2118 JEFFERSON PL 2024-10-25 - Laserfiche WebLink

3 of 31 A PROJECT NO. SHEET NO. S230503-2XR PROJECT 2118 Jefferson PI Everett WA 98203 LONGITUDE SUBJECT Foundation Stabilization/Jacking ONE TWENTY° ENGINEERING&DESIGN BY JT DATE 08/29/2023 Scope/Objective: To determine the required pile spacing and geometry to stabilize and lift(where required)the existing structural foundation. These findings have been based upon the calculated strength of the existing foundation system and the current vertical loading from the existing structure above(based on as-built assessments). The R&R Foundation Specialists'(R&R)proposed pile layout can be found in the following pages with structural recommendations based upon the findings of L120 Engineering&Design. Note that cosmetic damages to rigid wall coverings/members and siding are expected during a foundation lift. Such cosmetic damages/cracks are to be repaired by others following the completion of the foundation stabilization and lifting and are not included in the structural scope presented here. It should be further noted that L120's scope is limited to the perimeter support systems/continuous footings.The interior crawl-space support system for the first floor shall be installed per R&R. This could include the use of some or all of the following: longer support posts,adjustable post-base hardware,and/or the addition of taller wood support members. Settlement in these interior support areas shall be monitored and further adjustments shall be made if necessary. Structural Summary: -The foundation of the residence consists of continuous cast-in-place concrete stem wall and concrete strip footings. Below the footings, piles are to be spaced at a distance no larger than 8'-0"o.c.w/the installation of supplemental C6x8.2 channel as indicated on the attached Level Survey. -End piles shall not exceed the maximum corner offset as specified on the attached Level Survey. -A maximum allowable loading of 1,450 plf was utilized in this analysis.This was determined through inspection of building geometry and conservative span/tributary loading assumptions based on standard construction practices - The following load values represent the maximum expected pile loads for the indicated spacing. R&R to provide pile and equipment assemblies with capacities equal to or greater than the indicated load values. Allowable Load Capacity Requirement: Helical Pile#1-2,5 @ 8'-0"o.c. 5.0 kip minimum vertical capacity(allowable load) Helical Pile#3-4 @ 8'-0"o.c. 7.0 kip minimum vertical capacity(allowable load) Helical Pile#6-7 @ 7'-0"o.c. 11.0 kip minimum vertical capacity(allowable load) Helical Pile#8-9 @ 8'-0"o.c. 10.0 kip minimum vertical capacity(allowable load) Note: Refer to the attached General Notes for additional requirements. - As determined by R&R,the site appears to have no lateral(horizontal)displacements or concerns. As such,the analysis and recommendations presented in this report have been strictly limited to vertical stabilization/jacking. If lateral movement is observed or expected additional structural analysis will be required. - Structural recommendations contained in this package are based on site photographs dated August 25th,2023,provided by R&R.To the knowledge of L120,a geotechnical investigation was not performed on this site.Consequently,all structural recommendations assume adequate soil conditions to obtain the required pile capacities. Please inform L120 of site-specific conditions that were unconsidered by, may conflict with,or otherwise compromise the recommendations contained within this package, including,but not limited to,water drainage,slope stability,existing structural damage, or existing subsurface obstructions. In this instance,the structural assumptions, recommendations,and scope for this project will need to be revisited to consider and address the new findings Refer to the following pages for pile and connection specifications. L120 ENGINEERING&DESIGN