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Home My WebLink About990222.tiff 1 1 GEOTECHNICAL INVESTIGATION AT 5617 UTE LANE WELD COUNTY, COLORADO J Prepared For. Allen Rathe 5617 Ute Lane Greeley, Colorado 80634 September 10, 1998 Project No. RATA-8H6E-01-709 l LANDMARK ENGINEERING LTD. 3521 W. EISENHOWER BLVD. EXHIBIT LOVELAND, CO 80537 �,I] ^ 990222 Landmark ENGINEERING Ltd. - - September 10, 1998 Project No. RATA-8H6E-01-709 Mr. Allen Rathe 5617 Ute Lane Greeley, Colorado 80634 • Gentlemen: • The enclosed report presents the results of a geotechnical investigation for the proposed metal building at 5617 Ute Lane, Greeley, Colorado. If you have any questions or if we may be of further assistance, please feel free to contact our office. Sincerely, Landmark Engineering Ltd. -171 ar Miller Ge logist LAM/ej `\��p\\111111111/7777 /• �p,OO REG/ . ✓� • 6857 ' The above has bee rev#elr• and alie ied under the direct supervision of Rodney A. Harr, Colorado �:, ,5j,•.•'V��\\.� 990222 3521 West Eisenhower Blvd. Dale D. Olhausen. P.E. & L.S. Loveland, Colorado 80537 President ENGINEERS • ARCHITECTS • PLANNERS • SURVEYORS d Loveland (970) 667-6286 FAX (970) 667-6298 Denver (303) 629-7124 1i TABLE OF CONTENTS Page Letter of Transmittal Table of Contents ii Scope 1 Site Location and Description 1 Field Investigation 1 Laboratory Testing 2 Subsurface Conditions 2 Foundation Recommendations 3 Floor Slabs 6 Site Grading, Landscaping and Drainage 6 General Information 7 Location of Borings Plate 1 Legend of Soils and Rock Symbols Plate 2 Boring Logs Plates 3 - 4 Consolidation - Swell Tests Drawings 1 - 2 Suggested Specifications For Placement of Compacted Earth Fills and/or Backfills Appendix A 990222 SCOPE The following report presents the results of a geotechnical investigation at 5617 Ute Lane, Greeley, Colorado. This investigation was performed for Mr. Allen Rathe. The purpose of this investigation was to obtain technical information and subsurface property data necessary for the design and construction of foundations for the proposed 60'x 30'metal building. The conclusions and recommendations presented in this report are based upon analysis of field and laboratory data and experience with similar subsurface conditions in the general vicinity. SITE DESCRIPTION The project site is located in Southwest Greeley in Arrowhead Subdivision. The proposed metal building is to be located at the Northwest corner of the lot. An existing house is located near the center of the parcel. Topographically, the site slopes slightly to the South at less than 2%. 1 FIELD INVESTIGATION This field investigation consisted of two (2) borings at selected locations on the site. The borings were advanced with an Acker AD-II drill rig utilizing 4-inch diameter continuous flight augers. As the boring operation advanced, an index of soils relative density and consistency was obtained by use of the standard penetration test, ASTM Standard Test D-1586. The penetration test result listed on the log is the number of blows required to drive the 2 inch split-spoon sampler twelve inches, or increments as shown, into undisturbed soil bya 140- pound hammer dropped 30 inches. 1 990222 7 Undisturbed samples for use in the laboratory were taken in 3" O.D. thin wall samplers (Shelby), pushed hydraulically into the soil and 2.5" O.D. California saniplers driven into the soil. Undisturbed and disturbed samples were sealed in the field and preserved at natural moisture content until time of test. Complete logs of the boring operation are shown on the attached plates and include visual classifications of each soil, location of subsurface changes, standard penetration test results, and subsurface water level measurements at the time of this investigation. LABORATORY TESTING The laboratory testing program was undertaken to determine visual classification,moisture contents, dry densities, swelling and consolidation characteristics, and soluble sulfates. SUBSURFACE CONDITIONS Subsurface soils were relatively uniform consisting of silty sands overlying weathered claystone and sandstone bedrock. A description of each in order of increasing depth follows. Silty Sand-At the surface in both borings and extending to depths of 3 to 5 feet, a firm, dry clay with silty sand was encountered. Laboratory and field data collected indicates this material offers low to moderate bearing capacities while possessing consolidation properties when wetted. Claystone - Below the sands a weathered, tan to gray colored claystone was found. Laboratory tests indicate this material exhibits moderate bearing capacities while possessing moderate to high swell potentials when subjected to wet loading. 2 990222 Sandstone - Below the claystone and extending to depths explored a dense, poorly cemented to uncemented silty sandstone was encountered. Test data shows this material offers high bearing capacities with no swell potentials. Groundwater-At depths of 13 and 12-1/2 feet, free groundwater was noted in Boring No.'s 1 and 2 respectively. These groundwater levels do not necessarily indicate high levels, and they should be anticipated to fluctuate throughout the seasons. FOUNDATION RECOMMENDATIONS The selection of the foundation type fora given situation and structure is governed by two basic considerations. First, the foundation must be designed so as to be safe against shear failure in the underlying soils, and second, differential settlement or other vertical movement of the foundation must be controlled at a reasonable level. Two basic controls are available to us in selecting the foundation type and allowable loads. These are the standard penetration test and consolidation-swell testing. The ultimate bearing capacity of the foundation soil depends upon the size and shape of the foundation element, the depth below the surface, and the physical characteristics of the'supporting soil. Drilled Pier(Caisson) and Grade Beam Foundations Due to the expansive nature of the claystone bedrock, the foundation should be a drilled pier(caisson) and grade beam foundation. The piers should be designed for a maximum end bearing of 20,000 pounds per square foot (dead load plus full live load), and side shear of 1,000 pounds per square foot for that portion bearing in the firm uncemented sandstone, and a minimum dead load of 8,000 pounds per square foot. 3 990222 Difficulty is sometimes experienced in achieving the desired minimum dead load. If this occurs, we suggest the piers be reinforced full length to take the difference between the "desired"and the "obtainable"dead load in tension. One half(%) of the side shear value given above maybe used in uplift provided the sides of the hole are grooved or roughened. In drilling the piers the following design and construction details should be observed. 1. Piers should be designed for the maximum end bearing pressure and skin friction specified in this report. 2. All piers should be designed for the minimum dead load pressure specified in this report. 3. All piers should penetrate a minimum of 4 feet into the firm sandstone bedrock stratum with a minimum length of ten feet (10') and a minimum diameter of twelve inches (12'). 4. All piers should be reinforced for their full length to resist tension. We recommend the use of at least two (2) Grade 60, #5 bars for 12"diameter piers. For larger piers, the area of reinforcing shall be equal to or greater than 0.5 percent of the gross cross-sectioned area of the pier. 5. A minimum of 4 inch air space should be provided beneath all grade beams to insure the concentration of dead load pressure on the piers. 6. All piers should be carefully cleaned and dewatered before placing concrete. In our opinion, casing and/or dewatering probably will not be required. 7. Most of the bedrock at the site can be drilled with normal heavy commercial size pier drilling rig. Some of the bedrock is very hard and a problem may arise if the 4 990222 contractor attempts to drill the pier holes with small drill rigs. In case drilling refusal is encountered, the depth of penetration into firm bedrock maybe reduced if design criteria are adjusted accordingly. 8. All pier holes should be inspected during construction by a competent soils engineer or technician to insure that penetration is started at the proper depth and no loose material remains in the holes. 9. Concrete should be placed into the pier holes immediately after drilling. The following recommendations should be followed in the design of the foundation system: 1. All caissons should bear in the uncemented sandstone bedrock. 2. Partition walls should not be placed directly on concrete slabs. They should be hung from the floor joists, or other approved method which will allow the slab to heave unimpaired for a vertical distance of 1-1/2 inches. Foundations shall be provided for all bearing walls. • 3. Laboratory test results indicate that soluble sulfates are 150 parts per million. Therefore, a Type I-Il cement should be used for all concrete exposed to the soils or rock. 4. The bottom of all foundation components (except piers) should be placed at least three feet (3') above subsurface water levels. 5. The completed open excavation should be inspected by an experienced soils engineer or technician to confirm the subsurface conditions described in this report and observe any variations which may affect construction at the site. 5 990222 FLOOR SLABS The slabs placed on the natural ground at the site should be anticipated to heave or settle to some degree due to swelling or consolidating of the subsoils. Therefore, slabs should be constructed to be "free-floating", isolated from all bearing members, utilities, and partitions so that the slab can move unimpaired without producing architectural or structural damage. Slabs should be placed directly on undisturbed soil, underlain with a four-inch (4') layer of washed rock to help distribute floor loads, provide a capillary break, and provide a pathway for potential infiltrating water to be directed toward sump areas. If moisture sensitive floor coverings are used on interior slabs, consideration should be given to the use of barriers to minimize moisture rise through the slab. Positive drainage should be provided for the excavation subgrade to prevent pooling of water beneath the slab. The slabs should be reinforced with wire mesh, or equivalent. The slabs should be jointed to a depth of at least one-quarter (1/4) of the slab thickness in dimensions not to exceed fifteen feet (15') or 225 square feet and at areas of potential cracking. Exterior slabs exposed to de-icing chemicals or extreme weathering should be constructed using Type II cement with higher air contents and higher compressive strengths. SITE GRADING, LANDSCAPING & DRAINAGE Every precaution should be taken to prevent wetting of the subsoils and/or rock and percolation of water down along the foundation elements. Water infiltrating along side the foundation may result in architectural or structural damage due to weathering or swelling at the subsoils and/or rock. Backfill around the outside perimeter of the structure should be compacted at optimum moisture, or above, to at least 90 percent of Standard Proctor Density as determined by ASTM Standard Test D-698. A suggested specification for placement of backfills is included as Appendix A. Backfill material should be relatively impervious and non-swelling. The backfill should be free of frozen soil, large dried clods, and organic matter. Backfilling should only be accomplished when concrete strength and 6 990222 adequate support to foundation walls are applied and acceptable to the Foundation Engineer. It is our opinion that the natural soils at the site could be used for backfill material. Finished grades should be sloped away from the structure on all sides to give positive drainage. A minimum of 6 inches fall in the first 10 feet is recommended and should be maintained throughout the life of the structure. Sprinkling systems should not be installed within 10 feet of the structure. Downspouts are recommended and should be arranged to carry drainage from the roof at least 5 feet beyond the foundation walls. Should landscaping plants be located next to the structure, we recommend the use of varieties of plant life which require little watering. GENERAL INFORMATION The data presented herein were collected to help develop designs and cost estimates for this project. Professional judgements on design alternatives and criteria are presented in this report. These are based on evaluation of technical information gathered, partly on our understanding of the characteristics of the proposed metal building. We do not guarantee the performance of the project in any respect, only that our engineering work and judgements rendered meet the standard of care of our profession. The test holes drilled were spaced to obtain a reasonably accurate picture of subsurface conditions for design purposes. Variations from the conditions portrayed frequently occur. These variations are sometimes sufficient to necessitate modifications in design. We recommend that construction be continuously observed by a qualified soils technician trained and experienced in the field to take advantage of all opportunities to recognize different conditions and minimize the risk of having some undetected condition which might affect the performance of the foundation elements. 990222 17 IN fRoPosco 0-/ MET/4“ 8 Z RLD4. I 1 1 Nousc i 1 ure i_ ANE 990222 Plate 1 nilan UWJmoII U W TITLE: Soi� �jOR��JU S�TL IRAN �i ¢war RIIID�Gq®�.Om. p ENGINEERS/ARCHITECTS/PLANNERS/SURVEYORS CLIENT: j4 LLEN R -r-r+e 1521 West Eisenhower Blvd., Lovolond, Colorado 80537 (970) 667-6266 Denver (303) 629-7124 Fox (970) 667-6296 SCALE: I ": 4/v I DATE: 9--3-78 I PROJ. ,PpiA 8/16E al 7ei LEGEND OF SOIL AND ROCK SYMBOLS FILL MATERIAL Depth Below Surface o,a. . • ;o^� GRAVELS (GW,GP,GM,GC) Dv.oWater Level SANDS(SW,SRSM,SC) 5 After 24 Hours ••; \ SILTS ( ML,MH ) • t CLAYS(CL,CH,OL,OH NNN NNN ORGANICS 10 \ Shelby Thin-walled Sampler "" II -1 —'- BEDROCK \ Split-spoon Sampler * \ • CLAYSTONE & SHALE \ Q California Sampler --- 15 \\ • SILTSTONE `. SANDSTONE �� ) � \ Bag Sample ); r LIMESTONE 20 '. ;':'; IGNEOUS/ METAMORPHIC '.'. ROCKS SYMBOLS COMBINED * Split-spoon sample utilizes a TO REPRESENT SOIL (40 lb. hammer dropping 30", MIXTURES Recording number of blows Example: per 12" or partial increment. vim, (ASTM D1586) SILTY CLAY +a GRAVELLY CLAY 990222 ® LandmarkPLATE LABORATORIES Ltd. NO. 2 3521 west Eisenhower Blvd..Loveland.Colorado 60537(303)667-6266•Greeley(303)356-6286•Denver(303)629-7124 LOG OF BORING BORING NO. CLIENT: Allen Rathe DRILL RIG: Acker AD-II 1 PROJECT NO: RATA 8H6E 01 709 ROD SIZE: AW PROJECT LOCATION: 5617 Ute Lane METHOD OF DRILLING: 4"S.S. DRILLER: LAM DATE DRILLED: 9/02/98 ENGINEER/GEOLOGIST: LAM ELEVATION: natural grade WEATHER: sunny,70 deg. F L w `� w DESCRIPTION w w z Z, REMARKS m a w w 1— or w >- < o 0 < OZ } U 0 v) CO Cl) j 3 2 OU o m -v - • silty sand,firm, dry-damp,It. brn.- - brn 2.8 97.8 -5- 11/12 - claystone w/interlayered sands, - weathered,v.stiff-hard,gray-tan - 50/7 8.1 99.4 - -10- 7L weathered silty sandstone, poorly - cemented, sl. clayey, moist-wet, - -_ tan-rust - —_ — water @ 13' - -15- -_.-Z 50/5 20.6 - -20 -25- -30- -35- -40- PLATE 3 - tLandmarN LABORATORIES, LTD. 990222 LOG OF BORING BORING NO. CLIENT: Allen Rathe DRILL RIG: Acker AD-II 2 PROJECT NO: RATA 8H6E 01 709 ROD SIZE: AW — PROJECT LOCATION:-5617 Ute Lane - METHOD OF DRILLING: 4"S.S. DRILLER: LAM DATE DRILLED: 9/02/98 ENGINEER/GEOLOGIST: LAM ELEVATION: natural grade WEATHER: sunny,70 deg. F J W JO w DESCRIPTION w wZ REMARKS n. 2 2 I— U r COz > LL CC U a CO CO U) UU 0 a ("et( silty sand,firm, dry-damp, It. brn.- brn 2.8 1_,14/12 12.3 114.5 - -5- —30/12 - •— — claystone w/interlayered sands,• - - — _I 50/11 weathered,v. stiff-hard,gray-tan 9.7 10- _ _ weathered silty sandstone, poorly cemented,sl.clayey, moist-wet, - - - tan-rust water @ 12.5' - -15- — - I - -20- - -25- - -30- - -35- - -40- - PLATE 4 - tLandmarh LABORATORIES, LTD. 990222 SWEL .- CONSOLIDATION --EST 2 Test Hole No. 1 I Oa J `-N Depth (Ft.) 2; W )water added -2 _4 Z O - Q —6 C O _8 U) Z O U 0A 1 10 100 LOAD (KSF) SOIL TYPE, silty sand NAT. MOISTURE' 2.8 0/0 NAT. DRY DENSITY ' 97.8 PCF 2 1 Test Hole No. 1 J -J Depth (Ft.) 71 02 id C.° Z -1 O Qwater added 0 -L O v) Z O U 1 0.1 1 10 100 LOAD (KSF) SOIL TYPE' uncemented silty NAT. MOISTURE ' 8. 1 '/o sandstone NAT. DRY DENSITY : 99.4 PCF Landmark Client Allen Rathe Drawing No. Job No.: 1 LABORATORIES LTO. RATA 8H6E 01 709 940222 SWEL! • CONSOLIDATION " EST 8 _ 6 Test Hole No. 2 J Depth (Ft.) 41 4 \a 0 2 Z 0 - Q o. a j J � O _2 water added-' d U 0.1 1 LOAD (KSF) 10 100 SOIL TYPE ' weathered claystone NAT. MOISTURE: 12.3 0/0 NAT. DRY DENSITY = 114.5 PCF ITest Hole No. -J 1 J Depth (Ft.) 0 0 z 0 C 0 co Z 0 U Il 01 1 LOAD (KSF) 10 100 SOIL TYPE: NAT. MOISTURE ' % NAT. DRY DENSITY = PCF Client= Allen Rathe Drawing No.: Landmark Job No.: 2 LABORATORIES LTD. RATA 8H6E 01 709 9902 a2 APPENDIX 'A' Suggested Specifications for Placement of Compacted Earth Fills and/or Backfills. GENERAL A Soils Engineer shall be the owner's representative to supervise and control all compacted fill and/or compacted backfill placed on the project. The soils engineer shall approve all earth materials prior to their use, the methods of placing, and the degree of compaction obtained. A certificate of approval from the soils engineer will be required prior to the owner's final acceptance of the filling operations. MATERIALS The soils used for compacted fill beneath interior floor slabs and backfill around foundation walls shall be non-swelling for the depth shown on the drawings or as recommended in this report. No material shall be placed in the fill having a maximum dimension of six inches or greater. All materials used in either compacted fill or compacted backfill shall be onsite materials or shall be subject to the approval of the soils engineer. PREPARATION OF SUBGRADE All topsoil and vegetation shall be removed to a depth satisfactory to the soils engineer before beginning preparation of the subgrade. The subgrade surface of the area to be filled shall be scarified to a minimum depth of six inches, moistened as necessary, and compacted in a manner specified below for the subsequent layers of fill. Fill shall not be placed on frozen or muddy ground. 1 990222 PLACING FILL No sod, brush, frozen material or other deleterious or unsuitable material shall be placed in the fill. Distribution of material in the fill shall be such as to preclude the formation of lenses of material differing from the surrounding material. The materials shall be delivered to and spread on the fill surface in such a manner as will result in a uniformly compacted fill. Prior to compacting, each layer shall have a maximum thickness of eight inches; and its upper surface shall be approximately horizontal. MOISTURE CONTROL The fill material in each layer, while being compacted, shall as nearly as practical contain the amount of moisture required for optimum compaction; and the moisture shall be uniform throughout the fill. The contractor may be required to add necessary moisture to the backfill material, in the excavation if, in the opinion of the soils engineer, it is not possible to obtain uniform moisture content by adding water on the fill surface. If, in the opinion of the soils engineer, the material proposed for use in the compacted fill is too wet to allow adequate compaction, it shall be dried in an acceptable manner prior to placement and compaction. COMPACTION When an acceptable, uniform moisture content is obtained, each layer shall be compacted by a method acceptable to the soils engineer and as specified in the foregoing report as determined by the Standard Proctor Test(ASTM 698). Compaction shall be performed by rolling with approved tamping rollers, pneumatic tired rollers, three-wheel rollers, or other approved equipment well suited to the soil being compacted. If a sheepsfoot roller is used, it shall be provided with cleaner bars so attached as to prevent the accumulation of 2 990222 • 1 material between the tamper feet. The rollers should be so designed that the effective weight can be increased. MOISTURE DENSITY DETERMINATION Samples of representative fill materials to be placed shall be furnished by the contractor to the soils engineer for determination of maximum density and optimum moisture for these materials. Tests for this determination will be made using methods conforming to requirements of ASTM D 698. Copies of the results of these tests will be furnished to the contractor. These test results shall be the basis of control for compaction effort. DENSITY TESTS The density and moisture content of each layer of compacted fill will be determined by the soils engineer in accordance with ASTM D1556, D2167 or D2922. Any material found to not comply with the minimum specified density shall be recompacted until the required density is obtained. The results of all density tests will be furnished to both the owner and the contractor by the soils engineer. • 990222 Hello