Loading...
HomeMy WebLinkAboutStudies APPLICANT 4/20/2023 (2)Geotechnical . Environmental. Special Inspections 11911 NE95"Street °uer,Washington 98M1Columbia West Pana: 25,00 E in g i in e e r i in g I in c March 15, 2023 Oregon Urology Institute Radiation Center 1457 G Street Springfield OR 97477 Attn: Patrick Aldinger, R.T. (R)(T) Re: Report of Geotechnical Engineering Services Oregon Urology Institute Radiation Center Addition 1457 G Street Springfield, Oregon CWE Project No. 23092 INTRODUCTION We are pleased to provide this letter report for the proposed addition to the Oregon Urology Institute Radiation Center located in Springfield, Oregon. The project includes adding a concrete vault to the north side of an existing vault. The proposed addition has footprint of approximately 1,500 square feet. The weight of the structure is approximately 2,000 kips. The perimeter concrete walls are supported on a 5 feet wide footing that carries approximately 15 kips per foot. K & A Engineering, Inc. (KAE) conducted a geotechnical site study for use in design and construction of original facility. Theirfindings are presented in a geotechnical engineering report dated September 19, 2006. A copy of this report is presented in the Attachment. We used the subsurface information presented in that report to provide geotechnical engineering recommendations for use in design and construction of the proposed addition. SCOPE OF SERVICES The purpose of our work was to provide geotechnical engineering recommendations for foundation support of the proposed addition to the Oregon Urology Institute Radiation Center. Specifically, we propose the following tasks: • Reviewed the above -referenced geotechnical report. • Reviewed readily available information in our files from previous geological and geotechnical studies conducted in the site vicinity. • Provided recommendations for foundation support of the proposed addition focusing on the use of rammed aggregate pier ground improvement. at Prepared this letter report that presents our findings, conclusions, and recommendations. SUBSURFACE CONDITIONS KAE's subsurface exploration plan consisted of drilling 2 borings to depth of 31.5 feet and 20 feet below ground surface (bgs). The boring logs and boring locations are provided in the Attachment to this report. Geotechnical •Environmental •Special Inspection • Materials Testing ww wlumbiawestengiaeering.com Geotechnical Engineering Services Page 2 of 4 Oregon Urology Institute Radiation Center Addition KAE's explorations encountered silt to a depth of 9 and 10 feet in each of the borings, respectively. They describe the silt as stiff based on standard penetration tests (SPT's). The silt is underlain by gravel to the maximum depth explored. Based on SPT's the gravel is described as dense. An interbedded sand layer was encountered in each of the borings at a depth of 21 feet and 18 feet in the borings. The sand layer appears to be approximately 5 feet thick. It was reported that the sand heaved during sampling and therefore we believe that the SPT blow counts are artificially low and do not represent the in-situ relative density of the sand. This is common below the groundwater table when borings are drilled using hollow stem auger methods. Based on our experience in the site vicinity we believe the sand layer to have a relative density in the dense to very dense range. Groundwaterwas reported to be at a depth of 12 feet bgs at the time of drilling. SEISMIC CONSIDERATIONS In our opinion the soil profile at the site is consistent with Site Class D as defined in ASCE 7-16. Based on our understanding of subsurface conditions liquefaction and associated lateral spreading are not considered hazards. FOUNDATION SUPPORT RECOMMENDATIONS We understand that the spread footings will be supported on ground that is improved with rammed aggregate piers (RAP'S). In our opinion this is an acceptable means of supporting the proposed addition. RAP's are a ground improvement system that consist of installing compacted aggregate that reinforces and improve the soil. In general, RAP's consist of 2 -to 3 -foot -diameter drilled holes backfilled with compacted crushed rock. The crushed rock is placed in the hole in lifts and compacted. Aggregate pier foundations are typically designed and constructed by specialty contractors. The allowable bearing pressure for shallow foundations supported on rammed aggregate piers is typically 6,000 to 7,000 psf. This value can typically be increased by one-third to one-half when considering transient loads such as wind and seismic forces. The design -build contractor should be contacted to provide the actual allowable bearing pressures and aggregate pier configurations they recommend for this project. If aggregate piers are used for this project, we recommend that Columbia West be allowed to review the final design and proposed installation methods. We should also be present during installation of production piers to confirm that soil conditions are as anticipated. 691:i49O1:7_1�y14 Structural fill includes fill beneath foundations, slabs, pavements, any other areas intended to support structures, or within the influence zones of structures. Structural fill should be free of organic matter and other deleterious materials and, in general, should consist of particles no larger than 3 inches in diameter. All structural fill should be compacted to at 95 percent of the maximum dry density as determined by ASTM 1557. All structural fill placed with influence of RAP's should be approved by the RAP designer. Geotechnical •Environmental •Special Inspection •Materials Testing www.columbiawestengineering.com Geotechnical Engineering Services Page 3 of 4 Oregon Urology Institute Radiation Center Addition OBSERVATION OF CONSTRUCTION Satisfactory earthwork and foundation performance depends to a large degree on the quality of construction. Subsurface conditions observed during construction should be compared with those encountered during the subsurface explorations. Recognition of changed conditions often requires experience; therefore, qualified personnel should visit the site with sufficient frequency to detect whether subsurface conditions change significantly from those anticipated. In addition, sufficient observation of the contractor's activities is a key part of determining that the work is completed in accordance with the construction drawings and specifications. LIMITATIONS We have prepared this report for use by Oregon Urology Institute and their dsign and construction team. The data and report can be used for estimating purposes, but our report, conclusions, and interpretations should not be construed as a warranty of the subsurface conditions and are not applicable to other sites. Soil explorations indicate soil conditions only at specific locations and only to the depths penetrated. They do not necessarily reflect soil strata or water level variations that may exist between exploration locations. If subsurface conditions differing from those described are noted during the course of excavation and construction, re-evaluation will be necessary. The scope of our services does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractor's methods, techniques, sequences, or procedures, except as specifically described in our report for consideration in design. Within the limitations of scope, schedule, and budget, our services have been executed in accordance with the generally accepted practices in this area at the time this report was prepared. No warranty or other conditions, express or implied, should be understood. Geotechnical •Environmental •Special Inspection •Materials Testing www.columbiawestengineering.com Geotechnical Engineering Services Page 4 of 4 Oregon Urology Institute Radiation Center Addition We appreciate the opportunity to be of service to you. Please call if you have questions concerning this report or if we can provide additional services. Sincerely, COLUMBIA WEST ENGINEERING, Inc. pamayrxi BrettA. Shipton, P.E., G.E. Principal Geotechnical •Environmental •Special Inspection •Materials Testing www.columbiawestengineering.com ATTACHMENT GEOTECHNICAL ENGINEERING STUDY BY OTHERS This attachment presents a geotechnical engineering report prepared by K&A Engineering for use in design and construction of the existing Oregon Urology Institute located in Springfield, Oregon. The report is titled: Preliminary Geotechnical Site Investigation Report, 1457 G St. Tax map 17033622, Tax lot 6800, Springfield, Oregon, dated September 19, 2006. k*a engineering September 19, 2006 Mr. Terry Fitzpatrick, Administrator Urology Healthcare, P.C. 2400 Hartman Lane, Suite 200 Springfield, OR 97477 Subject: Preliminary geotechnical site investigation report 1457 G St., Tax map17033622, Tax lot 6800 Springfield, Oregon K & A Engineering, Inc. 3327 Roanoke Ave., Eugene, OR 97408 (541) 684-9399 Voice (541) 684-9358 FAX Project: 180.06 PURPOSE AND SCOPE As requested, K & A Engineering, Inc. has completed a geotechnical site investigation of the subject project site. The purpose of this investigation was to determine is the she was suitable for the proposed development. The scope of our services Included making geotechnical borings, reducing the data from the borings, and this brief summary report. SITE INVESTIGATION AND FINDINGS General Site Characteristics The project site is located in the south-central area of town, south of the existing McKenzie -Willamette Medical Center. The site is currently the location of a wood -framed single -story medical office building surrounded with a paved parking lot. The existing ground surface is essentially flat with no remarkable topographical relief. It is important to note that there appears to be a large underground Fuel storage tank located along the south side of the existing building foundation. Control valves and piping appear to be routed to what may have been a generator located in the building. We also noted that sanitary sewer and electrical service am currently located underground running from the south property boundary to the south foundation of the existing building. The mapped geology of the project site consists of quaternary delta deposits that include silts, sands, and gravels having a variable depth over weak sedimentary sandstones and siltstones of the Eugene formation.' This is consistent with the findings in our geotechnical borings (see below). Groundwater can characteristically be moderately high (within 10 -feet of the ground surface). Subsurface Soil Conditions Two borings were made at the site. Our proposal was for four shallow borings with the assumption that we would possibly encounter bedrock within 20 -feet. Bedrock was not encountered and the decision was made to ' Ian P. Madin and Robert B. Murray, Preliminary Geologic Map of the Eugene East and Eugene West Quadrangles, Lane County, Oregon, Open -File Report OFR 0-03-11,.Oregon Department of Geology and Mineral Industries. 2004. K & A Engineering, Inc. attempt to extend two borings to depths greater than 20 -feet. Seethe attached Geotechnical Site Plan for locations of these borings. Graphic logs of the borings are attached to this report. The soils and groundwater in each boring were remarkably consistent and included approximately 1 -foot of asphalt pavement and crushed rock base over 8 -feet of brown stiff moderately plastic silt over very dense poorly graded sandy gravels and poorly graded gravelly sands. Groundwaterwas at approximately 12 -feet below the existing ground surface. Boring DH1 was successfully extended to a depth of 31.5 -feet. Boring DH2 was extended to a depth of 204eet before sands welling into the auger casing prevented further sampling and testing. The borings were sealed with bentonite and capped with concrete after completion of the borings. SUMMARY AND RECOMMENDATIONS General Suitability We recommend that the site Is suitable for the proposed construction It is our understanding that the proposed construction includes a vault for medical laboratory testing constructed of very thick concrete that will have extremely high dead loads. The very dense gravelly sands and sandy gravels found at a depth of approximately 9 -feet below the existing ground surface will provide an extremely high bearing capacity. For extremely high loads we would not recommend supporting foundations on or in the upper layer of brown sit. Recommended Foundation Type Depending on the grades and size of the structure, suitable foundation types could include spread footings supported by a controlled granular fill that Wends from footing grade to the dense gravelly sands or sandy gravels. Alternatively the structure could be supported by a grade beam system supported by piles, piers, or rock columns that extend into the dense gravelly sands or sandy gravels. Geologic Hazards The site presents no significant hazard associated with liquefaction due to the dense nature of the underlying granular fills. There are no other unusual geologic hazards at the site. Additional Geotechnical Recommendations Design of the proposed structure and associated utilities and other improvements will require additional geotechnical recommendations. These recommendations were not part of our scope of work for this contract. K & A Engineering, Inc. would be happy to provide a detailed geotechnical report with design and construction criteria. We thinkthatthe data gathered from our borings forthis report are adequate to develop detailed recommendations including bearing capacity and estimates of settlement and that no further site investigation will be necessary. Please contact our office when additional geotechnical design criteria or other assistance is required Project: 180.06 1457 G. St, Springfield, OR Page 2 of 3 Client: Urology Healthcare, P.C. August 9, 2006 K & A Engineering, Inc. LIMITATIONS OF THIS REPORT This report has been prepared for the exclusive use of Urology Healthcare, P.C. and Its design consultants for the subject proposed structure. This geotechnical investigation, analysis, and recommendations meet the standards of care of competent geotechnical engineers providing similar services at the time these services were provided. We do not warrant or guarantee these recommendations, she surface, or subsurface conditions. Exploration test holes inchoate soil conditions only at specific locations (i.e. the test hole locations) to the depths penetrated. They do not necessarily reflect soilrock materials or groundwater conditions that exist between or beyond exploration locations or limits. The scope of our services does not include construction safety precautions, techniques, sequences, or procedures, except as specifically recommended in this report. Our services should not be interpreted as an environmental assessment of site conditions. Thank you for the opportunity to be of service. Please callus ff you have questions or need further assistance Sincerely, WIRES Michael Remboldt, P.E. K & A Engineering, Inc. Project: 180.06 1457 G. St, Springfield, OR Page 3 of 3 Client: Urology Healthcare, P.C. August 9, 2006 geotechnical/civil Project: 1457 G. St., Springfield, OR 9c3engineering Client: Urology Healthcare, P.C. Eugene, OR 97408 Job No: 180.06 Date: 8/16/2006 e 5 e el 9 k541 684 9399 541 684 9358 fax Sheet: 1 of 1 G STREET ----- - I. ... . ... I t APPROX. PROPI i 1 LOCATION OF DRILL HOLES 8/16/2006 --------- 1 i I I I I EXPIRES 1 I � � I I --------- 1 i I I I I EXPIRES The stratiflcatian lines represent approximate 100ngansa. I lie nanaNun may uv y, auua,. K &A Engineering, Inc. 3327 Roanoke Ave. ka Eugene, DR 97408 LOG OF BORING DH1 Telephone: (541) 684-9399 Sheet 1 of 1 ,� heerin Fax: 541 684-9399 project: Urology Healthcare, P.C. Top of casing Eley.: WATER LEVELS Job No.: 180.06 Drilling Method: H.S. Auger While Drilling: Location: 1457 G Street, Springfield, Oregon sampling Method: Split Spoon End of Drilling: Q 1 hm After Drilling: 12.0 CooMinatea: rn w Z v STANDARD PENETRATION WELL v MATERIAL DESCRIPTION TEST DATA INSTALLATION E m o Ninnl.Wft0 DETAILS o m y a' mg Surface Eler : m m m - D s halt avemenf Crush Sd a re e mmun, Brown, damp to moist, stiff, motlemlely plastic SILT. 5 I 1 67 5 < 2 87 4 4 IX 3 93 4 7 Darkgmy, moist to satureted, very dense, poorly 10 oB' graded SANDY GRAVEL _ 4 5U La 4 4T. o�D 5 53 20 15 .o`D: 24 Q" 6 53 18 a. p�q 20!" n _D: 23 a y, 4: 7 6010 s Dark gray, saturated, dense, paady graded o GRAVELLY SAND .Q �a p: is ?5 6 93 is so Gmy, saturated, very dense, poorlygraded SANDY a{}° GRAVEL bi Q ' g ,�a o .D: 30 20 60 e 40 I 9 i..11i o e Com_Ierci Depth: 31.5 Semple Types: Remarks: rc nate Goring Started: BH 6106 Auger Cutting Shelby Tube m Date Boring Completed: BH6/D6 Vane Shear Grab Lagged 0y. MOR Spill Spoon Rork Care o Drillin Contractor. PNW nrillln The stratiflcatian lines represent approximate 100ngansa. I lie nanaNun may uv y, auua,. K & A Engineering, Inc. 3327 Roanoke Ave. ea Eugene, OR 97408 LOG OF BORING DH2 Telephone: (541)684-9399 .� Inzerin Fax: 541 684-9399 Sheet 1 of 1 Project: Urology Healthcare, P.C. Top or=ird Eay.: WATER LEVELS hile Drilling: rEnd Job No.: 180.06 Drilling Methotl: H.S. Anger Location: 1467 G Street, Springfield, Oregon Sampling Method: Split Spoon of Drilling: Coordinates: 3 his After Drilling: 12.0 - um Z _ m =s 9TANUARp PENENtATION WELL $ MATERIAL DESCRIPTION TEST DATA INSTALLATION Nis bbw a, DETAILS W r11 a so 6 Surface Marv.: ro zo m m m 0 As halt0 avement a re ate base Ertlamp to moist, stiff, moderately plastic SILT. Erma, 4 1 60 4 5 4 2 93 4 6 4 3 100 4 grey, moist to saturated,very dense, poorly10 ?Dark ? ° graded SANDY GRAVEL 29 4 80 se Q: 49 36 S 40 9 0 24 6 67 32 e,Ftc 33 PLJb ASSUMED poorly graded SANDS or GRAVELLY ;Q SANDS. Sands welled Into auger preventing sampling or standard D.n.tratlon testln . 20 i i i 3 3 4 Completion Depth; 20.0 Sample Types: Remarks: Data Boring Started: wie— o Auger Cutting Shelby Tub® Date Dining Complatetl: B/1fi/06 Vane Grab Logged By: MDR Drillin Contractor. PNW Drillin poohhea Spilt Spoon Rock Core Thestratigcation lines representappmximate boundaries. The transition maybe gradual.