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HomeMy WebLinkAboutFOSSIL CREEK NURSERY PUD - PRELIMINARY - 40-95 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTJ l .',I V. REPORT TERMINOLOGY (Based on ASTM D653) Expansive Potential The potential of a soil to expand (increase in volume) due to absorption of moisture. Finished Grade The final grade created as a part of the project. Footing A portion of the foundation of a structure that transmits loads directly to the soil. Foundation The lower part of a structure that transmits the loads to the soil or bedrock. Frost Depth The depth of which the ground becomes frozen during the winter season. Grade Beam A foundation element or wall, typically constructed of reinforced concrete, used to span between other foundation elements such as drilled piers. Groundwater Subsurface water found in the zone of saturation of soils, or within fractures in bedrock. Heave Upward movement. Lithologic The characteristics which describe the composition and texture of soil and rock by observation. Native Grade The naturally occuring ground surface. Native So# Naturally occurring on -site soil, sometimes referred to as natural soil. Optimum Moisture The water content at which a soil can be compacted to a maximum dry unit Content weight by a given compactive effort. Perched Water Groundwater, usually of limited area maintained above a normal water elevation by the presence of an intervening relatively impervious continuing stratum. Scarify To mechanically loosen soil or break down existing soil structure. Settlement Downward movement. Skin Friction (Side The frictional resistance developed between soil and an element of structure Shear) such as a drilled pier or shaft. Soil (earth) Sediments or other unconsolidated accumulations of solid particles produced by the physical and chemical disintegration of rocks, and which may or may not contain organic matter. Strain The change in length per unit of length in a given direction. Stress The force per unit area acting within a soil mass. Strip To remove from present location. Subbase A layer of specified material in a pavement system between the subgrade and base course. Subgrade The soil prepared and compacted to support a structure, slab or pavement system. Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. REPORT TERMINOLOGY (Based on ASTM D653) Allowable Soil The recommended maximum contact stress developed at the interface of the Bearing Capacity foundation element and the supporting material. Alluvium Soil, the constituents of which have been transported in suspension by flowing water and subsequently deposited by sedimentation. Aggregate Base A layer of specified material placed on a subgrade or subbase usually beneath Course slabs or pavements. Backfill A specified material placed and compacted in a confined area. Bedrock A natural aggregate of mineral grains connected by strong and permanent cohesive forces. Usually requires drilling, wedging, blasting or other methods of extraordinary force for excavation. Bench A horizontal surface in a sloped deposit. Caisson (Drilled pier A concrete foundation element cast in a circular excavation which may have an or Shaft) enlarged base. Sometimes referred to as a cast -in -place pier or drilled shaft. Coefficient of A constant proportionality factor relating normal stress and the corresponding Friction shear stress at which sliding starts between the two surfaces. Coluuvium Soil, the constituents of which have been deposited chiefly by gravity such as at the foot of a slope or cliff. Compaction The densification of a soil by means of mechanical manipulation. Concrete Slab -on- A concrete surface layer cast directly upon a base, subbase or subgrade, and Grade typically used as a floor system. Differential Unequal settlement or heave between, or within foundation elements of a Movement structure. Earth Pressure The pressure or force exerted by soil on any boundary such as a foundation wall. ESAL Equivalent Single Axle Load, a criteria used to convert traffic to a. uniform standard, (18,000 pound axle loads). Engineered Fill Specified material placed and compacted to specified density and/or moisture conditions under observations of a representative of a geotechnical engineer. Equivalent Fluid A hypothetical fluid having a unit weight such that it will produce a pressure against a lateral support presumed to be equivalent to that produced by the actual soil. This simplified approach is valid only when deformation conditions are such that the pressure increases linearly with depth and the wall friction is neglected. Existing Fill (or Materials deposited through the action of man prior to exploration of the site. man-made fill) Existing Grade The ground surface at the time of field exploration. Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. LABORATORY TESTS SIGNIFICANCE AND PURPOSE TEST SIGNIFICANCE PURPOSE California Used to evaluate the potential strength of subgrade soil, subbase, Pavement Bearing and base course material, including recycled materials for use in Thickness Ratio road and airfield pavements. Design Used to develop an estimate of both the rate and amount of both Foundation Consolidation differential and total settlement of a structure. Design Used to determine the consolidated drained shear strength of soil Bearing Capacity, Direct or rock. Foundation Design & Shear Slope Stability Dry Used to determine the in -place density of natural, inorganic, fine- Index Property Density grained soils. Soil Behavior Used to measure the expansive potential of fine-grained soil and to Foundation & Slab Expansion provide a basis for swell potential classification. Design Used for the quantitative determination of the distribution of Soil Gradation particle sizes in soil. Classification Liquid & Used as an integral part of engineering classification systems to Soil Plastic Limit, characterize the fine-grained fraction of soils, and to specify the Classification Plasticity Index fine-grained fraction of construction materials. Oxidation- Used to determine the tendency of the soil to donate or accept Corrosion Reduction electrons through a change of the oxidation state within the soil. Potential Potential Used to determine the capacity of soil or rock to conduct a liquid Groundwater Permeability or gas. Flow Analysis Used to determine the degree of acidity or alkalinity of a soil. Corrosion p H Potential Used to indicate the relative ability of a soil medium to carry Corrosion Resistivity electrical currents. Potential Used to evaluate the potential strength of subgrade soil, subbase, Pavement R-Value and base course material, including recycled materials for use in Thickness road and airfield pavements. Design Soluble Used to determine the quantitative amount of soluble sulfates Corrosion Sulphate within a soil mass. Potential Used to determine the quantitative amounts of sulfides within a Corrosion Sulfide Content soil mass. Potential To obtain the approximate compressive strength of soils that Bearing Capacity Unconfined possess sufficient cohesion to permit testing in the unconfined Analysis for Compression state. Foundations Water Used to determine the quantitative amount of water in a soil mass. Index Property Content Soil Behavior Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests" Coarse -Grained Gravels more than Clean Gravels Less Cu > 4 and 1 < Cc <3E Soils more than 50% of coarse than 5 /6 finesc 50% retained on fraction retained on No. 200 sieve No. 4 sieve Cu < 4 and/or 1 > Cc > 3E Sands 50% or more of coarse fraction passes No. 4 sieve Fine -Grained Soils Silts and Clays 50% or more Liquid limit less passes the than 50 No. 200 sieve Silts and Clays Liquid limit 50 or more Highly organic soils Prim ABased on the material passing the 3-in. (75-mm) sieve 'If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. cGravels with 5 to 12% fines require dual symbols: GW-GM well -graded gravel with silt GW-GC well -graded gravel with clay GP -GM poorly graded gravel with silt GP -GC poorly graded gravel with clay °Sands with 5 to 12% fines require dual symbols: SW-SM well -graded sand with silt SW -SC well -graded sand with clay SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay 60 50 x '0 z U y20 0. 10 7 4 0 0 Soil Classification Group Group Name° ..._I GW Well -graded gravel` GP Poorly graded aravr Gravels with Fines more than 12% finest Fines classify as ML or MH GM Silty gravel,G,H Fines classify as CL or CH GC Clayey gravel'•"-" Clean Sands Less Cu > 6 and 1 < Cc < 3E SW Well -graded sand' than 5% fines' Cu < 6 and/or 1 > Cc > 3E SP Poorly graded sand' Sands with Fines Fines classify as ML or MH SM Silty sand','-' more than 12% fines° Fines Classify as CL or CH SC Clayey sand'-"` inorganic PI > 7 and plots on or above "A line' CL Lean clayl.L•M PI < 4 or plots below "A" line' ML SiltK.�M organic Liquid limit - oven dried Organic clayK•L•M•" < 0.75 OL Liquid limit - not dried Organic Silt K,L.M.0 inorganic PI plots on or above "A" line CH Fat clayK,L,M PI lots below "A" line MH Elastic SiltK,L,M organic Liquid limit - oven dried Organic clayKL,M.v < 0.75 OH Liquid limit - not dried Organic siltK,L,M.° f oraanic matter, dark in color, and orqanic odor PT Peat (p,6)2 aCu=Dca1DLo Cc = DL6 X Dc6 Flf soil contains > 15% sand, add "with sand" to group name. Glf fines classify as CL-ML, use dual symbol GC -GM, or SC-SM. "If fines are organic, add "with organic fines" to group name. 'if soil contains > 15% gravel, add "with gravel" to group name. 'If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. 'if soil contains 15 to 29% plus No. 200, add .with sand" or "with gravel", whichever is predominant. Llf soil contains > 30% plus No. 200 predominantly sand, add "sandy" to group name. °"If soil contains > 30% plus No. 200, predominantly gravel, add "gravelly" to group name. "PI > 4 and plots on or above "A" line. 'PI < 4 or plots below "A" line. 'PI plots on or above "A" line. GPI plots below "A" line. F.r d...lft.l.n of IIn.-graln.E wile / ana nn.-araln.a fwctlon of aoana- �% °raln.E ..0. �� Evu.ti"n of 'R -line "Pannpl to 25.5 V. ,,,rrr LL 0) E:vaudon al V - Ina V1na0.9 16 to G Off' 09- MH OR OH i 10 16 20 30 40 50 80 70 80 °o 100 11C LIQUID LIMIT (LL) Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. DRILLING AND EXPLORATION DRILLING & SAMPLING SYMBOLS: R : Ring Barrel] - 2.42" I.D., 3" O.D., unless otherwise noted SS : Split Spoon - 1%" I.D., 2" O.D., unless otherwise noted PS : Piston Sample ST : Thin -Walled Tube - 2" O.D., unless otherwise noted WS : Wash Sample PA: Power Auger FT: Fish Tail Bit HA : Hand Auger RB : Rock Bit DB : Diamond Bit = 4", N, B BS : Bulk Sample AS : Auger Sample PM : Pressure Meter HS : Hollow Stem Auger DC : Dutch Cone WB : Wash Bore Penetration Test: Blows per foot of a 140 pound hammer falling 30 inches on a 2-inch O.D. split spoon, except where noted. WATER LEVEL MEASUREMENT SYMBOLS: WL : Water Level WS : While Sampling WCI : Wet Cave in WD : While Drilling DCI : Dry Cave in BCR : Before Casing Removal AB : After Boring ACR : After Casting Removal Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels is not possible with only short term observations. DESCRIPTIVE SOIL CLASSIFICATION: Soil Classification is based on the Unified Soil Classification system and the ASTM Designations D-2487 and D-2488. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; they are described as: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are described as: clays, if they are plastic, and silts if they are slightly plastic or non -plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse grained soils are defined on the basis of their relative in -place density and fine grained soils on the basis of their consistency. Example: Lean clay with sand, trace gravel, stiff (CL); silty sand, trace gravel, medium dense ISM). CONSISTENCY OF FINE-GRAINED SOILS: Unconfined Compressive Strength, Qu, psf Consistency < 500 Very Soft 500 - 1,000 Soft 1,001 - 2,000 Medium 2,001 - 4,000 Stiff 4,001 - 8,000 Very Stiff 8,001-16,000 Very Hard RELATIVE PROPORTIONS OF SAND AND GRAVEL Descriptive Term(s) (of Components Also Percent of Present in Sample) Dry Weight Trace < 15 With 15 - 29 Modifier > 30 RELATIVE PROPORTIONS OF FINES Descriptive Term(s) (of Components Also Percent of Present in Sample) Dry Weight Trace < 5 With 5 - 12 Modifier > 12 RELATIVE DENSITY OF COARSE -GRAINED SOILS: N-Blows/ft. Relative Density 0-3 Very Loose 4-9 Loose 10-29 Medium Dense 30-49 Dense 50-80 Very Dense 80+ Extremely Dense GRAIN SIZE TERMINOLOGY Major Component of Sample Size Range Boulders Over 12 in. (300mm) Cobbles 12 in. to 3 in. (300mm to 75mm) Gravel 3 in. to #4 sieve (75mm to 4.75mm) Sand #4 to #200 sieve (4.75mm to 0.075mm) Silt or Clay Passing #200 Sieve (0.075mm) Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. 0.5 1.0 1.5 S W E L L 2.0 9'0 C 0 2.5 N S 0 L I D A 3.0 T I 0 N 3.5 APPLIED PRESSURE, TSF Boring and depth (Ft.) Classification DD MC 7 101 3 3.0 1 Sandy Lean Clay 109 17 PROJECT Fossil Creek Nursery, Greenhouse & Parking JOB NO. 2095507 Lot - 4919 South College Avenue DATE 7/20/95 CONSOLIDATION TEST TERRACON Consultants Westem,Inc. V O I D R A T I O ).520 ).515 ).510 ).505 ).500 ).495 ).490 D.485 D.480 0.475 0.470 0.465 0.460 0.1 1 10 APPLIED PRESSURE, TSF Boring and depth (Ft.) IClassification DD MC% 101 3 3.0 1 Sandy Lean Clay 109 17 PROJECT Fossil Creek Nurserv. Greenhouse & Parking JOB NO. 20955107 Lot - 4919 South College Avenue DATE 7/20/95 CONSOLIDATION TEST TERRACON Consultants Westem,lnc. LOG OF BORING No. 5 Page 1 of 1 CLIENT ARCHITECT / ENGINEER Jim Sell Design Jim Sell Design SITE 4919 South College Avenue PROJECT Fort Collins, Colorado Fossil Creek Nu ery, Greenhouse & Parking Lot SAMPLES TESTS m H J F U_ w w 0 DESCRIPTION cn w z\ w LLLD m H M x x w > Icn L 0 z z Q� 0- H fn m w O 3 to ow w 0- U S 0- U FO H }w UWLi F- w m O } w 0- J O 0: U z I— cn F- cD o x z w cnrn s oa xcna ¢ " " " 0.5 6" TOPSOIL CL CANDY LEAN CLAY 7 31/17/14 Tan, moist, medium stiff i A-6(5) 4.0 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS ���RIG BORING STARTED 7-10-95 UZ None 1 BORING COMPLETED 7-10-95 LWL: Hand Auger FOREMAN DML Hole filled In A.B. APPROVED NHS JOB N 20955107 LOG OF BORING No. 4 Page 1 of 1 CLIENT ARCHITECT / ENGINEER Jim Sell Design Jim Sell Design SITE 4919 South College Avenue PROJECT Fort Collins, Colorado Fossil Creek Nursery, Greenhouse & Parking Lot SAMPLES TESTS F \ Y H O !, OJ J O co U_W Z C U_ >- cHA 2 DESCRIPTION N w z\ � w LL(D m H w 2 W cn a z z Q: CL F- to 0W O 3 U)O W W er U z 0- U F- O H >_ LL U a: u_ H W w O } W 0-J O 0_U ZHN H LDD O O Z H x wM E Oa- OV7 a. cc FILL-3" Base course with 1.0 lean clay with sand Brown, moist CL 29/17/12 SANDY LEAN CLAY A-6(4) Tan, moist, medium stiff 4.0 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS wr L® lrw2o"'RIG BORING STARTED 7-10-95 µL SL None = BORING COMPLETED 7-10-95 WL Hand Auger FOREMAN Dom, WL Hole filled in A.B. APPROVED NRS JOB N 20955107 LOG OF BORING No. 3 Page 1 of 1 CLIENT ARCHITECT I ENGINEER Jim Sell Design Jim Sell Design SITE 4919 South College Avenue PROJECT Fort Collins, Colorado Fossil Creek Nursery, Greenhouse & Parking Lot SAMPLES TESTS m E 7 z W 0_ Y >- w O U W w U. z 3 HO 0-J In m \ W w f~A H O t= Y (n w YLL. MU o o_ Z S Hc_ O W L)=LL. ZH(n M cn n. CD H (L Q W DESCRIPTION .� U_ F=LU - O_ W o J co E y (n U (n FILL -Sandy lean 1 SS 12" 5 18 clay with gravel 1.5 Brown, moist CL 2 ST 12" 16 104 3 SS 12" 2 16 SANDY LEAN CLAY 5 Tan, moist, soft to medium stiff 4 ST 12" 18 105 2740 5 SS 12" 5 19 10 6 SS 12" 7 21 15.0 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS � BORING STARTED 7-6-95 Q None W.D.Irerracu" BORING COMPLETED 7�6_95 I� RIG CI�NIE-55 FORE D1YIL WI Hole filled in A.B. APPROVED NRS JJOB# 20955107 LOG OF BORING No. 2 Page 1 of 1 CLIENT ARCHITECT / ENGINEER Jim Sell Design Jim Sell Design SITE 4919 South College Avenue PROJECT Fort Collins, Colorado Fossil Creek Nursery, Greenhouse & Parking Lot SAMPLES TESTS 0! W M z z W a. } H >- Q� W > O U W W W z\ i cn 3 F-O G-J 000 \ W M O F cn H O S Y N z W O >-LL d'U oa z S HF LL CD z z OW UO:LL zF-fn Na ww�- J F-z [n ¢ W !- JJz 070 cncnU CD J U H = (L CC 0: W DESCRIPTION LLLL .. 2 H W o J fa } to W U U)7 xxxFILL-Sandy lean 1 SS 12" 6 10 1.0 clay with gravel Brown, moist i 0.004 CL 2 ST 12" 14 108 3530 SANDY LEAN CLAY Tan, moist, soft 3 SS 12" 3 17 5 4 ST 12" 16 108 2740 5 SS 12" 4 15 10 6 SS 12" 4 27 15.0 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 7-6-95 WL 9 None W.D.W.D• BORING COMPLETED 7-6-95 WI Alrerraccin RIG CME-55 FOREMAN DML WL Hole filled in A.B. APPROVED NRS JOB N 20955107 LOG OF BORING No. 1 Page 1 of 1 CLIENT ARCHITECT / ENGINEER Jim Sell Design Jim Sell Design SITE 4919 South College Avenue PROJECT Fort Collins, Colorado Fossil Creek Nursery, Greenhouse & Parking Lot SAMPLES TESTS M W to E O z W (L } w : O U W M W Z� i (A 3 F_O dJ w0 N W � F- N H O E >- N w O >-LL 0�U Ca- Z 2 LLCD z z O W UMLL ZH-(A (na. W � J (A J (n W WIL =M(A (nn.n. J H 2 (L ¢ LD DESCRIPTION r U_ 2 F a. W o J 03 z (n (A U w 0.5 FILL -Sandy lean claX�moist� 1 SS 12" 3 17 tow i 190 CL 2 ST 12" 18 105 2330 SANDY LEAN CLAY Tan, moist, soft 3 SS 12" 4 17 5 4 ST 12" 15 108 3300 5 SS 12" 3 16 10 — - 6 SS 12" 4 25 15.0 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS 1rerr womuc I BORING STARTED 7-6-95 WL 4 None W.D.= BORING COMPLETED 7-6-95 WL I ]A RIG CME-55 FOREMAN DML WL Hole filled in A.B. APPROVED NRS JOB N 20955107 FIGURE 1: SITE PLAN Ui .ei-919 sou'ri-i COLLEGE AVENUE FOR,r CO.[-.T-,INS, QDLORADO SCALE I" = 200' ELL No. 2095.5107 CONSULTANTS WFSTERN, INC. EMPIRE LAHORA'rojuES DIVISION Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 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 excavation, grading, foundation and construction phases of the work. Observation of footing excavations should be performed prior to placement of reinforcing and concrete 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. 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. 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. 13 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 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 facility. 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 5 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. 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 walls. Landscaped irrigation adjacent to the foundation system should be minimized or eliminated. • Corrosion Protection: Results of soluble sulfate testing indicate that ASTM Type 1-II Portland cement is suitable for all concrete on or below grade. 12 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 Minimum Percent Material (ASTM D698) Subgrade soils beneath fill areas ..................... 95 On -site soils or approved imported fill: Beneath foundations ......................... 98 Beneath slabs ............................. 95 Beneath pavements ......................... 95 Aggregate base (beneath slabs) ...................... 95 Miscellaneous backfill ............................. 90 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 compacted to a minimum of 75 percent relative density as determined by ASTM D4253 D4254. • 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. s Excavation and Trench Construction: Excavations into the on -site soils may encounter caving soils and possibly groundwater, depending upon the final depth of excavation. 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. 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. 11 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 • general site grading • foundation areas • interior floor slab areas • exterior slab areas • pavement areas • foundation backfill 2. Frozen soils should not be used as fill or backfill. 3. Imported soils (if required) should conform to the following or be approved by the Project Geotechnical Engineer: Gradation Percent finer by weight (ASTM C136) 6.. ......................................... 100 3.. ....................................... 70-100 No. 4 Sieve .................................. 50-80 No. 200 Sieve .............................. 60 (max) • Liquid Limit ........................... 30(max) • Plasticity Index ......................... 15 (max) 4. Aggregate base should conform to Colorado Department of Transportation Class 5 or 6 specifications. Select subbase should conform to Colorado Department of Transportation Class 1 specifications. • Placement and Compaction: 1. Place and compact fill in horizontal lifts, using equipment and procedures that will produce recommended moisture contents and densities throughout the lift. 2. No fill should be placed over frozen ground. 3. Materials should be compacted to the following: 10 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 4. Demolition of existing building should include removal of any foundation system. All materials derived from the demolition of existing structures and pavements should be removed from the site and not be allowed for use in any on -site fills. 5. All exposed areas which will receive fill, floor slabs and/or pavement, 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. 2. On -site clay soils in proposed pavement areas 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: a Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 • Maximum Water Content ................... 0.49 lb/lb of cement • Maximum Allowable Slump .......................... 4 inches Concrete should be deposited by truck mixers or agitators and placed a maximum of 90 minutes from the time the water is added to the mix. Other specifications outlined by the Colorado Department of Transportation should be followed. 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 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 Subgrade Preparation: 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 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. 0 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 Aggregate base course (if used on the site) should consist of a blend of sand and gravel which meets strict specifications for quality and gradation. Use of materials meeting Colorado Department of Transportation (CDOT) Class 5 or 6 specifications is recommended for base course. In addition, the base course material should be moisture stable. Moisture stability is determined by R-value testing which shows a maximum 12 point difference in R-values between exudation pressures of 300 psi and 100 psi. Aggregate base course material should be tested to determined compliance with these specifications prior to importation to the site. Aggregate base course and select subbase should be placed in lifts not exceeding six inches and should be compacted to a minimum of 95% Standard Proctor Density (ASTM D698). Asphalt concrete and/or 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 and/or asphalt concrete should conform to approved mix designs stating the Marshall or Hveem properties, optimum asphalt content, job mix formula and recommended mixing and placing temperatures. Aggregate used in plant -mixed bituminous base course and/or asphalt concrete should meet particular gradations. Material meeting Colorado Department of Transportation Grading C or CX specification is recommended for asphalt concrete. Aggregate meeting Colorado Department of Transportation Grading G or C specifications is recommended for plant -mixed bituminous base course. Mix designs should be submitted prior to construction to verify their adequacy. Asphalt material should be placed in maximum 3-inch lifts and should be compacted to a minimum of 95% Marshall or Hveem density (ASTM D1559) (ASTM D1560). 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 • Strength Requirements ........................... ASTM C94 • Minimum Cement Content .................... 6.5 sacks/cu. yd. • Cement Type ................................ Type I Portland o Entrained Air Content .............................. 6 to 8% • Concrete Aggregate ............ ASTM C33 and CDOT Section 703 • Aggregate Size ............................. 1 inch maximum 7 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 • In areas subjected to normal loading, a minimum 4-inch layer of clean -graded gravel should be placed beneath interior slabs. For heavy loading, reevaluation of slab and/or base course thickness may be required. • Floor slabs should not be constructed on frozen subgrade. For structural design of concrete slabs -on -grade, a modulus of subgrade reaction of 150 pounds per cubic inch (pci) may be used for floors supported on existing or engineered fill consisting of on -site soils. Pavement Design and Construction: 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 encountered at the site, the type and volume of traffic and using a group index of"5 as the criterion for pavement design, the following minimum pavement thicknesses are recommended: Recommended Pavement Section Thickn{ ess incliesi Traffic. Area Alter- native Asphalt' Concret' Aggregate Select '; Ptant-Mixed Portland Base Subbase; gkummous Cement Total Course Base Concrete Surface A 3 4 7 Automobile B 2 2Y: 4Y= Parking C 5 5 A 3 7 10 Main 71 Traffic B 2 3 Yz 5 Y, Corridors C 6 6 Each alternative should be investigated with respect to current material availability and economic conditions. Rigid concrete pavement, a minimum of 6 inches in thickness, is recommended at the location of dumpsters where trash trucks will park and load. R Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 Foundation Systems: Due to the presence of non- to low -swelling soils on the site, spread footing foundations bearing upon undisturbed subsoils and/or engineered fill are recommended for support for the proposed structure. The footings may be designed for a maximum bearing pressure of 1,500 psf. The design bearing pressure applies to dead loads plus design live load conditions. The design bearing pressure may be increased by one-third when considering total loads that include wind or seismic conditions. Exterior footings should be placed a minimum of 30 inches below finished grade for frost protection. Interior footings should bear a minimum of 12 inches below finished grade. Finished grade is the lowest adjacent grade for perimeter footings and floor level for interior 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 between adjacent footings. Total settlement resulting from the assumed structural loads is estimated to be on the order of % inch. Proper drainage should be provided in the final design and during construction to reduce the settlement potential. Floor Slab Design and Construction: Non -expansive or low -swelling natural 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 increase 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. 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. Joints should be a minimum of 25% of slab thickness plus '/a inch. • Interior trench backfill placed beneath slabs should be compacted in accordance with recommended specifications outlined below. 5 0 Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 Soil and Bedrock Conditions: The following describes the characteristics of the primary soil strata: • Topsoil. A '/2 foot layer of topsoil with organic matter was encountered in Boring 5. • Fill. A sandy lean clay with gravel fill was encountered in Borings 1, 2, 3 and 4. Overlying the fill in Boring 4 is 3 inches of gravel base course. The clay fill extends to depths of %2 to 1'/2 feet below the surface. • Clay. A sandy lean clay was encountered beneath the topsoil or fill and extended to the depth of the borings. It is tan and moist. Field and Laboratory Test Results: Field test results indicate that the clay soils vary from soft to medium stiff in consistency. Laboratory test results indicate the subsoils at shallow depth have non to low expansive potential and moderate compressibility characteristics. Groundwater Conditions: Groundwater was not observed in any test boring at the time of field exploration. All borings were filled in immediately after drilling. These observations represent 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 weather conditions. CONCLUSIONS AND RECOMMENDATIONS Geotechnical Considerations: The following foundation systems were evaluated for use on the site: • spread footings bearing on undisturbed soils; • spread footings bearing on engineered fill; Design and construction recommendations for foundation systems and other earth connected phases of the project are outlined below. 4 Q Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 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 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 currently occupied by an existing house with a barn and several sheds to the north and west. East and south of the house are pastures. Vegetation consisted of grasses and numerous trees. Site drainage was generally to the east. 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 the Cretaceous Pierre Formation. It is anticipated the bedrock underlies the site at depths of 20 to 25 feet below the surface. The bedrock is overlain by residual or alluvial clays of Pleistocene or Recent Age. 3 Geotechnical Engineering Exploration Jim Sell Design - Terracon Project No. 20955107 SITE 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 analysis. Field Exploration: A total of 5 test borings were drilled on July 6 and 10, 1995 to depths of 4 to 15 feet at the locations shown on the Site Plan, Figure 1. Three borings were drilled within the footprint of the proposed building, and two borings were drilled in the area of proposed pavements. The structure borings were advanced with a truck -mounted drilling rig, utilizing 4-inch diameter hollow stem auger. The pavement borings were hand augered. The borings were located in the field by pacing from existing site features. The accuracy of boring locations should only be assumed to the level implied by the methods used. Continuous lithologic logs of each boring were recorded by the engineering geologist during the drilling operations. At selected intervals, samples of the subsurface materials were 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 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. Groundwater measurements were made in each boring at the time of site exploration. 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 subsurface materials. Boring logs were prepared and are presented in Appendix A. K t \, GEOTECHNICAL ENGINEERING REPORT FOSSIL CREEK NURSERY, P.U.D. FORT COLLINS, COLORADO Terracon Project No. 20955107 July 20, 1995 INTRODUCTION This report contains the results of our geotechnical engineering exploration for the proposed greenhouse and nursery office to be located on South College Avenue. The site is located in the NE %a of Section 14, Township 6 North, Range 69 West of the;6th Principal Meridian. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: • subsurface soil and bedrock conditions • groundwater conditions • foundation design and construction • floor slab design and construction • pavement design and construction • earthwork • drainage The conclusions and recommendations contained in this report are based upon the results of field and laboratory testing, engineering analyses, and experience with similar soil conditions, structures and our understanding of the proposed project. PROPOSED CONSTRUCTION Based on information provided, the proposed project consists of a greenhouse and nursery office and will be a single -story, slab -on -grade metal structure. Wall and column loads are assumed to be less than 3 klf and 30 kips, respectively. Final site grading plans were not available prior to preparation of this report. Ground floor level is anticipated at, or slightly above existing site grade. e r� Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 TABLE OF CONTENTS (Cont'd) APPENDIX A Site Plan .......................................... Figure No. 1 Logs of Borings ..................................... Al thru A5 APPENDIX B Consolidation Tests ................................... 131 thru B2 APPENDIX C: GENERAL NOTES Drilling & Exploration ....................................... C1 Unified Soil Classification .................................... C2 Laboratory Testing, Significance and Purpose ...................... C3 Report Terminology ........................................ C4 I It, Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 TABLE OF CONTENTS Page No. Letter of Transmittal ............................................... ii 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 ............................ 4 Geotechnical Considerations .................................. 4 Foundation Systems ........................................ 5 Floor Slab Design and Construction ............................. 5 Pavement Design and Construction ............................. 6 Earthwork ................................................ 8 Site Clearing and Subgrade Preparation ...................... 8 Excavation ......................................... 9 Fill Materials ........................................ 9 Placement and Compaction 10 Compliance......................................... 11 Excavation and Trench Construction ........................ 11 Drainage................................................ 12 Surface Drainage ..................................... 12 Corrosion Protection ................................... 12 GENERAL COMMENTS ............. ..... _ 13 ...__.. r, July 20, 1995 Jim Sell Design 117 East Mountain Avenue Fort Collins, CO 80524 Attn: Mr. Jim Sell Re: Geotechnical Engineering Report Fossil Creek Nursery, P.U.D. Fort Collins, Colorado Terracon Project No. 20955107 Terracon Consultants Western, Inc. (Terracon) has completed a geotechnical engineering exploration for the proposed project to be located on College Avenue between County Road 32 and Trilby Road in Fort Collins, Colorado: This study was performed in general accordance with our proposal number D2095178 dated June 7, 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 accompanying geotechnical report presents our findings and recommendations concerning the design and construction of foundations and general site development. Further details are provided in this report. We appreciate the opportunity to be of service to you on this phase of your project. If you have any questions concerning this report, or if we may be of further service to you, please do not hesitate to contact us. Sincerely, TERRACON CONSULTANTS WESTERN, INC. Empire Division Prepared by: 4 Larry G. O'Dell, P.E. Office Manager/Principal LGO/NRS/dmf Copies to: Addressee (3) Reviewed b : NeiYR. S od Senior Engineering r .-,O� AT E#4" /�C``o 2575 G a AIPG �i Colo r 4uu p0•f�� C:[ r U Ic Geotechnical Engineering Exploration Jim Sell Design Terracon Project No. 20955107 PROJECT PERFORMANCE EVALUATION Was the work schedule satisfactory? Did project personnel maintain adequate communication during the course of the work? Were the reports easy to follow and understand? Were you satisfied.with the technical competence of the personnel assigned to this project? Do you consider the fees for the project compatible with the services provided? Can this project be used in future marketing efforts conducted by our firm? Would you serve as a client reference for our firm? How would you rate our overall performance on this project? Additional Comments: Yes No Yes No Yes No Yes No Yes No Yes No Yes No Excellent Good Satisfactory Poor, Evaluation completed by: Title: Date: 2 t, R August 1, 1995 Jim Sell Design 117 East Mountain Avenue Fort Collins, CO 80524 Attn: Mr. Jim Sell Re: Geotechnical Engineering Report Fossil Creek Nursery, P.U.D. Fort Collins, Colorado Terracon Project No. 20955107 We appreciate being of service to you and trust that the referenced report has satisfactorily fulfilled your geotechnical engineering requirements for this project. If you have any questions concerning our report, please 'do not hesitate to contact us. We are also prepared to assist you during the design and construction phases of the project. For structural engineering and foundation design services, please contact Mr. Gary Weeks at 970-484-0359. For assistance concerning our construction phase services, please contact Mr. Mike Walker at 970-484-0359. As a valued client, and in an effort to better serve your needs in the future, we would appreciate your candid evaluation of our work. The attached form and the enclosed envelope have been provided to assist you in your response. Any additional personal comments would be especially helpful. We value your business and look forward to being your geotechnical and materials engineering consultant on this and future projects. Thank you for the opportunity to be of service. Sincerely, TERRACON CONSULTANTS WESTERN, INC. Empire Division Larry G. O'Dell, P.E. Office Manager/Principal LGO/dmf GEOTECHNICAL ENGINEERING REPORT FOSSIL CREEK NURSERY, P.U.D. FORT COLLINS, COLORADO TERRACON PROJECT NO. 20955107 July 20, 1995 Prepared for. JIM SELL DESIGN 117 EAST MOUNTAIN AVENUE FORT COLLINS, COLORADO 80524 ATTN: MR. JIM SELL lrerrocon