B. Extent of the Work: The Work specified in this Section shall include, but is not limited to, the following principal items:

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1 RIVERSIDE MEDICAL CENTER EAST EXPANSION KANKAKEE, ILLINOIS SECTION DRILLED PIERS PART 1 - GENERAL 1.01 DESCRIPTION OF WORK A. Work Included: Provide all labor, materials, equipment, transportation and other related items and services required to install drilled foundation piers for the Project, all as shown on the Drawings and as specified herein. Piers shall be end bearing on rock with an allowable service load bearing pressure of 40,000 pounds per square foot. B. Extent of the Work: The Work specified in this Section shall include, but is not limited to, the following principal items: 1. Services of a surveyor for layout and control of pier locations and elevations. 2. Drilling of piers and removal of excavated material. 3. Cooperation with the geotechnical engineer in verification of allowable bearing pressure at the base of each pier. 4. Providing reinforcing steel and dowels in the piers as shown. 5. Providing temporary and permanent steel casings to complete the Work. 6. Dewatering and cleaning of the pier excavation as required. 7. Placement and consolidation of the specified concrete to completely fill drilled pier excavation RELATED WORK SPECIFIED ELSEWHERE A. Quality Control - Section B. Earthwork - Section QUALITY ASSURANCE A. Qualifications of Workmen: Provide at lease one person who shall be present at all times during installation of drilled piers, who shall be thoroughly familiar with the codes, standards and specifications applicable to such Work, who shall have had extensive experience in the installation of drilled foundations and who shall continuously direct all Work performed under this Section. B. Codes and Standards: The Contractor shall comply with all building codes or other local, state or federal laws which pertain to this part of the Work, including those governing notices to adjacent property owner, lights and barricades, OSHA regulations and environmental protection DRILLED PIERS

2 requirements. Comply with provisions of American Concrete Institute (ACI) "Standard Specification for the Construction of End Bearing Drilled Piers" (ACI 336.1). C. Standard Specifications: The following national standard specifications as published by the American Society for Testing and Materials are referred to hereinafter and shall apply to the Work of this Section: ASTM A 252 ASTM A 444 ASTM C 31 ASTM C 33 ASTM C 39 ASTM C 42 ASTM C 94 ASTM C 143 ASTM C 150 ASTM C 172 ASTM C 192 ASTM C 231 ASTM C 260 ASTM C 494 ASTM C 617 ASTM C 618 Welded and Seamless Steel Pipe Piles Steel Sheet, Zinc-Coated (Galvanized) by the Hot Dip Process for Culverts and Underdrains Making and Curing Concrete Test Specimens in the Field Concrete Aggregates Test for Compressive Strength of Cylindrical Concrete Specimens Obtaining and Testing Drilled Cores and Sawed Beams of Concrete Ready-Mixed Concrete Test for Slump of Portland Cement Concrete Portland Cement Sampling Fresh Concrete Making and Curing Concrete Test Specimens in the Laboratory Method of Test for Air Content of freshly Mixed Concrete by the Pressure Method Air-Entraining Admixtures for Concrete Chemical Admixtures for Concrete Capping Cylindrical Concrete Specimens Fly Ash and Raw or Calcined Natural Pozzolans for Use in Portland Cement Concrete D. Testing and Inspection Services: 1. The Owner will engage and pay for the services of one or more testing service firms to provide continuous on-site inspection and testing by a qualified geotechnical engineer while drilled piers are being installed and to perform field and laboratory tests of concrete for the Work. See Section for the nature and extent of quality control activities to be performed by testing service firms. 2. The representative of the Architect/Engineer on the site may direct the testing service to perform additional inspection and/or testing procedures during installation of drilled piers if considered necessary to accomplish the purpose of these Specifications. DRILLED PIERS

3 E. Ready-Mixed Concrete: A supplier whose plant is certified by the National Ready-Mix Concrete Association shall furnish all ready-mixed concrete. The ready-mix concrete supplier shall be subject to continuing approval by the Architect/Engineer, which may be withdrawn for cause at any time. F. Surveying Services: The Contractor shall engage a registered surveyor acceptable to the Architect/Engineer to perform all surveys, layouts and measurements for drilled pier Work. The surveyor shall conduct the layout Work for each drilled pier to the lines and levels required before excavation, and he shall also perform the actual measurements of each drilled pier's horizontal axial location, shaft diameter, bottom and top elevations, deviations from specified tolerances and other data as required. The surveyor shall record and maintain all information pertinent to each drilled pier and cooperate with other testing and inspection personnel to provide data for required reports. G. Construction Tolerances: 1.04 SUBMITTALS 1. Bottom elevation of drilled piers as shown are estimated from soil boring data. The geotechnical engineer will determine the actual final bearing level during excavation. 2. Allowable dimensional tolerances for the completed piers shall be as follows: a. Concrete cut-off elevation at top of pier -- plus 1 inch to minus 3 inches. b. Horizontal variation in location of top of pier -- 1/24th of the shaft diameter or 1.25 inches, whichever is less. c. Concrete shafts out of plumb -- not more than 1.5% of the shaft length, or 12.5% of the shaft diameter or 3.75 inches, whichever is less. 3. If the tolerances specified in either Clause G.2.b. or Clause G.2.c. above are exceeded, the Contractor shall pay for redesign services performed by the Architect/Engineer, and he shall also provide and pay for any corrective construction that may be required by the Architect/Engineer based on such redesign. A. Interim Submittals: The Contractor shall submit the following items for review and/or approval, either prior to or during the course of the Work as required by the Construction Manager: 1. Reinforcing steel shop drawings. 2. Certified mill test reports for reinforcing steel. 3. A detailed written description of proposed procedures for casing removal. 4. A detailed written description of proposed procedures for placement of concrete by the tremie method, if any. 5. Surveyor's interim reports of actual location, alignment, elevations and dimensions of each drilled pier. DRILLED PIERS

4 B. Ready-Mix Delivery Tickets: 1. Maintain a record at the Project site showing date, time and place of each pour of concrete, together with ready-mix delivery tickets certifying contents of the pour. 2. Make the record available to the Architect/ Engineer for inspection upon request, and completion of the Work, deliver the record and the delivery tickets to the Architect/Engineer. C. Concrete Mix Designs: Prepare concrete mix designs proportioned by either laboratory trial batch or field experience methods, using materials to be employed on the project for each class of concrete required, and report to the Architect/Engineer the following data: 1. Complete identification of aggregate source of supply. 2. Tests of aggregates for compliance with specified requirements. 3. Scale weight of each aggregate. 4. Absorbed water in each aggregate. 5. Brand, type and composition of cement. 6. Brand, type and amount of each admixture. 7. Amounts of water used in trial mixes. 8. Proportions of each material per cu. yd. 9. Gross weight and yield per cu. yd. of trial mixtures. 10. Measured slump. 11. Measured air content. 12. Compressive strength developed at 7 days and 28 days from not less than 3 test cylinders cast for each 7- and 28-day test, and for each design mix. Submit written reports to the Architect/Engineer of each proposed mix for each type of concrete at least 15 days prior to start of Work. Do not begin concrete production until mixes have been reviewed and approved by the Architect/Engineer. D. Completion Report: The Contractor shall submit a certified Final Completion Report for each drilled pier, recording actual elevation at bottom and top, elevation of rock surfaces, final centerline location at top, variation of shaft from plumb, result of all tests performed, actual allowable bearing capacity of bottom, levelness of bottom, seepage of water, still water level (if allowed to flood), elevation of bottom and top of any casing left in place, any unusual conditions, variation of bell dimensions from original design, dates of starting excavation, completion of excavation, inspection, testing and placement of concrete (include any delays in concreting and location of construction joints in shafts), and any other data required. DRILLED PIERS

5 1.05 JOB CONDITIONS A. Condition of the Site: The Contractor shall have visited the site and carefully examined the general conditions under which his Work is to be performed prior to submitting a proposal, all as required in the General Requirements of these Specification. B. Subsurface Data: The Contractor shall consult any and all available information on subsurface conditions at the Project site. As indicated, the Owner does not represent or warrant that this available information is either accurate or complete, and the Contractor shall be totally responsible for verifying or supplementing the subsurface data to the extent that he considers necessary.. C. Existing Utilities: 1. The Contractor shall have all existing underground utilities within the building area carefully located by a qualified surveyor before starting drilled pier excavation operations. Utilities that are to remain in place shall be protected from damage during drilled pier work. 2. Should uncharted or incorrectly charted piping or other utilities be encountered during excavation, consult the Architect/Engineer immediately for directions as to procedure. Cooperate with the Owner and with public or private utility companies in keeping their respective services and facilities in operation. Repair damaged utilities to the satisfaction of the utility owner. D. Protection of Personnel on the Site: 1. The Contractor shall be fully responsible for protecting the safety of both workmen and the general public at all times while installation of drilled piers is in progress. 2. Provide and maintain all items of protection that are necessary for human safety and as may be required by authorities having jurisdiction. All unguarded open holes shall be covered with a platform constructed of two thicknesses of 2" planking at right angles to each other and secured against displacement. E. Protection of Pier Excavations: The Contractor shall protect all drilled piers during installation against surface and rainwater and against water that may enter from sides or bottom of the excavation. If quicksand, running material, water-bearing strata, or other unstable material is encountered which cannot be excluded from the excavation by means of the steel casing being used, the Contractor shall perform such work as necessary to seal off such material in a manner approved by the Architect/Engineer PRODUCT DELIVERY, HANDLING AND STORAGE A. Casings: All required temporary and/or permanent casing shall be delivered to the site in good condition and shall be handled and stored in a manner to avoid subsequent damage or deterioration. Casings shall be round within plus or minus 2% at the time of use or installation. B. Reinforcing Steel: Reinforcing steel shall be handled and stored on the site so as to avoid excessive rusting or contamination with oil or dirt, and bars shall be clean and straight when installed. C. Storage on the Site: The Contractor shall store casings and reinforcing steel on the site only where and as permitted by the Architect/Engineer and Owner, and such storage shall not be allowed to interfere with the Work of any other Subcontractor on the site. DRILLED PIERS

6 1.07 UNIT PRICE PROPOSALS The Contractor's base proposal shall assume, and the Contract Sum will be based on, the use of a temporary steel casing, a permanent corrugated steel liner and the bottom elevation of the drilled piers as shown on the Drawings. The cost for changes involving additions to or deductions from the Work shown on the Drawings, shall be computed in accordance with the applicable unit prices in the "Schedule of Unit Prices" as listed in the Proposal. The Contractor shall provide unit prices for the following units of Work: A. Permanent corrugated steel casing - per linear foot installed. B. Drilled pier excavation in clay by machine - per cubic yard. C. Removal of rock by machine - per cubic foot. D. Hand removal of rock or debris - per cubic foot. E. Reinforcing steel in place - per pound. F. Concrete in place in piers - per cubic yard. PART 2 - PRODUCTS 2.01 MATERIALS A. Concrete Materials: 1. Portland Cement: ASTM C 150, Type I for normal Portland cement, Type III for high-early strength Portland cement. 2. Aggregates: Natural washed and processed sand and gravel conforming to ASTM C Air-Entraining Admixtures: ASTM C Other Chemical Admixtures: ASTM C Fly Ash: ASTM C 618, Class F. a. Limit use of fly ash to not exceed 25% of cement content by weight. 6. Water: Clean, fresh and potable. B. Reinforcing Bars: Shall be deformed bars, Grade 60, complying with requirements of ASTM A 615, "Deformed and Plain Billet Steel Bars for Concrete Reinforcement." C. Temporary Casing: Temporary steel casings shall be furnished and used as specified herein and as shown on the Drawings. Casings shall conform to ASTM A 252, Grade 2, or shall be fabricated from ASTM A 36 steel not less than 5/8" thick. D. Permanent Casing: Permanent casing for drilled piers, shall be galvanized, corrugated steel pipe with an inside diameter equal to the design diameter of the pier as indicated on the Drawings. The material for the casing shall be of sufficient thickness to withstand compressive and displacement stresses and to maintain an open shaft of the required diameter, and it shall conform to ASTM A 444. DRILLED PIERS

7 2.02 CONCRETE MIXTURE A. Design of Concrete Mixtures: 1. Concrete mix designs shall be made on the basis of laboratory trial batches or of field experience with the material to be employed, for each type of concrete required, in accordance with the Drawings and Specifications. Strength requirements shall be as noted on Drawings. Submit all mix designs for approval by the Architect/Engineer. 2. Admixtures, other than air-entraining admixtures, shall be used in concrete only with the prior written approval of the Architect/Engineer. Admixtures shall be produced by wellestablished and reputable manufacturers and shall only be used in accordance with the manufacturer's printed directions. Calcium chloride or admixtures containing chloride salts shall not be added to concrete. 3. If at any time during construction the concrete resulting from the approval mix design proves to be unsatisfactory for any reason, such as too much water; lack of sufficient plasticity to prevent segregation, honeycomb, etc.; or insufficient strength; the Contractor shall immediately notify the Architect/Engineer who will arrange to modify the mix so that a satisfactory concrete is obtained. B. Concrete for Piers: Structural concrete to be placed in drilled piers shall be designed by the concrete supplier, subject to approval by the Architect/Engineer and subject to conformance with all building code requirements. Concrete mix designs shall also conform to the following minimum requirements: 1. Minimum 28-day compressive strength - as noted on the Drawings. 2. Minimum cement content bags per cubic yard. 3. Maximum water content gallons per bag. 4. Entrained air - 3% to 6%. 5. Slump range - 2 inches to 4 inches, except as indicated in Paragraph 3.07 D. below READY-MIXED CONCRETE A. General Requirements: 1. All ready-mixed concrete shall comply with ASTM C 94 and, in addition, shall comply with the special requirements indicated below. 2. The ready-mix concrete producer shall submit duplicate delivery ticket, one for the Contractor and one for the Architect/Engineer, with each load on concrete delivered to the site. 3. Delivery tickets shall provide the following information: a. Date of delivery. b. Name of ready-mix concrete plant. c. Trade Contractor. DRILLED PIERS

8 d. Project location. e. Type (Standard or H.E.S) and brand of cement. f. Cement content in bags per cubic yard of concrete. g. Truck number. h. Time dispatched and time unloaded. i. Amount of concrete in load in cubic yards. j. Type and maximum size of aggregate. k. Maximum allowable slump. l. Total water content expressed as water/ cement ratio. 4. Maintain equipment in proper operating condition, with drums cleaned before charging each batch. Schedule rates of delivery in order to prevent delay of placing the concrete after mixing or holding dry-mixed materials too long in the mixer before the addition of water and admixtures. B. Special Requirements: Requirements for ready-mix concrete, in addition to those in ASTM C 94, shall be as indicated below, provided the quantity and rate of delivery will permit unrestricted progress of the Work in accordance with the placement schedule. During hot weather, or under conditions contributing to rapid setting of concrete, a shorter mixing time than specified in ASTM C 94 may be required, as specified below. Proposed changes in mixing procedures, other than herein specified, must be accepted by the Architect/Engineer before implementation. 1. Plant Equipment and Facilities: Conform to National Ready-Mix Concrete Association "Checklist for Certification of Ready-Mix Concrete Production Facilities." 2. Quality of Concrete: Provide concrete materials, proportions and properties as herein specified, in lieu of ASTM Section Tolerance in Slump: Provide slump of not more than the values as herein specified, in lieu of ASTM Section 6.1. Comply with other criteria of ASTM Section Mixing and Delivery: Delete the references for allowing additional water to be added to the batch for material and insufficient slump. Addition of water to the batch will not be permitted. As specified in ASTM Section 10.7, when the air temperature is between 85 o F. and 90 o F., reduce the mixing and delivery time from 1-1/2 hours to 75 minutes, and when the air temperature is above 90 o F., reduce the mixing and delivery time to 60 minutes. 5. Use of Truck Mixer: When a truck mixer is used for the complete mixing of the concrete, begin the mixing operation within 30 minutes after the cement has been intermingled with the aggregates. 6. Strength: Delete ASTM Section 16; comply with concrete testing requirements as specified herein and in Section 01400, "Quality Control." DRILLED PIERS

9 2.04 INSTALLATION EQUIPMENT A. General: Piers shall be drilled by means of a power drive rotary bucket or auger type foundationdrilling rig. Installation equipment shall be in first-class condition and shall be so maintained and operated at all times. Equipment shall be capable of excavating shafts to depths and diameters indicated and within specified tolerances. PART 3 - EXECUTION 3.01 INSPECTION A. General: Prior to beginning the Work, the drilled pier Installer shall examine the areas and conditions under which the drilled piers are to be installed. Notify the Architect/Engineer in writing of any conditions detrimental to the proper and timely completion of the work. Do not proceed with the Work until all unsatisfactory conditions have been corrected in a manner acceptable to the drilled pier Installer DRILLED PIER EXCAVATION A. General: Excavate shafts for drilled piers to the diameter shown on the Drawings, and to depth required to reach suitable bearing material with the required bearing strength specified. Install temporary casings as excavation proceeds to maintain sidewall stability during drilling operations. B. Removal of Obstructions: If buried construction rubble, rock, boulders or other unforeseen obstructions are encountered which cannot be removed by standard excavation methods, and if such obstructions are not indicated by available subsurface data, removal of such obstructions will be paid for in accordance with the terms of the Contract relative to changes in the Work. Remove such obstructions using air-powered tools, or by other safe methods recognized in the construction industry. The term "standard excavation methods" shall include the use of core barrels with drilling equipment. C. Classification of Rock: Rock is defined as material which cannot be drilled with a conventional earth auger or under-reaming tool, and requires use of special rock augers, core barrels, air tools blasting, or other methods of hand excavation. Earth seams, rock fragments, and voids included in rock excavation area will be considered rock for all volume of shaft from initial contact with rock for pay purposes. D. Dewatering: Provide and maintain pumping equipment to keep the excavations free of water before placing concrete. If excessive water is encountered and drilling operations must be halted, consult with the Architect/Engineer before using alternate methods of construction. Conduct water to general site run-off ditches and disposal areas with sufficient discharge lines. Provide additional ditching as required to connect water to site drainage facilities. Perform pumping a manner that will not cause loss of ground that might adversely affect this structure or other structures or Work on the site. DRILLED PIERS

10 E. Excavated Material: All excavated material shall be removed from the site and legally disposed of by the Contractor INSPECTION AND TESTING A. General: The Contractor shall cooperate with the geotechnical engineer who will be engaged by the Owner to perform the inspection and testing services outlined in Section of these Specifications and further described in the balance of this Article B. Geotechnical Engineer: The geotechnical engineer will determine suitability of supporting material for drilled piers, as follows: 1. Explore bearing stratum to minimum depth equal to two times the diameter of the bearing area below the bottom of the drilled pier with probe hole. 2. Inspect and test the bottom of all piers after Contractor cleans bottom of loose material. 3. Drilling of rock socket shall proceed immediately upon confirmation of the allowable service load bearing value of the bearing stratum by the geotechnical engineer. 4. If test results indicate the bearing stratum is not capable of providing the required service load bearing pressure of 40,000 psf, notify the Architect/Engineer for a determination of adjustments to be made. These may include, but shall not necessarily be limited to, advancing the shaft length as directed by the geotechnical engineer and repeating the above steps, or enlarging the shaft diameter as determined by the Architect/Engineer for the appropriate bearing pressure as determined by the geotechnical engineer. C. Contractor Services: The Contractor shall perform the following testing services and provide the following Work as directed by the geotechnical engineer: 1. Provide gas testing equipment, protective cage or temporary casing of proper diameter, length and thickness and other safety equipment required by law for inspection and testing of drilled piers and to protect workmen during hand belling or other operations requiring by law for inspection and testing of drilled piers and to protect workmen during hand belling or other operations requiring entry into shaft. 2. Check each drilled pier for toxic and explosive gases prior to personnel entering. If gas is found, ventilate with forced air until safe for entry. 3. Remove from bottom of drilled piers loose material or free water in quantities sufficient to cause settlement or affect concrete strength as determined by the geotechnical engineer and then excavate pier bottoms to a level plane. 4. If water seepage is considered by the geotechnical engineer to be excessive for safe removal, follow procedures specified under concrete placement below TEMPORARY STEEL CASING A. General: Provide temporary steel casings for shaft and cap excavation as necessary or required. Provide casing of sufficient strength to withstand handling stresses, concrete pressure and surrounding earth and/or fluid pressures. Make diameter of excavation in relation to diameter of casing, such as to create a minimum of void space outside of casing. B. Removal of Casing: Temporary steel casings may be removed at the option of the Contractor. If temporary casing for shaft is removed during or after concreting, follow special requirements DRILLED PIERS

11 specified under Concrete Placement below. If a permanent corrugated steel casing is required, the temporary casing shall not be removed until annular space between inner corrugated casing and outer temporary casing has been filled with grout or sand PERMANENT STEEL CASING A. General: Provide galvanized, corrugated steel pipe as specified in Paragraph 2.01 D. above for permanent casing. The casing shall be of sufficient strength to withstand handling stresses and pressures from surrounding soil and water or concrete inside. Provide casings with inside clear diameter not less than the diameter of the pier shaft. B. Delivery and Handling: Corrugated casings may be delivered in any convenient section or panel, with sections or panels field-connected in accordance with the manufacturer's instructions. Install permanent steel casing as excavation work progresses and as required to ensure the stability of pier shaft walls. Remove and replace or repair casings which are damaged during installation and which could impair the strength or efficiency of the completed pier REINFORCING STEEL A. General: Furnish and place reinforcement for drilled piers as shown on the Drawings and as specified herein. Follow approved Shop Drawings in fabrication and placement of reinforcing steel for the Work. B. Condition of Reinforcement: Reinforcement at the time of placement shall be free of mud, oil or other coatings which would adversely affect bond with the concrete. C. Protection of Reinforcement: Protect exposed ends of extended reinforcing or dowels from mechanical damage and exposure to weather CONCRETE PLACEMENT A. Pre-Placement Inspection: Before any concrete is placed in piers, verify that the bottom of the pier excavation is clean and that the excavation is free of standing water. Fill each drilled pier with concrete as soon as possible after drilling is complete, but not until the completed excavation has been examined and approved by the geotechnical engineer and permanent casing has been placed. B. Timing of Placement: Place concrete as soon as possible after excavation is completed. Do not leave uncased excavations open overnight. Place concrete in piers in one continuous operation. If a construction joint is unavoidable, level, roughen and clean surface prior to recommencement of concrete placement. Provide reinforcing dowels and/or a shear key as shown or when required by the Architect/Engineer. C. Method of Placement: Free fall concrete may be used provided it is directed through a hopper, or equivalent, such that fall is vertical down center of shaft without hitting sides or reinforcing. Supports for hopper shall not project into or through the hopper. Vibrate top 5 feet of concrete, but only after casing has been pulled or when casing is permanent. D. Removal of Casing: The geotechnical engineer will provide inspection during the removal of temporary shaft casing and placing of concrete. Withdraw casing only as shaft is filled with concrete. Maintain adequate head of concrete to balance outside soil and water pressure above the bottom of the casing at all times during withdrawal. Specific procedures that the contractor will follow to accomplish this objective shall be submitted for approval. Provide specially designed concrete with a minimum slump of 5 inches and with a retarder to prevent arching of concrete (during casing pulling) or setting of concrete until after casing is pulled. Check concrete level prior to, during and after pulling casing. Avoid vibrating concrete if casing is pulled. DRILLED PIERS

12 E. Severe Weather Concreting: 1. If concrete is placed in piers during cold weather, the Work shall comply with ACI 306, "Recommended Practice for Cold Weather Concreting." 2. If concrete is placed in piers during hot weather, the Work shall comply with ACI 305, "Recommended Practice for Cold Weather Concreting." F. Grouting of Pier Liner: The Contractor shall fill the annular space outside of the casing with fluid grout by means of a grout pipe and a pressure grout pump under the supervision of the geotechnical engineer. G. Underwater Placement: Concrete may be placed in drilled pier excavations without dewatering the excavation only if absolutely unavoidable, and then only with the prior written approval of the Architect/Engineer. The Contractor's request for such approval shall be in writing and shall be accompanied by a detailed written description of the procedures to be followed in performing the Work under such circumstances. Placement shall be by tremie pipe or concrete pump, using all necessary precautions to avoid any weakness or interruption of the concrete as a result. The Architect/Engineer's approval, if granted, will be conditioned upon successful execution of the proposed procedures by the Contractor. END OF SECTION DRILLED PIERS