctures, including floor slabs, or other suuctural improvements. The final ground surface should be graded 'o allow surface water to easily drain away from the house.