PROPOSED CONDOS 1129 Victoria Drive, Dunedin Parcel: , Pinellas County Geotechnical Services June Report No.

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1 Central Florida Testing Laboratories, Inc. Testing, Development and Research th Street North Clearwater, Florida ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO. 224 TAMPA BAY AREA (727) FLORIDA CFTL FAX (727) 299- PROPOSED CONDOS 1129 Victoria Drive, Dunedin Parcel: , Pinellas County Geotechnical Services June 2018 Report No A Prepared for Laura and Brian Maiocco P.O. Box 575 Crystal Beach, Florida 34681

2 Central Florida Testing Laboratories, Inc. Testing Development and Research TH STREET NORTH CLEARWATER, FL ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO. 224 TAMPA BAY AREA (727) FLORIDA CFTL FAX (727) June 14, 2018 Laura and Brian Maiocco P.O. Box 575 Crystal Beach, FL Re: Addendum to Geotechnical Recommendations Proposed Condos Victoria Drive, Dunedin, Florida (Parcel: , Pinellas County, Florida) CFTL Report No A Dear Mr. and Mrs. Maiocco, As requested, we are providing deep foundation recommendations based on the soils data generated by our previous geotechnical investigation of the above referenced property. Our report issued April 19 th, 2017 found that soils underlying the property could be used for supporting shallow foundations and recommendations were presented for their use. We now understand that the proposed condominiums are to be constructed as though they were in a FEMA VE zone which would require the use of a pile and grade beam foundation for support. Therefore, this addendum is providing recommendations for the use of a pile foundation for support of the proposed new buildings. This addendum includes recommendations for the use of treated timber piling and the use of augercast, cast-in-place concrete piling. It should be noted that we recommend that structural timber piling used beneath the waterfront location of the subject property should comply with ASTM-D25-99(2005) specifications and should be treated for marine use. For review by your contractor and piling installation subcontractor we are providing in this addendum report information from our previous report including a site description for the property, all location maps, a FEMA zoning map, the Site Plan, the boring logs from our prior testing, and the descriptions of the soils encountered in each boring.

3 Laura and Brian Maiocco Addendum for Proposed Condos Victoria Drive, Dunedin, Fla. CFTL Report No A Page 2 Site Description The subject property is located between Broadway Street (Alt. U.S. Hwy 19) to its east and Victoria Drive to its west approximately 1/2 mile to the north of Main Street (SR 580) in Dunedin, Florida. Based on the FEMA zoning this lot is designated as being within both an AE-13 Flood Zone and a VE-14 Flood Zone with the AE zoning being sandwiched between VE zoning to the front and rear of the lot(see FIRM map attached). Test Methods The two SPT borings were done using sampling intervals in excess of those required by ASTM Specifications, D-1586, describing the Standard Penetration Test or "split-spoon" method of sampling. Four samples were taken in the upper ten feet to provide greater definition within this zone. The penetration resistance testing and sample taking was accomplished with the use of a 2" O.D. sampler seated six inches into the bottom of the bore hole and advanced an additional one foot under the effort of a 140 pound hammer falling freely thirty inches. The number of blows required of the hammer to advance the sampler one foot into undisturbed material was noted as the blow count (N) of that particular stratum. Portions of each soil sample so taken, were classified, sealed in moisture-proof containers and returned to our laboratories for verification of field classification. The borings were advanced using a rotary drill rig, utilizing a recirculating bentonite drill fluid to maintain the borehole in noncohesive soils and to remove cuttings created by the drill bit. Upon completion the boreholes were sealed in accordance with SWFWMD regulations. Boring Results The soil profiles identified by the 2 SPT borings are described as follows: Boring B-1 was located in the western portion of the building footprint. This boring identified soils composed of approximately 9 feet of variable density sandy soils that ranged in condition from loose to medium dense. Following these upper sandy soils was firm sandy clays to 20 feet, soft sandy clay/clayey sands to 23 feet and then very stiff to stiff marine clays with weathered limestone fragments from 23 to 33 feet where very hard weathered limestone began and terminated the boring with the 40 feet sampling interval. A loss of drilling fluid circulation occurred at a depth of 29 feet within the stiff clays with limestone fragment formation. Boring B-2, located in the eastern portion of the new building, defined a soil profile composed of approximately 5 feet of slightly loose sands followed by medium dense sands to 11 feet where the firm sandy clay layer began. This layer extended down to a depth of 17 feet where medium hard grading to very hard Central Florida Testing Laboratories, Inc. EB#1066 GB#224

4 Laura and Brian Maiocco Addendum for Proposed Condos Victoria Drive, Dunedin, Fla. CFTL Report No A Page 3 weathered limestone was encountered. The weathered limestone continued to the termination depth of the boring, 30 feet below the surface with two consecutive refusal N values being recorded by its termination depth. No loss of drilling fluid occurred in boring B-2. The shallow groundwater table under this coastal property is influenced by the nearby waters of the Intercoastal Waterway to its west. At the time of our testing it was measured at a depth between 5 and 6 feet beneath the surface. Our recommendation in order to maximize the support capacity for either type piling installed into these soil profiles would be to either drive or drill the piling to a depth that intercepts the underlying, competent limestone formation found at varying but relatively shallow depths ranging between approximately 25 to 35 feet below the surface. The following chart provides safe support capacities for two common types of piling versus depth. Pile Type Size Length Support Treated Timber 8" tip diam tons * 10" tip diam tons * * maximum safe support capacity for this size timber piling. Augercast Concrete 12 diam tons 14 diam tons Lateral load capacities may be expected to be approximately ten percent of the compressive load capacity for individual pile. Uplift may be assumed at approximately 50 percent of the downward axial load capacity. Actual pile support capacities require verification by monitoring of the driving resistance and correlation to the hammer energy at the time of installation, monitoring of auger resistance by drill time or by load testing. We recommend that your Structural Engineer, Architect or Pile Contractor consult with us to determine applicable recommended lengths of pile to order prior to job commencement. Pile lengths depend on the cut-off elevation of the proposed pile above existing grade, the possibility of fill placement on the site prior to pile installation, variations in soil conditions and design support capacities of individual piling. If cut-off elevations are above existing ground and pile design capacities are those shown above for any specific length, we recommend that pile lengths be calculated to place tips up to 35 feet below present land elevations. Fill placement after the installation of the piling will generate drawdown drag on the piling, which can subtract from over-all support capacity Central Florida Testing Laboratories, Inc. EB#1066 GB#224

5 Laura and Brian Maiocco Addendum for Proposed Condos Victoria Drive, Dunedin, Fla. CFTL Report No A Page 4 of the piling. Therefore, if any fill is to be placed on the lot to raise its overall elevation, we recommend it be placed prior to pile installation if at all possible and under engineered earthwork specifications which are: For any fill is to be placed within the new building envelope, we recommend it consist of clean, noncohesive sandy soils meeting either SP or SP/SM classification by the Unified Soil Classification System. Fill should be placed in lifts not exceeding one foot in depth and compacted to a minimum density of at least ninety-five percent (95%) of the soils maximum dry density as established by the Modified Proctor Test, ASTM D Each lift should achieve satisfactory density results prior to placement and compaction of subsequent lifts to eliminate the possibility of dense soil bridging over loose insufficiently compacted soils. Our office is available to conduct any recommended compaction testing of soils, monitoring of either driven or augercast piling installation programs, and testing of any structural concrete used during construction of the project. Limitations Our initial geotechnical report contained limitations regarding our soils investigation and the report. Other than additional information provided in the recommendations of this addendum, all previous findings, recommendations and limitations still pertain to this report. We appreciate the opportunity to have been of service. If any further evaluation of the site or testing services are needed, either prior to or during construction, please do not hesitate to contact our office. Sincerely, CENTRAL FLORIDA TESTING LABORATORIES, INC. George C. Sinn, Jr., P.E. FLN President/Principal Engineer GCS/gs Attachments Not for public use unless original signature, date and raised seal are applied. Central Florida Testing Laboratories, Inc. EB#1066 GB#224

6 Project Name: Proposed Condos / 1129 Victoria Drive, Dunedin Report No.: A Maps Various Central Florida Testing Laboratories, Inc. EB#1066 GB#224

7 Central Florida Testing Laboratories, Inc. Legend Figure 1 - Location PROPOSED CONDOS 1129 Victoria Drive Dunedin, Florida Report No: A Subject Property Population Center Land Sand Woodlands Park Interstate Toll Highway US Highway State Route Local Road Major Connector Water Intermittent Lake Wetland River/Canal Intermittent River Railroad

8 Project Name: Proposed Condos / 1129 Victoria Drive, Dunedin Report No.: A 2016 Aerial Photograph of Site Central Florida Testing Laboratories, Inc. EB#1066 GB#224

9 Project Name: Proposed Condos / 1129 Victoria Drive, Dunedin Report No.: A 2016 Aerial Photograph of Site Central Florida Testing Laboratories, Inc. EB#1066 GB#224

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11 Proposed Condos Victoria Drive Approximate Test Locations Report No A ; B-1 ; B-2

12 Project Name: Proposed Condos / 1129 Victoria Drive, Dunedin Report No.: A SPT Boring Results Central Florida Testing Laboratories, Inc. EB#1066 GB#224

13 Client: Laura and Brian Maiocco Project: Proposed Condos Location: 1129 Victoria Drive City / State: Dunedin, Florida Report No: A Log of Borehole: B-1 Date Drilled: 04/11/2017 ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO Depth Strata Symbol Ground Surface Sand Light gray, fine grained Sand White, fine grained Subsurface Profile Description Consistency slightly loose loose Blow Count N value 9 6 Standard Penetration Test (blows/ft) Lab/ Notes 5 Sand Brown, fine grained slightly loose medium dense firm PI = Sandy Clay Greenish gray firm Clayey Sand Light greenish gray, fine grained soft very stiff Clay Greenish gray, with weathered limestone stiff % LOC 35 Limestone White, weathered very hard 50/3" very hard /5" 100+ End of Boring 45 Notes: FEMA Flood Zones: AE-13 and VE-14 PI = Plasticity Index Drill Method: Rotary Sampling Method: Splitspoon ASTM D % loss of circulation at 29.0' bls Installed 20' PVC casing Borehole plugged and grouted Water Table: 5.5' bls (HA) Ground Elevation: Existing Drilled by: AC/JS Compiled by: PG Sheet 1 of 1

14 Client: Laura and Brian Maiocco Project: Proposed Condos Location: 1129 Victoria Drive City / State: Dunedin, Florida Report No: A Log of Borehole: B-2 Date Drilled: 04/11/2017 ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO Depth Strata Symbol Ground Surface Subsurface Profile Description Consistency Blow Count N value Standard Penetration Test (blows/ft) Lab/ Notes Sand White, fine grained slightly loose slightly loose Sand Brown, fine grained slightly loose medium dense Sand Dark brown, fine grained firm Sandy Clay Light greenish gray and greenish gray firm Clay Greenish gray, with weathered limestone fragments 20 Limestone White, weathered, with calcareous clay medium hard very hard 50/1" 100+ Limestone White, weathered 30 very hard 13-50/4" 100+ End of Boring Notes: FEMA Flood Zones: AE-13 and VE-14 Drill Method: Rotary Sampling Method: Splitspoon ASTM D-1586 No loss of drill fluid circulation Borehole plugged and grouted Water Table: 5.5' bls (HA) Ground Elevation: Existing Drilled by: AC/JS Compiled by: PG Sheet 1 of 1