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HomeMy WebLinkAboutGATEWAY AT HARMONY ROAD PUD, 3RD FILING, LOTS 1 & 2, M & O TIRE AUTOMOTIVE - PRELIMINARY & FINAL - 1-88G - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORT GEOTECHNICAL ENGINEERING REPORT PROPOSED M&O TIRE STORE AND MCDONALD'S PARKING LOT MASON STREET AND KENSINGTON DRIVE FORT COLLINS, COLORADO ELI PROJECT NO. 20955069 April 21, 1995 I t I I I �P�o R A � CCN _ a N A Division of The Terracon Companies, Inc. GEOTECHNICAL ENGINEERING REPORT PROPOSED M&0 TIRE STORE AND MCDONALD'S PARKING LOT MASON STREET AND KENSINGTON DRIVE FORT COLLINS, COLORADO ELI PROJECT NO. 20955069 April 21, 1995 Prepared for: MR. PAUL HEFFRON 750 17TH STREET BOULDER, CO 80302 — AND MARTIN RESTAURANTS, INC. 2912 WEST 10TH STREET _ GREELEY, CO 80031 Prepared by: Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. 301 North Howes Fort Collins, CO 80521 Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. 60R47.0 Empire Laboratories, Inc. 444 A Division of The Terracon Companies, Inc. CC cn P.O. Box 503•301 No. Howes = Fort Collins,Colorado 80522 n (303)484-0359 Fax(303)484-0454 April 21, 1995 Chester C.Smith,P.E. Larry G.O'Dell,P.E. Neil R.Sherrod,C.P.G. Mr. Paul Heffron 750 17th Street - — Boulder, CO 80302 Martin Restaurants, Inc. - _ 2912 West 10th Street Greeley, CO 80031 Attn: Mr. Ernie Martin Re: Geotechnical Engineering Report, Proposed M&O Tire Store _ and McDonald's Parking Lot, Mason Street and Kensington Drive Fort Collins, Colorado •= ELI Project No. 20955069., Empire Laboratories, Inc. (ELI) has completed a geotechnical engineering exploration for the proposed M&O Tire Store and the addition to McDonald's restaurant parking lot in the southeast corner of Mason Street and Kensington Drive. This study was performed in general accordance with our proposal number 2095120 dated April 19, 1995. The results of our engineering study, including the boring location diagram, laboratory test results, test boring records, and the geotechnical recommendations needed to aid in the design and construction of foundations and other earth connected phases of this project are attached. The subsurface soils at the site consist of sandy lean clay with gravel underlain by silty sand with gravel. The information obtained by the results of field exploration and laboratory - — testing indicates the clay soils exhibits low to moderate swell potential and moderate bearing characteristics. The granular soils are not expansive and exhibit moderate bearing characteristics. Based on the geotechnical engineering analysis, subsurface exploration and laboratory test results, we recommend the proposed tire store be supported on a spread footing and/or grade beam foundation system. Slab-on-grade may be utilized for the interior floor system provided that care is taken in the placement and compaction of the subgrade soil. If no movement can be tolerated, consideration should be given to use of a structural floor system. Other design and construction details, based upon geotechnical conditions, are presented in the report. Offices of The Terracon Companies,Inc. Geotechnical,Environmental and Materials Engineers Arizona ■ Arkansas IN Colorado ■ Idaho ■ Illinois IS Iowa ■ Kansas ■ Minnesota Missouri • Montana IN Nebraska ■ Nevada ■ Oklahoma • Texas ■ Utah ■ Wyoming i i Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955069 __ We appreciated being of service in the geotechnical engineering phase of this project, and are prepared to assist during the construction phases as well. If you have any questions concerning this report or any of our testing, inspection, design and consulting services, please do not hesitate to contact us. j > ...T PRofF" Sincerely, - v' .•F•,Zilf Zi • r;',( i EMPIRE LABORATORIES, INC. �'`�� 2575 Fa""•` I y C.i 1✓ A Division of The Terracon Companies, Inc. W : AIPG N • r ,:„., 9 Fj R. SHtiP$�`- rROFESSIC Neil R. Sherr d 1 Senior Engineering Geologist JReviewed by: oolii.ln11,, _ `:,`��o1Ar a Re,,,'% cjui 6, (9 tots..(1 Ls, . ,...,,,, ..y2,1 G. 67.. .".„s ...,;.. Larry G. O'Dell, P.E. _ 22750 •S __ Office Manager s o • F ' '��d, . .• c4. — NRS/LGO/dmf ii /8111111110‘ Copies to: Addressee (1) _ Ripley & Associates (2) Martin Restaurants (1) iii . 1 Exploration Geotechnical Engineering Ex p Paul Heffron/Martin Restaurants -- ELI Project No. 20955059 — TABLE OF CONTENTS u Page No. Letter of Transmittal ii u s INTRODUCTION 1 PROPOSED CONSTRUCTION 1 . SITE EXPLORATION 2 Field Exploration 2 •• Laboratory Testing 2 SITE CONDITIONS 3 • SUBSURFACE CONDITIONS 3 Geology 3 Soil and Bedrock Conditions 4 Field and Laboratory Test Results 4 Groundwater Conditions 4 CONCLUSIONS AND RECOMMENDATIONS 5 Geotechnical Considerations 5 Foundation Systems 5 Lateral Earth Pressures 6 Seismic Considerations 7 Floor Slab Design and Construction 7 Earthwork 10 — Site Clearing and Preparation 10 Excavation 10 Slab Subgrade Preparation 11 — Pavement Subgrade Preparation ' 11 Fill Materials 11 u i Placement and Compaction 12 ____ Slopes 1313 Compliance 13 Excavation and Trench Construction 14 Drainage Surface Drainage 14 14 .. Exterior Slab Design and Construction 15 Underground Utility Systems 15 Corrosion Protection u s GENERAL COMMENTS 16 mu 1 a Geotechnical Engineering Exploration Paul Heffron/Martin Restaurants ELI Project No. 20955059 TABLE OF CONTENTS (Cont'd) • APPENDIX A Site Plan Figure No. 1 Logs of Borings Al thru A5 APPENDIX B Swell-Consolidation Test B1 Summary of Test Results B2 thru B3 40 APPENDIX C: GENERAL NOTES Drilling & Exploration Cl Unified Soil Classification C2 Laboratory Testing, Significance and Purpose C3 Report Terminology C4 APPENDIX D Recommended Preventative Maintenance-Asphalt Concrete Pavements . . . . D1 Recommended Preventative Maintenance-Jointed Concrete Pavements . . . . D2 . d k 4 Terracon s ` GEOTECHNICAL ENGINEERING REPORT PROPOSED M&O TIRE STORE AND MCDONALD'S PARKING LOT MASON STREET AND KENSINGTON DRIVE FORT COLLINS, COLORADO ELI Project No. 20955069 April 21, 1995 Liz Lao INTRODUCTION _. This report contains the results of our geotechnical engineering exploration for the proposed M&O Tires store and the addition to the McDonald's restaurant parking lot located at the La: southeast corner of Mason Street and Kensington Drive in south Fort Collins, Colorado. The site is located in the SEA of Section 35, Township 7 North, Range 69 West of the 6th L as Principal Meridian. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: -- • subsurface soil conditions • groundwater conditions • foundation design and construction La • lateral earth pressures • floor slab design and construction • pavement design and construction • earthwork • drainage Ii The conclusions and recommendations contained in this report are based upon the results of field and laboratory testing, engineering analysis, our experience with similar soil a conditions and structures and our understanding of the proposed project. PROPOSED CONSTRUCTION It is our understanding the proposed construction is to consist of a single-story, slab-on- grade tire store with associated parking as well as an additional parking lot for the McDonald's restaurant to the south. A small detention pond maximum 2% feet deep is to be constructed within the parking lot area. Wall and column loads are assumed to be approximately 3 kips per lineal foot and 30 kips, respectively. I--. L y Geotechnical Engineering Exploration Terracon L Paul Heffron/Martin Restaurants ELI Project No. 20955059 L' , rSITE EXPLORATION The scope of the services performed for this project included site reconnaissance by an engineering geologist, a subsurface exploration program, laboratory testing and engineering L_ analysis. Field Exploration: A total of five (5) test borings were drilled on April 19, 1995 to depths L - of 10 to 15 feet at the locations shown on the Site Plan, Figure 1 . Three borings were I drilled within the footprint of the proposed building, and two borings were drilled in the area �+ of proposed pavements. All borings were advanced with a truck-mounted drilling rig, utilizing 4-inch diameter solid stem auger. L.; The borings were located in the field by pacing from existing street intersections. Elevations were taken at each boring location by measurements with an engineer's level L from a temporary bench mark (TBM) shown on the Site Plan. The accuracy of boring locations and elevations should only be assumed to the level implied by the methods used. L.; Continuous lithologic logs of each boring were recorded by the geotechnical engineer during the drilling operations. At selected intervals, samples of the subsurface materials were L---- taken by pushing thin-walled Shelby tubes, or by driving split-spoon samplers. Penetration resistance measurements were obtained by driving the split-spoon into the L subsurface materials with a 140-pound hammer falling 30 inches. The penetration resistance value is a useful index to the consistency, relative density or hardness of the _ materials encountered. L Groundwater was checked at the time of exploration and one day after drilling. L--; Laboratory Testing: All samples retrieved during the field exploration were returned to the laboratory for observation by the project geotechnical engineer, and were classified in accordance with the Unified Soil Classification System described in Appendix C. At that time, the field descriptions were confirmed or modified as necessary and an applicable laboratory testing program was formulated to determine engineering properties of the L.- subsurface materials. Boring logs were prepared and are presented in Appendix A. Li L2 1 ' L_ Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants L�- ELI Project No. 20955059 Selected soil samples were tested for the following engineering properties: • Water content • Expansion • Dry density • Plasticity Index • Consolidation • Water soluble sulfate content • Compressive strength The significance and purpose of each laboratory test is described in Appendix C. Laboratory test results are presented in Appendix B, and were used for the geotechnical engineering L analyses, and the development of foundation and earthwork recommendations. All laboratory tests were performed in general accordance with the applicable ASTM, local or other accepted standards. -. SITE CONDITIONS The site is a vacant tract of land sparsely vegetated with grass. The area is relatively flat �. and has minor drainage to the south. Water was ponded in the southeast corner of the site at the time of the site exploration. The property is bordered to the north by Kensington Drive, to the west by Mason Street, to the east by a paved entrance to Jiffy Lube and to the south by a paved entrance to the McDonald's restaurant. SUBSURFACE CONDITIONS Geology: The proposed area is located within the Colorado Piedmont section of the Great Plains physiographic province. The Colorado Piedmont, formed during Late Tertiary and Early Quaternary time (approximately 2,000,000 years ago), is a broad, erosional trench which separates the Southern Rocky Mountains from the High Plains. Structurally, the site lies along the western flank of the Denver Basin. During the Late Mesozoic and Early Cenozoic Periods (approximately 70,000,000 years ago),intense tectonic activity occurred, causing the uplifting of the Front Range and associated downwarping of the Denver Basin to the east. Relatively flat uplands and broad valleys characterize the present-day topography of the Colorado Piedmont in this region. The site is underlain by Cretaceous Pierre Formation. It is estimated that the bedrock underlies the site at depths of 20 to 25 feet. The Pierre shale is overlain by residual and/or alluvial gravels and clays of Pleistocene and/or Recent Age. . 3 L� C Geotechnical Engineering Exploration Terracon ` Paul Heffron/Martin Restaurants t— ELI Project No. 20955059 L.: Mapping completed by the Colorado Geological Survey ('Hart, 1972), indicates the site in an area of "Moderate Swell Potential". Potentially expansive materials mapped in this area L include bedrock, weathered bedrock and colluvium (surficial units). Soil and Bedrock Conditions: The following describes the characteristics of the primary soil L_ strata [in order of increasing depths]: L • Fill Material: One to two foot layer of fill material was encountered at the surface of the five borings drilled at the site. The fill consists of sandy lean clay. The clay L i is moist and stiff in consistency. _ • Sandy Lean Clay with Gravel: This stratum underlies the fill and extends to depths LE of 121/2 to 14 feet below=the surface. The sandy lean clay is moist, stiff to very stiff. • Silty Sand with Gravel. This stratum was encountered below the upper clays in LT borings 1 through 3 and extends beyond the depths explored. The gravel is dry to moist and medium dense to dense in consistency. t _ Field and Laboratory Test Results: Field and laboratory test results indicate that the clay soils exhibit low to moderate swell potential and moderate bearing characteristics. The granular soils are non-expansive and exhibit moderate bearing characteristics. i .... Groundwater Conditions: Groundwater was not observed in any test boring at the time of field exploration, nor when checked one day after drilling. These observations represent L. only current groundwater conditions, and may not be indicative of other times, or at other locations. Groundwater levels can be expected to fluctuate with varying seasonal and i .• weather conditions. Based upon review of U.S. Geological Survey maps (2Hillier, et al, 1983), regional j groundwater is expected to be encountered in unconsolidated alluvial deposits on the site, at depths ranging from 10 to 20 feet below the existing ground surface at the project site. L. 'Hart, Stephen S., 1972, Potentially Swelling Soil and Rock in the Front Range Urban Corridor, Colorado, Colorado ra Geological Survey, Environmental Geology No. 7. 2Hillier, Donald E.;Schneider,Paul A.,Jr.;and Hutchinson,E.Carter, 1983,Depth to Water Table(1979)in the Boulder-Fort Collins-Greeley Area, Front Range Urban Corridor, Colorado, United States Geological Survey, Map 1-855-I. 4 L_ Geotechnical Engineering Exploration Terracon L_ Paul Heffron/Martin Restaurants ELI Project No. 20955059 L� CONCLUSIONS AND RECOMMENDATIONS Geotechnical Considerations: The site appears suitable for the proposed construction. Potentially expansive soils will require particular attention in the design and construction. The following foundation systems were evaluated for use on the site: • spread footings and/or grade beams bearing on undisturbed soils; and, • spread footings and/or grade beams bearing on engineered fill. Slab-on-grade construction is considered acceptable for use provided that design and construction recommendations •,are followed. If no movement can be tolerated, —_ considerations should be given to use of a structural floor system. Foundation Systems: Due to the presence of low to moderate swelling soils on the site, spread footing and/or grade beam foundations bearing upon undisturbed subsoils are .e recommended for support for the proposed structure. The footings may be designed for a _ maximum bearing pressure of 2,500 psf. In addition, the footings should be sized to maintain a minimum dead-load pressure of 750 psf (dead load plus 1 live load). The design ® bearing pressure may be increased by one-third when considering total loads that include wind or seismic conditions. In order to maintain the minimum dead-load pressure, it may be necessary to design and construct a system of grade beams and isolated footing pads. To maintain the minimum dead-load pressure on footings, a minimum 4-inch void space should be provided beneath the grade beams between footing pads (if utilized). Existing fill on the site should not be used for support of foundations without removal and recompaction. Any additional fill should be placed prior to foundation construction to allow for some consolidation of the subsoils from the added weight of the new fill. Exterior footings should be placed a minimum of 30 inches below finished grade for frost protection. Finished grade is the lowest adjacent grade for perimeter footings. Footings should be proportioned to minimize differential foundation movement. Proportioning on the basis of equal total settlement is recommended; however, proportioning to relative constant dead-load pressure will also reduce differential settlement W 5 V L. LI L: Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 Li_-, between adjacent footings. Total or differential settlement resulting from the assumed L. structural loads are estimated to be on the order of 3/4 inch or less. Additional foundation movements could occur if water from any source infiltrates the foundation soils; therefore, proper drainage should be provided in the final design and during construction. L. Footings, foundations, and masonry walls should be reinforced as necessary to reduce the potential for distress caused by differential foundation movement. The use of joints at LI.: openings or other discontinuities in masonry walls is recommended. r Foundation excavations should be observed by the geotechnical engineer. If the soil conditions encountered differ from those presented in this report, supplemental recommendations will be required. Li:: Lateral Earth Pressures: For soils above any free water surface, recommended equivalent fluid pressures for unrestrained foundation elements are: L. • Active: Clay 40 psf/ft LI • Passive: 1:- Clay 360 psf/ft • Adhesion at base of footing 500 psf Where the design includes restrained elements, the following equivalent fluid pressures are L. recommended: • At rest: L. Clay 60 psf/ft The lateral earth pressures herein are not applicable for submerged soils. Additional recommendations may be necessary if such conditions are to be included in the design. L., L._ Fill against grade beams and retaining walls should be compacted to densities specified in "Earthwork". Compaction of each lift adjacent to walls should be accomplished with hand- operated tampers or other lightweight compactors. Overcompaction may cause excessive L....1_ lateral earth pressures which could result in wall movement. L. 6 L_- L" Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 Seismic Considerations: The project site is located in Seismic Risk Zone I of the Seismic Zone Map of the United States as indicated by the Uniform Building Code. Based upon the nature of the subsurface materials, a seismic site coefficient, "s" of 1.0 should be used for the design of structures for the proposed project (Uniform Building Code, Table No. 23-J). Floor Slab Design and Construction: Low to moderate expansive soils or engineered fill will support the floor slab. Some differential movement of a slab-on-grade floor system is possible should the subgrade soils become elevated in moisture content. Such movements — are considered within general tolerance for normal slab-on-grade construction. To reduce any potential slab movements, the subgrade soils should be prepared as outlined in the "Earthwork" section of this report. If no movement can be tolerated, consideration should be given to use of a structural floor system. For structural design of concrete slabs-on.-grade, a modulus of subgrade reaction to 100 pounds per cubic inch (pci) may be used for floors supported on existing or engineered fill consisting of on-site soils. Additional floor slab design and construction recommendations are as follows: • Positive separations and/or isolation joints should be provided between slabs and all foundations, columns or utility lines to allow independent movement. • Contraction joints should be provided in slabs to control the location and extent of cracking. Maximum joint spacing of 15 to 20 feet in each direction is recommended. • Interior trench backfill paced beneath slabs should be compacted in accordance with recommended specifications outlined below. • In areas subjected to normal loading, a minimum 4-inch layer of clean-graded gravel be placed beneath interior slabs. For heavy loading, a minimum 6-inch layer of aggregate base course should be placed beneath interior slabs. • If moisture sensitive floor coverings are used on interior slabs, consideration should be given to the use of barriers to minimize potential vapor rise through the slab. • Floor slabs should not be constructed on frozen subgrade. 7 i j L r Geotechnical Engineering Exploration Terracon L--- Paul Heffron/Martin Restaurants ELI Project No. 20955059 L__ • Other design and construction considerations, as outlined in the ACI Design L.-- Manual, Section 302.1R are recommended. The required total thickness for the pavement structure is dependent primarily upon the foundation soil or subgrade and upon traffic conditions. Based on the soil conditions Lencountered at the site, the type and volume of traffic and using a group index of 9 as the criterion for pavement design, the following minimum pavement thicknesses are L-- recommended: Recommended alternatives for flexible and rigid pavements, summarized for each traffic Larea, are as follows: i u Recommended Pavement Section Thickness (inches) Alter Plant Mixed Portland Traffic Area native Asphalt Aggregate _ Base Course Concrete Bituminous Cement Total Surface Base Concrete L A 3 4 7 I Automobile B 2 21/2 4'/2 L Parking C 5 .. A 3 g 11 Main Traffic B 2 4 6 Corridors C 6 rEach alternative should be investigated with respect to current material availability and E_____: economic conditions. Aggregate base course (if used on the site) should consist of a blend of sand and gravel L. which meets strict specifications for quality and gradation. Use of materials meeting Colorado Department of Transportation Class 5 or 6 specifications is recommended for base [ ,..: course. Aggregate base course should be compacted to a minimum of 95% Standard Proctor 1 — Density (ASTM D698). Asphalt concrete should be obtained from an approved mix design stating the Hveem L-t properties, optimum asphalt content,job mix formula, and recommended mixing and placing temperatures. Aggregate used in asphalt concrete should meet a particular gradation. Use V8 I► -' L__ LI Geotechnical Engineering Exploration Terracon L.: Paul Heffron/Martin Restaurants ELI Project No. 20955059 LIof materials meeting Colorado Department of Transportation Grading C or CX specification is recommended. The mix design should be submitted prior to construction to verify its L ' adequacy. The asphalt materials should be placed in maximum 3-inch lifts, and should be compacted to a minimum of 95% or Hveem density (ASTM D1560). L__ Plant-mixed bituminous base course should be composed of a mixture of aggregate, filler and additives if required, and approved bituminous material. The bituminous base should L .:.: conform to an approved mix design stating the Hveem properties, optimum asphalt content, job mix formula, and recommended mixing and placing temperatures. Aggregate used in L___y plant-mixed bituminous base course should meet a particular gradation. Use of aggregates meeting Colorado Department of Transportation Grading G or C specifications is recommended. The mix design should be submitted prior to construction to verify it adequacy. The asphalt material should be placed in maximum 3-inch lifts, and should be Lcompacted to a minimum of 95% Hveem_density (ASTM D1560). Li: Where rigid pavements are used, the concrete should be obtained from an approved mix design with the following minimum properties: • Modulus of Rupture @ 28 days 650 psi minimum L.: • Strength Requirements ASTM C94 Lia • Minimum Cement Content 6.5 sacks/cu. yd. • Cement Type Type I Portland • Entrained Air Content 6 to 8% Lin • Concrete Aggregate ASTM C33 and CDOT Section 703 • Aggregate Size 1 inch maximum • Maximum Water Content 0.49 lb/lb of cement L ...1 • Maximum Allowable Slump 4 inches -.: Concrete should be deposited by truck mixers or agitators and placed a maximum of 90 minutes from time the water is added to the mix. Other specifications outlined by the Colorado Department of Transportation should be followed. LT_ Longitudinal and transverse joints should be provided as needed in concrete pavements for expansion/contraction and isolation. The location and extent of joints should be based upon the final pavement geometry and should be placed (in feet), at roughly twice the slab thickness (in inches), on center in either direction. Sawed joints should be cut within 24- - hours of concrete placement, and should be a minimum of 25% of slab thickness plus 1/4 ___ inch. All joints should be sealed to prevent entry of foreign material and dowelled where 9 L_ Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 necessary for load transfer. Where dowels cannot be used at joints accessible to wheel loads, pavement thickness should be increased by 25 percent at the joints and tapered to regular thickness in 5 feet. Earthwork: • Site Clearing and Preparation: 1. Strip and remove existing vegetation, debris, and other deleterious materials from proposed building and pavement areas. All exposed surfaces should be free of mounds and depressions which could prevent uniform compaction. 2. If unexpected fills or underground facilities are encountered during site clearing, such features should be removed and the excavation thoroughly cleaned prior to backfill placement and/or construction. All excavations L . should be observed by the geotechnical engineer prior to backfill placement. 3. Stripped materials consisting of vegetation and organic materials should be wasted from the site, or used to revegetate exposed slopes after completion of grading operations. If it is necessary to dispose of organic materials on- site, they should be placed in non-structural areas, and in fill sections not exceeding 5 feet in height. 4. The site should be initially graded to create a relatively level surface to receive fill, and to provide for a relatively uniform thickness of fill beneath proposed building structures. 5. All exposed areas which will receive fill, once properly cleared and benched where necessary, should be scarified to a minimum depth of 8 inches, conditioned to near optimum moisture content, and compacted. • Excavation: 1 . It is anticipated that excavations for the proposed construction can be accomplished with conventional earthmoving equipment. 10 Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 • Slab Subgrade Preparation: Subgrades below slabs-on-grade should be scarified and recompacted to the required moisture and density. • Pavement Subgrade Preparation: 1. The subgrade should be scarified, moistened as required, and recompacted -- for a minimum depth of 8 inches prior to placement of fill and pavement materials. 2. On-site clay soils may pump or become unstable or unworkable at high water contents. Workability may be improved by scarifying and drying. Overexcavation of wet zones and replacement with granular materials may be necessary. Lightweight excavation equipment may be required to reduce subgrade pumping. Use of lime, fly ash, kiln dust, cement or geotextiles could also be considered as a stabilization technique. Laboratory evaluation is recommended to determine the effect of chemical stabilization on subgrade soils prior to construction. Proof-rolling of the subgrade may be required to determine stability prior to paving. • Fill Materials: 1 . Clean on-site soils or approved imported materials may be used as fill material for the following: • general site grading • exterior slab areas • foundation areas • pavement areas • interior floor slab areas • foundation backfill �- 2. Frozen soils should not be used as fill or backfill. 3. Imported soils (if required) should conform to the following: 11 L_. Ln Geotechnical Engineering Exploration Terracon L_ Paul Heffron/Martin Restaurants jELI Project No. 20955059 Percent fines by weight Gradation (ASTM C136) L., 100 3" L 70-100 No. 4 Sieve 50-80 No. 200 Sieve 65 (max) L • Liquid Limit 35 (max) • Plasticity Index 20 (max) Li_ • Placement and Compaction: ' 1 . Place and compact-fill in horizontal lifts, using equipment and procedures that L! will produce recommended moisture contents and densities throughout the lift. L2. No fill should be placed over frozen ground. 3. Materials should be compacted to the following: LMinimum Percent L - Material (ASTM D698) Subgrade soils beneath fill areas 95 L On-site soils or approved imported fill: Beneath foundations 98 Beneath slabs 95 L Beneath pavements 95 Aggregate base (beneath slabs) 95 LMiscellaneous backfill 90 L 4. If a well defined maximum density curve cannot be generated by impact compaction in the laboratory for any fill type, engineered fill should be L, compacted to a minimum of 80 percent relative density by determined by ASTM D4253 D4254. 5. On-site clays should be compacted within a moisture content range of LI, optimum moisture to 2 percent above optimum moisture below building L 2 1 A 1 — L Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 areas. On-site clays below paved areas and imported granular soils should be compacted within a moisture range of -2 percent below to 2 percent above optimum. �J • Slopes: 1 . For permanent slopes in compacted fill areas, recommended maximum slope angles of 2 Y :1 (horizontal to vertical) for on-site materials are recommended. Lr 2. For permanent slopes in cut areas, the following maximum angles are recommended as fbilows: �— Slope e S p Material Horizontal:Vertical Clays 3:1 Detention Basin Slopes 3:1 • Compliance: Performance of slabs-on-grade, foundations and pavement elements supported on compacted fills or prepared subgrade depend upon compliance with "Earthwork" recommendations. To assess compliance, observation and testing should be performed under the direction of the geotechnical engineer. 1 • Excavation and Trench Construction: Excavations into the on-site soils will encounter a variety of conditions. Excavations into the clays can be expected to stand on relatively steep temporary slopes during construction. However,the granular soils may cave and groundwater may be encountered. The individual _ contractor(s) should be made responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom. All excavations should be sloped or shored in the interest of safety following local, and federal regulations, including current OSHA excavation and trench safety standards. 13 Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 — If any excavation, including a utility trench, is extended to a depth of more than 20 feet, it will be necessary to have the side slopes designed by a professional engineer. The soils to be penetrated by the proposed excavations may vary significantly across the site. The preliminary soil classifications are based solely on the _ materials encountered in widely spaced exploratory test borings. The contractor should verify that similar conditions exist throughout the proposed area of excavation. If different subsurface conditions are encountered at the time of construction, the actual conditions should be evaluated to determine any excavation modifications necessary to maintain safe conditions. As a safety measure, it is recommended that all vehicles and soil piles be kept to a minimum lateral distance from-the crest of the slope equal to no less than _ the slope height. The exposed slope face should be protected against the elements. Drainage: • Surface Drainage: 1 . Positive drainage should be provided during construction and maintained throughout the life of the proposed building and parking lot. Infiltration of water into utility or foundation excavations must be prevented during construction. Planters and other surface features which could retain water in areas adjacent to the building or pavements should be sealed or eliminated. 2. In areas where sidewalks or paving do not immediately adjoin the structure, we recommend that protective slopes be provided with a minimum grade of approximately 10 percent for at least 10 feet from perimeter walls. Backfill against footings, exterior walls, and in utility and sprinkler line trenches should be well compacted and free of all construction debris to reduce the possibility of moisture infiltration. 14 l.— Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 3. Downspouts, roof drains or scuppers should discharge into splash blocks or extensions when the ground surface beneath such features is not protected by exterior slabs or paving. = 4. Sprinkler systems should not be installed within 5 feet of foundation L walls. Landscaped irrigation adjacent to the foundation system should be minimized or eliminated. L _ • Exterior Slab Design and Construction: Exterior slabs-on-grade, exterior architectural features, and utilities founded on, or in backfill may experience some movement due to the volume change of the backfill. Potential movement could be reduced by: • minimizing moisture increases in the backfill �— • controlling moisture-density during placement of backfill • using designs which allow vertical movement between the exterior features and adjoining structural elements • placing effective control joints on relatively close centers • allowing vertical movements in utility connections • Underground Utility Systems: All piping should be adequately bedded for proper load distribution. It is suggested that clean, graded gravel compacted to 80 i percent of Relative Density ASTM D4253 be used as bedding below the pipe. L Where utilities are excavated below groundwater, temporary dewatering will be required during excavation, pipe placement and backfilling operations for proper construction. Utility trenches should be excavated on safe and stable slopes in accordance with OSHA regulations as discussed above. Backfill should consist of the on-site soils or approved imported material. The pipe backfill should be compacted to a minimum of 95 percent of Standard Proctor Density ASTM D698. L • Corrosion Protection: Results of soluble sulfate testing indicate that ASTM Type I-II Portland cement is suitable for all concrete on and below grade. Foundation concrete should be designed in accordance with the provisions of the ACI Design Manual, Section 318, Chapter 4. I — 15 �y= Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 L_ GENERAL COMMENTS It is recommended that the Geotechnical Engineer be retained to provide a general review of final design plans and specifications in order to confirm that grading and foundation recommendations have been interpreted and implemented. In the event that any changes of the proposed project are planned, the conclusions and recommendations contained in this report should be reviewed and the report modified or supplemented as necessary. The Geotechnical Engineer should also be retained to provide services during Lexcavation, grading, foundation and construction phases of the work. Observation of footing excavations should be performed prior to placement of reinforcing and concrete I - to confirm that satisfactory bearing materials are present and is considered a necessary part of continuing geotechnical engineering services for the project. Construction testing, including field and laboratory evaluation of fill, backfill, pavement materials, concrete and steel should be performed to determine whether applicable project requirements have been met. It would be logical for Empire Laboratories, Inc. to _ provide these additional services for continuing from design through construction and to determine the consistency of field conditions with those data used in our analyses. The analyses and recommendations in this report are based in part upon data obtained from the field exploration. The nature and extent of variations beyond the location of test borings may not become evident until construction. If variations then appear evident, it may be necessary to re-evaluate the recommendations of this report. L_ f _ Our professional services were performed using that degree of care and skill ordinarily exercised, under similar circumstances, by reputable geotechnical engineers practicing in this or similar localities. No warranty, express or implied, is made. We prepared the report as an aid in design of the proposed project. This report is not a bidding document. Any contractor reviewing this report must draw his own conclusions regarding site conditions and specific construction techniques to be used on this project. 16 Geotechnical Engineering Exploration Terracon Paul Heffron/Martin Restaurants ELI Project No. 20955059 This report is for the exclusive purpose of providing geotechnical engineering and/or testing information and recommendations. The scope of services for this project does not include, either specifically or by implication, any environmental assessment of the site or identification of contaminated or hazardous materials or conditions. If the owner is concerned about the potential for such contamination, other studies should be undertaken. 17 T.B.M. - NORTH jl 0-- RIM OF MANHOLE ELEVATION = 100.0 KENSINGTON DRIVE l io ' ® MI o r u No.1 , 5,,,,,,././,,, /ice///// 7/ 1 ii. 11 M & O TIRES a'N , � ./A - No.2 I No.3 /,7 - i 0 6 No.4 ,glfl • 1 .w DETENTION POND ILI 1 IllCC J .., , _ fn . 1, ,, _ . ,.. , co i. 1 ® No.5 III \\1: --. t --. , .../ ,.. } E -9 i . . i ® ® ® 111=IIMEENNEMI ® ® InEntiMaganiall ® ® ram.-. _ .__It- 'I I Iii I FIGS R I-I 1 : SITH PLAN or III \ , MASON STREET & KENSINGTON DRIVE j FORT COLLINS, COLORADO j — 1; ELI. PROJECT No. 20955069 SCALE 1" = 40' 1IIII — 11 ____ Empire Laboratories, Inc. __ 1! A Division of The Terracon Companies, Inc.