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HomeMy WebLinkAboutGeotechnical Exploration ". ~- TABLE OF CONTENTS Page No. PROJECT I NFORMA TION.... ..... ... I' ..... II... II ... II ....... ........1...1.. ...... ..... .... ... .................. .....1 . Project Authorization ............................................................... .... ............ 1 . Project Oescri ption .... ....... ... I' ..... ...... II ........ ..... ..... .......... ....... 1..1......... .....1 . Purpose and Scope of Services..............................................................2 SITE AND SU BSURF ACE CONDITIONS....................................................................... 3 . Site Location and Description.................................................................3 . Site Geology .. I. .....1.. ....... I... II ...... ...... ..... ..... ........ ..... ....... .... ....... .......... ..... 3 . Subsurface Conditions......1 ....... II .... ........... ...... ........ ..... .... ...... .........1. 1....3 . Groundwater Information . ...... ..... ............................ .... ............... .............5 EVALUATION AND RECOMMENDATIONS ..................................................................6 . Geotechnical Discussion .......... ................. ..............................................6 . Site Preparation .... ............... .... ...... .................................. .........................6 . Foundation Recommendations........................................................ .......8 . Seismic Design Considerations .......... .................. ........ .......... ................ 9 . Floor Slab Recommendations ...............................................................1 0 . General Pavement Recommendations .................................................11 . Pavement Subgrade Preparation ..........................................................13 . Pavement Drainage & Maintenance ......................................................13 CONSTRUCTION CONSiDERATIONS......................................................... ................14 . Moisture Sensitive SoilslWeather Related Concerns .........................14 . Drainage and Groundwater Considerations ........................................15 . Excavations ...... ...................................................... ................................15 GEOTE CHNICAL RiSK............... ....... ........ ......................... ........ ...................... ........ ....17 REPORT LIMITATIONS .......... ........................... ........................................................... 18 APPENDIX SITE VICINITY MAP SOIL BORING LOCATION PLAN GENERAL NOTES SOIL BORING LOGS (8) UNIFIED SOIL CLASSIFICATION SYSTEM ~'\ . --:: ~, -1- PROJECT INFORMATION Proiect Authorization Professional Service Industries, Inc. (PSI) has completed a geotechnical exploration for the proposed Red Robin restaurant at 99th Street and Michigan Road in Carmel, Indiana. PSI's services were authorized by Mr. John Finnemore of Red Robin International, Inc. on May 31, 2006 by signing our proposal. This exploration was accomplished in general accordance with PSI Proposal No. 691-6e0045, dated May 30, 2000 and referenced the Master Service Agreement (MSA) dated October 5, 2005. Proiect Description Project information was provided by Mr. John Finnemore in an email dated May 17, 2006. PSI received the following project information: . A Preliminary Site Plan, dated April 26, 2006 . A Utility Plan titled, "Entrance Areas", dated October 20, 2004, prepared by Woolpert, Inc., prepared for Duke Realty Corporation . A plan titled, "SP-8", dated January 2006, prepared for Duke Realty Corporation. PSI understands the proposed construction will be as follows: Building . Single-story building with a floor area of about 6,000 sf . Steel frame with non-load bearing masonry perimeter walls . Maximum bay spacing of about 20 feet with maximum design column loads not exceeding 40 kips . Maximum continuous wall loads not exceeding 3 kif . Concrete slabs-on-grade floors with maximum design floor loads of 100 to 125 psf . No below-ground spaces, such as a basement Grading . Up to one foot of cuUfill in the building area (basis of report) . Up to two feet of cuUfill across the property (basis of report) Pavement . The building will be surrounded by access and parking pavements, including a dumpster pad. The geotechnical recommendations presented in this report are based on the available project information, building location, and the subsurface conditions described in this report. If PSI's basis of report or understandings of the project are considered incorrect or if conditions during construction are significantly different from those described in this report, please inform PSI PSI Project No. 691-88070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. .." -- . -2- immediately in writing so that PSI may amend the recommendations presented in this report, if appropriate and if desired by the client. PSI will not be responsible for the implementation of its recommendations when it is not notified of changes in the project. Purpose and Scope of Services The purpose of this study was to explore the subsurface conditions at the site in order to develop earthwork and foundation related design recommendations for the proposed construction. PSI's scope of services included drilling eight (8) soil borings at the site to depths of about 10 to 15 feet below the existing ground surface, select laboratory testing, and preparation of this geotechnical report. This report briefly outlines the testing procedures, presents available project information, describes the site and subsurface conditions, and presents geotechnical recommendations regarding the following: . A discussion of the subsurface conditions encountered including pertinent soil properties and groundwater conditions encountered at the time of drilling . An evaluation of the data as it relates to the proposed site development . An interpretation of the Site Class in accordance with Table 1615.1.1 of the International Building Code, 2003 Ed. . Recommendations for site preparation, including placement and compaction of soils . Geotechnical recommendations to support foundation and pavement design . Comments and recommendations relating to other observed geotechnical conditions which could impact development The scope of services of this report did not include an environmental assessment for determining the presence or absence of wetlands, or hazardous or toxic materials in the soil, bedrock, surface water, groundwater, or air on or below, or around this site. Any statements in this report or on the boring logs regarding odors, colors, and unusual or suspicious items or conditions are strictly for informational purposes. PSI has performed an environmental site assessment for this property. The report has been submitted under separate cover. Under the terms of PSI Proposal No. 691-6e0045, dated May 30, 2006, and the MSA, PSI did not provide any service to investigate or detect the presence of moisture, mold or other biological contaminates in or around any structure, or any service that was designed or intended to prevent or lower the risk of the occurrence of the amplification of the same. As stated in the above referenced proposal, mold is ubiquitous to the environment with mold amplification occurring when building materials are impacted by moisture. Site conditions are outside of PSI's control, and mold amplification will likely occur, or continue to occur, in the presence of moisture. As such, PSI cannot and shall not be held responsible for the occurrence or recurrence of mold amplification. PSI Project No. 691-68070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. ~ ;:-'\ .. -3- SITE AND SUBSURFACE CONDITIONS Site Location and Description The 1.68 acre site for the proposed Red Robin restaurant is located on the northeast corner of Michigan Road and 99th Street in Carmel, Indiana. It is bordered by a gas station to the north, 99th Street to the south, an access drive to the east, and North Michigan Road to the west. The site latitude and longitude are approximately N39055'59" and W86013'56", respectively. The general site location is shown on Figure 1, Site Vicinity Map, in the Appendix of this report. The ground surface elevation across the generally flat site was approximately 890 feet. The ground surface elevations were interpolated from the topographic quadrangle survey prepared by the United States Geological Survey (USGS). Construction equipment and materials were located across the site at the time of drilling, including two construction trailers located within the approximate footprint of the proposed building. The asphalt covering the site and surficial soils were firm at the time of the field exploration. PSI's truck mounted-drill rig experienced no difficulty in moving about the site. Site Geology Based on the on-line geologic map provided by the Indiana Geological Society, available at http://igs.indiana.edu/arcims/statewide/index.html, the proposed site is located on the Tipton Till Plain which is part of the Central Till Plain. Overburden soils in the project area consist of loam till deposits from the Huron-Erie Lobe of the Wisconsinan Glacier. The thickness of the unconsolidated deposits in the project area is reported to be between 150 and 200 feet. The site is mapped as underlain by New Albany Shale of the Mississippian and Devonian ages. Subsurface Conditions The site subsurface conditions were explored with eight (8) soil test borings, four (4) within the proposed building area and four (4) within parking and drive areas. Building borings were advanced to depths of 15 feet below existing grades and pavement borings were advanced to depths of 10 feet below existing grades. The boring locations and depths were suggested by PSI per the MSA. PSI personnel staked the borings in the field by measuring distances from available surface features. The surface elevations at the borings were referenced to the USGS Carmel, IN quadrangle. The borings were advanced utilizing 3~-inch inside diameter hollow stem auger drilling methods and soil samples were routinely obtained during the drilling process. Select soil samples were later tested in PSI's laboratory to document material properties. Drilling, sampling, and laboratory testing were accomplished in general accordance with ASTM procedures. PSI Project No. 691.6e070, Red Robin Restaurant- Carmel, Indiana Professional Service Industries, Inc. --". ... -4- Below 3 to 12 inches of asphalt and/or crushed stone, the subsurface conditions, primarily included undocumented fill, possible fill and natural silty clay as identified by the eight (8) borings performed for this project. These materials are described in more detail in the following paragraph. Undocumented fill and possible fill, consisting of gray and black silty clay, was encountered in borings B-4, P-1, P-3 and P-4 to depths ranging from 3 feet below existing grade at boring B-4 to 10 feet below existing grade at boring P-1. Underlying the fill and possible fill and crushed stone and asphalt, brown silty clay was encountered to depths ranging from the explored depth of 10 feet in boring P-2 to 13 feet below existing grades in borings B-1, B-2, B-3 and B-4. Underlying the brown silty clay, gray silty clay was encountered to the explored depth of 20 feet below existing grade in borings B-1, B-2, B-3 and B-4. The following table briefly summarizes the range of results from the field and laboratory testing programs. Please refer to the attached boring logs and laboratory data sheets for more specific information: z C ~ 0 0 "0.. Q) . .... (1l :;t: (1l ... "OQ) (;52 c: c: .- c: .11l Q) o 0 000.. ~C,) Black and gray silty Y2 - 10 4-27 16 - 25 CLAY Upper brown silty Y2 - 5 7-24 11 - 24 CLAY Brown silty CLAY 5-13 7-18 10 - 20 Gray silty CLAY 13 - 20 22 - 43 7-9 The above subsurface description is of a generalized nature to highlight the major subsurface stratification features and material characteristics. The boring logs included in the appendix should be reviewed for specific information at individual boring locations. These records include soil descriptions, stratifications. penetration resistances, locations of the samples and laboratory test data. The stratifications shown on the boring logs represent the conditions only at the actual boring locations. Variations may occur and should be expected between boring locations. The stratifications represent the approximate boundary between subsurface materials and the actual transition may be gradual. Groundwater information obtained during field operations is also shown on these boring logs. The samples that were not altered by laboratory testing will be retained for 60 days from the date of this report and then will be discarded. Professional Service Industries, Inc. PSI Project No. 691-68070, Red Robin Restaurant - Carmel, Indiana -5- Groundwater Information Water levels were noted in the borings during and at completion of drilling and at up to 2 hours following completion of drilling. The water level in boring B-3 at completion of drilling, following removal of the augers, was reported at a depth of about 11 feet below existing grade, approximate elevation 879 feet. The water levels in borings B-2 and B-3 up to 2 hours after completion of drilling, following removal of the augers, were reported at depths of about 6Y2 and 10 feet, respectively, below existing grades, approximate elevations 880 to 884 feet. The remaining borings were reported "dry" during and upon completion of drilling, meaning that no free water was observed in the borehole or on the sampling tools. The "dry" conditions indicate that the continuous groundwater level at the site at the time of the exploration was either below the terminated or cave-in depths of the borings, or that the soils encountered were relatively impermeable. The cave-in depths, following the removal of the augers, ranged from 9 to 12 feet below existing grades. In fine-grained soils such as the silty clay at this site, the water levels in the boreholes are often not representative of the actual groundwater level, because the boreholes remain open for a relatively short time. To obtain longer-term measurements, it is necessary to install water level observation wells or piezometers. In fine-grained soils, the depth of the soil color change from brown to gray can be an indicator of the prevailing groundwater level. Above the prevailing groundwater level, fine-grained soils oxidize to a brown color. At this site, the transition from brown to gray soils generally occurred at a depth of about 13 feet below existing grade, at about elevation 877 feet. Based on the water level observations during drilling, the moisture content of the recovered granular soil samples, and the depth of color change of fine grained soils in the borings, PSI estimates the prevailing groundwater level may be at or below a depth of about 13 feet below existing grade, at approximate elevation 877 feet. Localized zones of apparent perched water were observed at depths of 11 feet in boring 8-11 and may be present elsewhere at shallower depths depending on seasonal conditions. Saturated soils were encountered in the borings at depths shallower than 11 feet and will likely produce water in open excavations. The groundwater level at the site, as well as perched water levels and volumes, will fluctuate based on variations in rainfall, snowmelt, evaporation, surface run-off and other related hydrogeologic factors. The groundwater levels discussed in this section, and shown on the boring logs, represent the conditions at the time the observations were made. PSI Project No. 691-6e070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. .. -6- EVALUATION AND RECOMMENDATIONS Geotechnical Discussion The following geotechnical related recommendations have been developed on the basis of the subsurface conditions encountered and PSI's understanding of the proposed development. Should changes in the project criteria occur, a review must be made by PSI to determine if modifications to our recommendations will be required. There are three primary geotechnical related concerns at this site, which may affect the performance of the foundations and other related construction for this structure. The following summarizes those concerns: 1. Existing undocumented fill and possible fill material was encountered within the proposed building and parking areas. 2. Drying of some of the on site soils may be required to achieve proper compaction during grading. 3. Relatively high water table may present construction difficulties for utility excavations. Site Preparation PSI recommends that topsoil, vegetation, roots, frozen and soft soils in the construction areas be stripped from the site and either wasted or stockpiled for later use in non-load bearings areas. Depths of crushed stone and asphalt in PSI's borings ranged from 3 to 12 inches. The depth of removal should be determined by a representative of the geotechnical engineer at the time of construction. After stripping and excavating to the proposed subgrade level, as required, the building and parking areas should be thoroughly proof-rolled with a loaded tandem axle dump truck or similar piece of heavy rubber tired vehicle (typically with an axle load greater than 9-tons). Soils that are observed to rut or deflect excessively (typically greater than 1-inch) under the moving load should be undercut and replaced with properly compacted fill. The proofrolling and undercutting activities should be observed and documented by a representative of the geotechnical engineer and should be accomplished during a period of dry weather. Soft, loose or unstable areas revealed by the proofrolling should be stabilized by additional compaction or undercut and replaced with engineered fill or crushed aggregate. When backfilling impervious subgrades with granular soil, a means of drainage should be provided, such as edge drains, drain tiles, or if the slope warrants, gravity draining the granular material to a surface exit point. If proofrolling is performed following a warm and dry period, the need for surface repairs may generally be limited to localized areas. However, if subgrade preparation must proceed during unfavorable wet and/or cool weather periods, such as early spring or late fall, more extensive surface repairs will likely be required, as discussed in the Construction Considerations section of this report. PSI Project No. 691-68070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. -7- After stripping, cutting to grade, and proofrolling have been completed, fill placement to establish construction grades may begin. The first layer of fill should be placed in a relatively uniform horizontal lift and be adequately keyed into the stripped and scarified subgrade soils. Engineered fill materials to be placed within building and pavement areas should be free of organic or other deleterious materials, have a maximum particle less than 3 inches, and have a liquid limit less than 40 and a plasticity index less than 20. Most of the on site soils are anticipated to be suitable for use as engineered fill for site grading within building and pavement areas. If the on-site silty clay soils or imported fine-grained silt or clay soils are used for fill, close moisture content control will be required to achieve the recommended degree of compaction. The moisture contents of the majority of the near surface silty clay soils are over 20 percent and will likely require drying prior to placement as engineered fill. Optimum moisture contents for the silty clay soils are likely to be in the range of 9 to 15 percent. PSI anticipates disking and aeration during a warm, dry period will likely be necessary to lower the moisture content. If engineered fill placement must proceed during a wet or cool time of the year, it will likely be infeasible to use the on-site soils as engineered fill, and imported fill materials will be required. If wet or cool season earthwork is necessary, PSI recommends the use of imported fill materials meeting the requirements of Indiana Department of Transportation (INDOT) 2006 Standard Specifications Section 211, "B" Borrow. In utility trenches, shallow foundation excavations, and other areas where large compaction equipment cannot be used, granular engineered fill should be placed as backfill. PSI recommends the use of material meeting Indiana Department of Transportation (INDOT) 2006 Standard Specification Section 904, Structure Backfill, for use as granular engineered fill. Engineered fill should be placed in accordance with the recommendations stated in this section of the report. The fill placed shall be tested and documented by a geotechnical technician as directed by a geotechnical engineer. It should be noted that the geotechnical engineer of record can only certify the testing that is performed and the work observed and documented by that engineer or staff directly reporting to that engineer. The following table summarizes the recommended compaction for various types of engineered fills. PSI Project No. 691-6e070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. -8- MATERIAL TESTED PROCTOR MIN % MOISTURE FREQUENCY OF TYPE DRY CONTENT TESTING '-2 DENSITY RANGE Structural Fill (Cohesive) Modified 95% -2 to +2 % 1 oer 1 ,000 cv of fill olaced Structural Fill (Granular) Modified 95% -2 to +2 % 1 per 1,000 Cy of fill placed Optional Structural Fill Relative 75% >95% 1 per 1,000 cy of fill placed (Granular) Density , Saturation Random Fill (non-load bearina) Modified 88% -3 to +3 % 1 per 3,000 Cy of fill placed Utility Trench Backfill! Wall Modified 90% -2 to +2 % 1 per 200 cy of fill placed Backfill Other -2 to +2 % 1 per 1,000 Cy of fill placed 'Relative Density as determined in general accordance with ASTM 04253 and 04254 '-2 Minimum of 1 test per lift Tested fill materials that do not achieve either the required dry density or moisture content range shall be recorded, the location noted, and reported to the Contractor and Owner. A re-test of that area should be performed after the Contractor performs remedial measures. Foundation Recommendations The planned construction can be supported on conventional spread footing foundations bearing on either competent naturally deposited silty clay soils classified as firm or stiffer per ASTM 02488 or properly compacted structural fill placed on suitable natural soils. The existing fill soils are not suitable for foundation support. Spread footings for building columns and continuous footings for bearing walls may be designed for allowable soil bearing pressures of 2,500 psf and 2,000 psf, respectively, based on dead load plus design live load. Minimum plan dimensions of 24 inches for column footings and 18 inches for continuous footings should be used in foundation design to provide an acceptable factor of safety against a local bearing capacity and punching shear failure and provide adequate room for cleaning of the bearing surface. Exterior footings and footings in unheated areas should bear at a depth of at least 36 inches below the final exterior grade to provide adequate frost protection. If the building is to be constructed during the winter months or if footings will likely be subjected to freezing temperatures after foundation construction, then all footings should be adequately protected from freezing. Otherwise, interior footings can be located on acceptable bearing materials at nominal depths compatible with architectural and structural considerations. The foundation excavations should be observed and documented by a representative of PSI prior to steel or concrete placement to assess that the foundation materials appear consistent with the materials discussed in this report and are thereby capable of supporting the design loads. Soft or PSI Project No. 691-6e070, Red Robin Restaurant - Carmel, Indiana Professional SeNice Industries, Inc. :: -9- loose soil zones encountered at the bottom of the footing excavations, as indicated by blows with a dynamic cone penetrometer (DCP) equivalent to N-value of 6 or less, and existing fill soils should be removed to the level of suitable natural soils, and replaced with adequately compacted structural fill. Fill placed below the foundations where unsuitable materials are removed should extend one (1) foot outside the foundation limits for every one (1) foot in thickness between the intended bearing surface and the underlying, suitable natural soils. Alternately, the foundations may be extended through unsuitable soils to bear on the underlying suitable material. After opening, foundation bearing surfaces should be observed, tested and documented and concrete placed as quickly as practical to limit exposure of the footing bottoms to water and construction traffic. Surface run-off water should be drained away from the excavations and not be allowed to pond. The foundation concrete should be placed during the same day the excavation is made. If foundation excavations must be left open for more than one day, they should be protected by placement of a lean concrete mud mat or a 3 to 4 inch thick layer of compacted crushed aggregate such as INDOT No. 53 crushed aggregate. Based on results of the field tests and the anticipated foundation loads, PSI estimates that the maximum foundation settlement may be about 1 inch. Differential settlement between two adjacent columns may be about % inch. While settlement of this magnitude is generally considered tolerable for structures of the type proposed, the design of masonry walls should include provisions for liberally spaced, vertical control joints to minimize the effects of cosmetic cracking. Seismic Design Considerations The 2003 International Building Code requires a site class for the calculation of earthquake design forces. This class is a function of soil type (Le., depth of soil and strata types). Soil borings at the project site extended to depths of up to 15 feet. Based on regional geologic mapping, PSI anticipates that the subsurface conditions below the explored depth may generally consist of glacial till. Based on PSI's review of the available data, and knowledge of regional geology, PSI evaluated the Site Class using the weighted average of known and estimated Standard Penetration Test (SPT) N-values, soil shear strength estimated from the field and laboratory tests and regional geologiC information. Site Class" C " is recommended. The USGS-NEHRP probabilistic ground motion values interpolated between the nearest four grid points from latitude 39.93310 and longitude -86.23220 are as follows: Professional Service Industries, Inc. PSI Project No. 691.6e070, Red Robin Restaurant - Carmel, Indiana -10- Period 2% Probability of Event Site Site (seconds) in 50 years * (%g) Coefficient Fa Coefficient Fv PGA 7.61 --- --- 0.2 (S5) 18.19 1.2 --- 0.3 16.73 --- --- 1.0 (S1) 9.02 --- 1.7 The Site Coefficients, Fa and Fv were interpolated for IBC 2003 Tables 1615.1.2(1) and 1615.1.2(2) as a function of the site classifications and the mapped spectral response acceleration at the short (S5) and 1 second (S1) periods. Floor Slab Recommendations The floor slab can be grade supported on natural or fill silty clay soils classified as firm or stiffer per ASTM D2488, or properly compacted/engineered fill. Proofrolling, as discussed earlier in this report, should be accomplished to identify soft or unstable soils that should be removed from the floor slab area prior to fill placement and/or floor slab construction. For subgrade prepared as recommended and properly compacted fill, a modulus of subgrade reaction, k value, of 140 pounds per cubic inch (pci) may be used in the grade slab design based on values typically obtained from 1 foot x 1 foot plate load tests. However, depending on how the slab load is applied, the value will have to be geometrically modified. The value should be adjusted for larger areas using the following expressions for cohesive and cohesion less soil, respectively: Modulus of Subgrade Reaction, k5 = (!) for cohesive soil and B ks = k ( B + 1 )2 for cohesion less soil 2B where: ks = coefficient of vertical subgrade reaction for loaded area, k = coefficient of vertical subgrade reaction for 1x1 square foot area, and B = width of area loaded, in feet PSI recommends that a minimum four-inch thick free draining granular mat be placed beneath the floor slab to enhance drainage. The soil surface shall be graded to drain away from the building without low spots that can trap water prior to placing the granular drainage layer. Polyethylene sheeting should be placed to act as a vapor retarder where the floor will be in contact with moisture sensitive equipment or products such as tile, wood, carpet. etc., as directed by the PSI Project No. 691-6e070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. -11- design engineer. The decision to locate the. vapor retarder in direct contact with the slab or beneath the layer of granular fill should be made by the design engineer after considering the moisture sensitivity of subsequent floor finishes, anticipated project conditions and the potential effects of slab curling and cracking. The floor slabs should have an adequate number of joints to reduce cracking resulting from differential movement and shrinkage. The precautions listed below should be followed for construction of slabs-on-grade. These details will not reduce the amount of movement, but are intended to reduce potential damage should some settlement of the supporting subgrade take place. Some increase in moisture content is inevitable as a result of development and associated landscaping. However, extreme moisture content increases can be largely controlled by proper and responsible site drainage, building maintenance and irrigation practices. . Cracking of slab-on-grade concrete is normal and should be expected. Cracking can occur not only as a result of heaving or compression of the supporting soil and/or bedrock material, but also as a result of concrete curing stresses. The occurrence of concrete shrinkage cracks, and problems associated with concrete curing may be reduced and/or controlled by limiting the slump of the concrete, proper concrete placement, finishing, and curing, and by the placement of crack control joints at frequent intervals, particularly where re-entrant slab corners occur. The American Concrete Institute (ACI) recommends a maximum panel size (in feet) equal to approximately three times the thickness of the slab (in inches) in both directions. For example, joints are recommended at a maximum spacing of twelve (12) feet based on a four-inch slab. PSI also recommends that the slab be independent of the foundation walls. . Areas supporting slabs should be properly moisture conditioned and compacted. Backfill in all interior and exterior water and sewer line trenches should be carefully compacted to reduce the shear stress in the concrete extending over these areas. Exterior slabs should be isolated from the building. These slabs should be reinforced to function as independent units. Movement of these slabs should not be transmitted to the building foundation or superstructure. General Pavement Recommendations PSI's scope of services did not include extensive sampling and CBR testing of the existing subgrade or potential sources of imported fill for the specific purpose of detailed pavement section analysis. Instead, PSI has based this report on pavement-related design parameters that are considered to be typical for the area soils types. In large areas of pavement, or where pavements are subject to significant traffic, a more detailed analysis of the subgrade and traffic conditions should be made. The results of such a study will provide information necessary to design an economical and serviceable pavement. The recommended thicknesses presented below are considered typical and minimum for the PSI Project No. 691.6e070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. -12- parameters used in this report. PSI understands that given budgetary considerations, it is desirable to place thinner pavement sections than those presented. However, the client, the owner, and the project principals should be aware that thinner pavement sections might result in increased maintenance costs and lower than anticipated pavement life. The pavement subgrade should be prepared as discussed in the "Site Preparation" section of this report. PSI has estimated the subgrade soils will be prepared to achieve a minimum CBR of 3. Based on this value, it is possible to use a locally typical "standard" pavement section consisting of the following: , Recommended Thicknesses (Inches)* " Pavement Materials ** Car Parking Driveways Asphaltic Surface Course 1Y2 1Y2 Asphaltic Binder Course 2Y2 3Y2 Crushed stone (3/4-inch minus) 6 6 Or Portland Cement Concrete 5 6 Crushed stone (3/4-inch minus) 4 4 * Pavement sections were evaluated using Pavement Assessment Software (PAS) which is based on the 1986 MSHTO Design equations: a reliability of 80%; and a 20-year 18-kip single axle load (ESAL) of 30.000 for light duty and 60.000 for drive areas. Flexible Pavements were evaluated based on an initial serviceability of 4.2 and a terminal serviceability of 2.0. Rigid Pavements were evaluated based on an initial serviceability of 4.5 and a terminal serviceability of 2.0; an unreinforced concrete mix with a 28 day modulus of rupture of 550 psi (approx. 3.000 psi compressive strength) ** Pavement materials should conform to local and state guidelines. if applicable. Pavement for the dumpster area should be constructed of at least an a-inch thick, properly reinforced, Portland cement concrete section with load transfer devices installed where construction joints are required. A thickened edge is recommended on the outside of slabs subjected to wheel loads. This thickened edge usually takes the form of an integral curb. Fill material should be compacted behind the curb or thickened edge of the outside slabs. The following are recommended to enhance the quality of the pavement: . Moisten subgrade just prior to placement of concrete. . Cure fresh concrete with a liquid membrane-forming curing compound. . Keep automobile traffic off the slab for 3 days and truck traffic off the slab for 7 days, unless tests are performed to determine that the concrete has gained adequate strength (Le., usually 3,000 psi) PSI Project No. 691.6e070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. -13- The pavement sections listed above were designed for in-service traffic only. If a partially completed pavement section will be utilized by construction traffic, additional analyses will be necessary. Pavement Subgrade PreDaration Prior to paving, the prepared subgrade should be proofrolled using a loaded tandem axle dump truck or similar type of pneumatic tired equipment with a minimum gross weight of 9 tons per single axle. Localized soft areas identified should be repaired prior to paving. Moisture content of the subgrade should be maintained between -2% and +2% of the optimum at the time of paving. It may require rework when the subgrade is either desiccated or wet. Construction traffic should be minimized to prevent unnecessary disturbance of the pavement subgrade. Disturbed areas, as identified by PSI, should be removed and replaced with properly compacted material. Pavement Drainage & Maintenance PSI recommends pavements be sloped to provide rapid surface drainage. Water allowed to pond on or adjacent to the pavement could saturate the subgrade and cause premature deterioration of pavements, and removal and replacement may be required. Consideration should be given to the use of interceptor drains to collect and remove water collecting in the granular base. The interceptor drains could be incorporated with the storm drains of other utilities located in the pavement areas. Periodic maintenance of the pavement should be anticipated. This should include sealing of cracks and joints and maintaining proper surface drainage to avoid ponding of water on or near the pavement area. Professional Service Industries, Inc. PSI Project No. 691-6e070, Red Robin Restaurant - Cannel, Indiana -14- CONSTRUCTION CONSIDERATIONS PSI should be retained to provide observation and testing of construction activities involved in the foundations and pavements, earthwork, and related activities of this project. PSI cannot accept responsibility for conditions which deviate from those described in this report, nor for the performance of the foundations and pavements if not engaged to also provide construction observation and testing for this project. Moisture Sensitive SoilslWeather Related Concerns The upper silty clay soils encountered at this site may be sensitive to disturbances caused by construction traffic and changes in moisture content. During wet weather periods, increases in the moisture content of the soil can cause significant reduction in the soil strength and support capabilities. In addition, soils that become wet may be slow to dry and thus significantly retard the progress of grading and compaction activities. It will, therefore, be advantageous to perform earthwork and foundation construction activities during dry weather. If proofrolling is performed following a warm and dry period, the need for surface repairs may generally be limited to localized areas. However, if subgrade preparation must proceed during unfavorable wet and/or cool weather periods, such as early spring or late fall, more extensive surface repairs will likely be required. For subgrade areas that exhibit unsuitable deflection, rutting and pumping during proofrolling, the following alternatives can be considered to continue with construction and earthwork activities: . Undercutting and replacement with crushed aggregate, as recommended in the Site Preparation section of this report . Undercutting and replacement with a geogrid or geotextile and a lesser thickness of crushed aggregate For localized unstable subgrade areas, undercutting and replacement with crushed aggregate is generally the most cost-effective alternative. For larger areas, or areas of severe subgrade instability, incorporation of a geogrid and/or geotextile may be warranted. The depth of undercutting, geogrid/geotextile selection, and thickness of crushed aggregate should be evaluated by the geotechnical engineer based on the conditions at the time of construction. If subgrade preparation must proceed during a period of wet weather, and widespread areas of the subgrade are unstable, undercutting may be time consuming and costly. It may be impossible to effectively dry the soil if conditions are wet and temperatures are low. As discussed in the Subgrade Preparation section of this report, if earthwork must proceed during other than summer months, it may be difficult or impossible to dry the on-site soils for re-use as fill. If wet or cool season earthwork is necessary, PSI recommends the use of imported fill materials meeting the requirements of Indiana Department of Transportation (INOOT) 2006 Standard Specifications Section 211 J "B" Borrow. PSI Project No. 691-6e070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. :.. -15- Drainage and Groundwater Considerations Water should not be allowed to collect in the foundation excavations, on floor slab areas, or on prepared subgrades of the construction area either during or after construction. Undercut or excavated areas should be sloped toward one corner to facilitate removal of any collected rainwater, groundwater, or surface runoff. Positive site surface drainage should be provided to reduce infiltration of surface water around the perimeter of the building and beneath the floor slabs. The grades should be sloped away from the building and surface drainage should be collected and discharged such that water is not permitted to infiltrate the backfill and floor slab areas of the building. Groundwater was measured in borings B-2 and B-3 at depths ranging from 6~ to 11 feet below existing grades. However, it is possible that seasonal variations will cause fluctuations, or a water table to be present in the upper soils at a later time. Additionally, perched water may be encountered in discontinuous zones within the overburden. Water should be removed from excavations by pumping. PSI anticipates groundwater or perched water seepage and surface drainage can likely be managed by localized dewatering using conventional sump and pump methods. Should excessive and uncontrolled amounts of seepage occur, the geotechnical engineer should be consulted. Footing drains should be installed where foundations are placed within a relatively impervious subgrade and backfilled with granular soils. This will allow water to drain away from the foundation excavations. Excavations In Federal Register, Volume 54, No. 209 (October 1989), the United States Department of Labor, Occupational Safety and Health Administration (OSHA) amended its "Construction Standards for Excavations, 29 CFR, part 1926, Subpart P". This document was issued to better provide for the safety of workers entering trenches or excavations. This federal regulation mandates that excavations, whether they be utility trenches, basement excavation or footing excavations, be constructed in accordance with the OSHA guidelines. It is PSI's understanding that these regulations are being strictly enforced and if they are not closely followed, the owner and the contractor could be liable for substantial penalties. The contractor is solely responsible for designing and constructing stable, temporary excavations and should shore, slope, or bench the sides of the excavations as required to maintain stability of both the excavation sides and bottom. The contractor's "responsible person", as defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of the contractor's safety procedures. In no case should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and federal safety regulations. PSI Project No. 691.6e070, Red Robin Restaurant - Cannel, Indiana Professional Service Industries, Inc. '" -16- PSI is providing this information solely as a service to Red Robin International. Inc. PSI does not assume responsibility for construction site safety or the contractor's or other parties' compliance with local. state. and federal safety or other regulations. PSI Project No. 691-68070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. ., .-, -17- GEOTECHNICAL RISK The concept of risk is an important aspect of the geotechnical evaluation. The primary reason for this is that the analytical methods used to develop geotechnical recommendations do not comprise an exact science. The analytical tools which geotechnical engineers use are generally empirical and must be used in conjunction with engineering judgment and experience. Therefore, the solutions and recommendations presented in the geotechnical evaluation should not be considered risk-free and, more importantly, are not a guarantee that the interaction between the soils and the proposed structure will perform as planned. The engineering recommendations presented in the preceding section constitutes PSI's professional estimate of those measures that are necessary for the proposed structure to perform according to the proposed design based on the information generated and referenced during this evaluation, and PSI's experience in working with these conditions. PSI Project No. 691-68070, Red Robin Restaurant - Carmel, Indiana Professional Service Industries, Inc. . -::. ..... -18- REPORT LIMITATIONS The recommendations submitted, in this report, are based on the available subsurface information obtained by PSI and design details furnished by Red Robin International, Inc. for the proposed project. If there are any revisions to the plans for this project. or if deviations from the subsurface conditions presented in this report are encountered during construction, PSI should be notified immediately to determine if changes in the foundation recommendations are required. If PSI is not notified of such changes. PSI will not be responsible for the impact of those changes on the project. The geotechnical engineer warrants that the findings, recommendations, specifications, or professional advice contained herein have been made in accordance with generally accepted professional geotechnical engineering practices in the local area. No other warranties are implied or expressed. After the plans and specifications are more complete, the geotechnical engineer should be retained and provided the opportunity to review the final design plans and specifications to check that PSI's engineering recommendations have been properly incorporated into the design documents. At this time, it may be necessary to submit supplementary recommendations. If PSI is not retained to perform these functions, PSI will not be responsible for the impact of those conditions on the project. This report has been prepared for the exclusive use of Red Robin International, Inc. and Wachovia National Bank, NA for the specific application to the proposed Red Robin Restaurant at Michigan Road and 99th Street in Carmel, Indiana. PSI Project No. 691-6e070, Red Robin Restaurant - Carmel, Indiana. Professional Service Industries, Inc.