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4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Decompression Deep component Deep draft waterways Deformed reinforcement Design lane Design load Design strength Design water depth Development length Deviation saddle Distortion Dolphin Duct Durability Dynamic load allowance Edge distance Effective depth Effective prestress Elastic shortening of concrete Embedment Embedment length End anchorage End block The stage at which the compressive stresses, induced by prestress, are overcome by the tensile stresses Components in which the distance from the point of 0.0 shear to the face of the support is less than 2d, or components in which a load causing more than one-third of the shear at a support is closer than 2d from the face of the support A navigable waterway used by merchant ships with loaded drafts of 14-60 ft Deformed reinforcing bars, deformed wire, welded smooth wire fabric, and welded deformed wire fabric A notional traffic lane positioned transversely on the roadway All applicable loads and forces or their related internal moments and forces used to proportion members For design by SERVICE LOAD DESIGN, design load refers to loads without load factors For design by STRENGTH DESIGN METHOD, design load refers to loads multiplied by appropriate load factors Nominal strength multiplied by a strength reduction factor, φ Depth of water at mean high water Length of embedded reinforcement required to develop the design strength of the reinforcement at a critical section A concrete block built-out in a web, flange or web-flange junction, cast monolithically with the segment, to control the geometry of, or to provide a means for changing direction of external tendons Change in structural geometry Protective object, which may have its own fender system, usually circular in plan, and structurally independent from the bridge Hole or void formed in a prestressed concrete member to accommodate a tendon for post-tensioning The ability of concrete to resist weathering action, chemical attack, abrasion and other conditions of service An increase in the applied static force effects to account for the dynamic interaction between the bridge and moving vehicles The minimum distance between the centerline of reinforcement or other embedded elements and the edge of the concrete The depth of a component effective in resisting flexural or shear forces; as for d and dv Stress remaining in concrete due to prestressing after all calculated losses have been deducted, excluding effects of superimposed loads and weight of member; stress remaining in prestressing tendons after all losses have occurred excluding effects of dead load and superimposed load Shortening of member caused by application of forces induced by prestressing An object, usually metal, plastic or wood, intentionally cast into concrete and used to lift the member, provide a hole or sleeve in the member, or to make a welded or bolted attachment to the member The length of reinforcement or anchorage provided beyond a critical section over which transfer of force between concrete and reinforcement may occur Length of reinforcement, or mechanical anchor, or hook, or combination thereof, beyond point of zero stress in reinforcement; mechanical device to transmit prestressing force to concrete in a post-tensioned member Enlarged end section of a member designed to reduce anchorage stresses OCT 97 4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Equivalent fluid Exposed External tendon Extreme Factored load Fatigue strength Fender Fiber reinforced plastic reinforcement Finite element method Flexible duct Fly ash Force effects Form Frazil ice Friction (post-tensioning) General zone Girder Global Grillage analysis method Grout Grout opening (vent) Heat of hydration High performance concrete A notional substance whose density is such that it would exert the same pressure as the soil it is seen to replace for computational purposes A condition in which a portion of a bridge's substructure or superstructure is subject to physical contact by any portion of a colliding vessel's bow, deckhouse or mast A post-tensioning tendon placed outside of the body of concrete, usually inside a box girder A maximum or a minimum Load, multiplied by appropriate load factors, used to proportion members by the strength design method The greatest stress which can be sustained for a given number of stress cycles without failure Protection hardware attached to the structural component to be protected, or used to delineate channels or to redirect aberrant vessels Reinforcement made with a resin matrix containing continuous fibers that work together as a single element A method of analysis in which a structure is discretized into elements connected at nodes, the shape of the element displacement field is assumed, partial or complete compatibility is maintained among the element interfaces, and nodal displacements are determined by using energy variational principles or equilibrium methods A loosely interlocked duct which can be coiled into a 4.0 ft diameter without damage The finely divided residue resulting from the combustion of ground or powdered coal and which is transported from the firebox through the boiler by flue gases A deformation or a stress resultant, i.e., thrust, shear, torque and/or moment, caused by applied loads, imposed deformations or volumetric changes A mold into which fresh concrete is placed to fabricate a specified shape Ice resulting from turbulent water flow Surface resistance between tendon and duct in contact during tensioning (also, see Curvature friction) Region adjacent to a post-tensioning anchorage within which the prestressing force spreads out to an essentially linear stress distribution over the cross-section of the component The main longitudinal superstructural element The term is used primarily for I- and box-section bridges of relatively long span; used interchangeably with stringer or beam Pertinent to the entire superstructure or to the whole bridge A method of analysis in which all or part of the superstructure is discretized into orthotropic components that represent the characteristics of the structure A mixture of cementitious material and water, with or without aggregate, proportioned to produce a consistency without segregation of the constituents The consistency may range from that required for pouring to that required for dry packing Inlet, outlet, vent, or drain in post-tensioning duct for grout, water, or air Heat evolved by chemical reactions with water, such as that evolved during the setting and hardening of portland cement, or the difference between the heat of solution of dry cement and that of partially hydrated cement Concrete that meets special performance and uniformity requirements including: ease of placement and consolidation without affecting strength; long-term mechanical properties; early high strength; toughness; volume stability; and, longer life in severe environments OCT 97 4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Honeycomb Influence surface Intermediate anchorage Internal tendon Isotropic reinforcement Jacking (at jacking) Jacking force Knot Lane live load Launching bearing Launching nose Lever rule Lightweight concrete Liquefaction Load Load factor Loading (at loading) Local Local zone Loss of prestress Low-relaxation steel Method of analysis Voided or unsound area of concrete resembling the cellular structure of a honeycomb May exist at the face of formed surfaces or internally and is caused by incomplete vibration or consolidation often in combination with restrictions to the placement of concrete caused by the close spacing of reinforcement or other obstructions A continuous or discretized function over a bridge deck whose value at a point, multiplied by a load acting normal to the deck at that point, yields the force effect being sought Anchorage not located at the end surface of a member or segment for tendons that not extend over the entire length of the member or segment; usually in the form of embedded anchors, blisters, ribs, or recess pockets A post-tensioning tendon placed within the body of concrete An arrangement of reinforcement in which the bars are orthogonal and the reinforcement ratios in the two directions are equal Tensioning of the prestressing tendons; at the time of tensioning The force exerted by the device, which introduces tension into the prestressing tendons A velocity of 1.1508 mph The combination of tandem axle and uniformly distributed loads, or the combination of the design truck and design uniformly distributed load Temporary bearings with low friction characteristics used for construction of bridges by the segmental launching method Temporary steel assembly attached to the front of an incrementally launched bridge to reduce superstructure force effects during launching The statical summation of moments about one point to calculate the reaction at a second point Concrete containing lightweight aggregate and having an air-dry unit weight not exceeding 135 pcf, as determined by ASTM C-567 The loss of shear strength in a saturated soil due to excess hydrostatic pressure In saturated, cohesionless soils, such a strength loss can result from loads that are applied instantaneously or cyclically, particularly in loose fine to medium sands that are uniformly graded The effect of acceleration, including that due to gravity, imposed deformation or volumetric change A coefficient expressing the probability of variations in the nominal load for the expected service life of the bridge The time when loads are applied Such loads include prestressing forces and permanent loads, but generally not live loads; refers to the maturity of the concrete at the time of loading Pertinent to a component or subassembly or components The volume of concrete surrounding and immediately ahead of the anchorage device, subjected to high compressive stresses Reduction in prestressing force resulting from combined effects of strains in concrete and steel, including effects of elastic shortening, creep and shrinkage of concrete, relaxation of steel stress, and for post-tensioned members, friction and anchorage seating Prestressing strand in which the steel relaxation losses have been substantially reduced by stretching at an elevated temperature during manufacture A mathematical process by which structural deformations, forces and stresses are determined OCT 97 4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Mode of vibration Modulus of elasticity Modulus of rupture Multi-beam bridge deck Navigable waterway Node Nominal load Nominal strength Normally consolidated soil Normal-weight concrete Orthotropic Overconsolidated soil Overconsolidation ratio Overlay Partially debonded strand Partially prestressed concrete Passive earth pressure Permanent loads Permeability Permit vehicle Plain reinforcement Post-tensioning Post-tensioning duct A shape of dynamic deformation associated with a frequency of vibration The ratio of uniaxial normal stress to corresponding strain for tensile or compressive stress below the proportional limit of a material A measure of the ultimate load-carrying capacity of a plain concrete beam and sometimes referred to as rupture modulus or rupture strength It is calculated as the apparent tensile stress in the extreme fiber of a test specimen under the load which produces rupture A bridge constructed with precast, prestressed concrete beams that are placed side-byside on the supports A waterway, determined by the U.S Coast Guard as being suitable for interstate or foreign commerce, as described in 33CFR205-25 A point where finite elements or grid components meet; in conjunction with finite differences, a point where the governing differential equations are satisfied An arbitrarily selected design load level Strength of a member or cross-section calculated in accordance with provisions and assumptions of the STRENGTH DESIGN METHOD before application of any strength reduction factors A soil for which the current overburden pressure is the greatest that has been experienced Concrete having a weight between 135 and 160 pcf Perpendicular to each other; having physical properties which differ in two or more orthogonal directions A soil which has been under greater overburden pressure than currently exists OCR equals Maximum Preconsolidation Pressure divided by Overburden Pressure A layer of portland cement or asphaltic concrete placed on a new or existing bridge deck or roadway and used as a wearing or leveling course or both Portland cement concrete overlays may be non-composite or bonded to the underlying deck, with or without connecting reinforcement, to increase the structural depth and capacity of the section A prestressing strand that is bonded for a portion of its length and intentionally debonded elsewhere through the use of mechanical or chemical means Also called shielded or blanketed strand Concrete with a combination of tensioned prestressing strands and reinforcing bars Lateral pressure resulting from the earth resisting the lateral movement of a structure or component into the soil mass Loads and forces which are, or assumed to be, constant upon completion of construction The ability of concrete to resist penetration of liquids and gases Any vehicle whose right to travel is administratively restricted in any way due to its weight or size Reinforcement that does not conform to the definition of deformed reinforcement A method of prestressing concrete whereby the tendon is kept from bonding to the plastic (wet) concrete, then elongated and anchored directly against the hardened concrete, imparting stresses through end bearing A form device used to provide a path for post-tensioning tendons or bars in hardened concrete The following types are in general use: see flexible, rigid, semi-rigid duct OCT 97 4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Pozzolan Precast members Precompressed zone Prestressed concrete Prestressing steel Pretensioning Quality assurance Quality control Radiant heat curing Reinforcement Relaxation (of tendon stress) Release strength (prestress release, prestress release strength) Reliability index Required strength Rigid duct (post-tensioning) Roadway width Sand-lightweight concrete Segmental component Semi-rigid duct (post-tensioning) Service load Setting temperature Shallow draft waterways A siliceous or siliceous and aluminous material, which in itself possesses little or no cementitious value in finely divided form and in the presence of moisture, chemically reacts with calcium hydroxide at ordinary temperatures to form compounds possessing cementitious properties Concrete elements cast in a location other than their final position Portion of flexural member cross-section compressed by prestressing force Reinforced concrete in which internal stresses have been introduced to reduce potential tensile stresses in concrete resulting from loads High strength steel used to prestress concrete and consisting of seven-wire strands, single wires, bars, rods, or groups of wires or strands A method of prestressing concrete whereby the tendons are elongated, anchored while the concrete in the member is cast, and released when the concrete is strong enough to receive the forces from the tendon through bond Actions taken by an owner or his representative to provide assurance that what is being done and what is being provided are in accordance with the applicable standards of good practice for the work Actions taken by a manufacturer or contractor to provide control over what is being done and what is being provided so that the applicable standards of good practice for the work are followed Curing of concrete, mortar, grout or neat cement paste at an elevated temperature using heat applied by means of pipes circulating steam, oil or hot water, by electric blankets or heating elements or by circulating warm air Bats, wires, strands, or other slender members, which are embedded in concrete in such a manner that they and the concrete act together in resisting forces Time-dependent reduction of stress in prestressing tendon at constant strain The strength of concrete when the strands are “detensioned” in pretensioned members A quantitative assessment of safety expressed as the ratio of the difference between the mean resistance and mean force effect to the combined standard deviation of resistance and force effect Strength of a member or cross-section required to resist factored loads or related internal moments and forces in such combinations as are stipulated in Article 3.22 Seamless tubing stiff enough to limit the deflection of a 20.0 ft length supported at its ends to not more than 1.0 in Clear space between barriers and/or curbs A class of lightweight concrete containing lightweight coarse aggregate and natural sand fine aggregate A component made up of individual elements, either precast or cast-in-place and post-tensioned together to act as a monolithic unit under loads A corrugated duct of metal or plastic sufficiently stiff to be regarded as not coilable into conventional shipping coils without damage Loads without load factors An average temperature for the structure used to determine the dimensions of a structure when a component is added or set in place A navigable waterway used primarily by barge vessels with loaded drafts of less than 9-10 ft OCT 97 4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Shear friction Shear lag Shrinkage of concrete Skew angle Slab Spacing of beams Special anchorage device Specified strength of concrete Splice Spiral reinforcement Splitting tensile strength Spread box beams Steam curing Stirrups or ties Stress range Stringer Structural mass concrete Structurally continuous barrier Strut-and-tie model Substructure Sulfate attack Superstructure A recognized concept used in the design of areas with shear forces that achieves ductility by placing reinforcement across an anticipated crack so that the tension developed by the reinforcing bars will provide a force normal to the crack This normal force in combination with “friction” at the crack interface provides the shear resistance Nonuniform distribution of stress over the cross-section Time-dependent deformation of concrete caused by drying and chemical changes (hydration process) Smaller angle between the centerline of a support and a line normal to the roadway centerline A component having a width of at least four times its effective depth The center-to-center distance between beams Anchorage device whose adequacy should be proven in a standardized acceptance test Most multi-plane anchorages and all bond anchorages are Special Anchorage Devices The nominal compressive strength of concrete specified for the work and assumed for design and analysis of new structures Connection of one reinforcing bar to another by lapping, welding, mechanical couplers or other means; connection of welded wire reinforcement by lapping; connection of a length of prestressing strand to another using special chucks; connection of piles by mechanical couplers Continuously wound reinforcement in the form of a cylindrical or rectangular helix The tensile strength of concrete, determined by a splitting test made in accordance with ASTM C496 Precast, prestressed concrete box beams that are placed on the substructure with a space between them that requires a formed structural topping (deck slab) Curing of concrete, mortar, grout or neat-cement paste in water vapor at atmospheric pressure and at a maximum temperature between about 100 F and 200 F Lateral reinforcement formed of individual units, open or closed, or of continuously wound reinforcement The term “stirrups” is usually applied to lateral reinforcement in horizontal members and the term “ties” to those in vertical members The algebraic difference between the maximum and minimum stresses due to transient loads A bridge superstructure element which is repeated in the superstructure, primarily in the longitudinal direction but occasionally in the transverse direction; used interchangeably with beam or girder Any large volume of concrete where special materials or procedures are required to cope with the generation of heat of hydration and attendant volume change to minimize cracking or concrete degradation A barrier, or any part thereof, which is interrupted only at deck points A model used principally in regions of concentrated forces and geometric discontinuities to determine concrete proportions and reinforcement quantities and patterns based on assumed compression struts in the concrete, tensile ties in the reinforcement and the geometry of nodes at their points of intersection Structural parts of the bridge, which support the horizontal span Either a chemical or a physical reaction or both between sulfates usually in soil or ground water and concrete or mortar; the chemical reaction is primarily with calcium aluminate hydrates in the cement-paste matrix, often causing deterioration Structural parts of the bridge, which provide the horizontal span OCT 97 4739 Bridge Manual APPENDIX E 6/30/03 PCI BRIDGE DESIGN MANUAL 3:41 PM Page APPENDIX E BRIDGE DESIGN MANUAL GLOSSARY Surcharge Tandem Temperature Gradient Tendon Tension tie member Thermal expansion Ties Ton (short) Tonne (metric) Transfer (at transfer) Transfer length Transverse reinforcement Type A joints Type B joints Vent Wall friction angle Water-cement ratio Water-cementitious materials ratio Welded wire reinforcement Wheel Wheel line Wheel load Wobble friction Workability Wrapping or sheathing Yield strength A load used to model the weight of earth fill or other loads applied to the top of the retained material Two closely spaced axles usually connected to the same under-carriage which enhances the equalization of load between the axles Variation of temperature of the concrete throughout the cross-section A tensioned element, generally high-strength steel wires, strands, or bars, used to impart prestress to the concrete In post-tensioned concrete, the complete assembly of prestressing steel, anchorages and sheathing, when required, is also called a tendon Member having an axial tensile force sufficient to create tension over the entire crosssection and having limited concrete cover on all sides Examples include: arch ties, hangers carrying load to an overhead supporting structure, and main tension elements in a truss See Coefficient of thermal expansion See Stirrups 2,000 lb (U.S measure) 2,205 lb Act of transferring stress in prestressing tendons from jacks or pretensioning bed to concrete member; immediately after the transfer of prestressing force to the concrete Length over which prestressing force is transferred to concrete by bond in pretensioned members Reinforcement used to resist shear, torsion, and lateral forces or provide confinement of concrete in a structural member The terms “stirrups” and “web reinforcement” are usually applied to transverse reinforcement in flexural members and the terms “ties”, “hoops” and “spirals” are applied to transverse reinforcement in compression members Cast-in-place joints of wet concrete and/or epoxy between precast units Dry joints between precast units See Grout opening An angle whose arctangent represents the apparent friction between a wall and a soil mass The ratio of the amount of water, exclusive only of that absorbed by the aggregates, to the amount of cement in a concrete, mortar, grout, or cement paste mixture; preferably stated as a decimal by mass and abbreviated w/c The ratio of the amount of water, exclusive only of that absorbed by the aggregate, to the amount of cementitious materials in a concrete or mortar mixture A series of longitudinal and transverse wires arranged substantially at right angles to each other and welded together at all points of intersection Single or dual tire at one end of an axle A transverse or longitudinal grouping of wheels One-half of a specified design axle load Friction caused by unintended deviation of prestressing sheath or duct from its specified profile or alignment That property of freshly mixed concrete or mortar which determines the ease with which it can be mixed, placed, consolidated and finished Enclosure around a prestressing tendon to avoid temporary or permanent bond between prestressing tendon and surrounding concrete The specified yield strength of reinforcement OCT 97 5970 Bridge Manual APPENDIX F 9/21/01 PCI BRIDGE DESIGN MANUAL 11:11 AM Page APPENDIX F PCI CERTIFICATION PROGRAMS INTRODUCTION Since 1967, the Precast/Prestressed Concrete Institute (PCI) has been a leader in the development of innovative quality programs It was 1967 that saw the beginning of the PCI Plant Certification Program, a program that would set the pace for other construction-related certification programs that followed in later years (Duggleby, 1992) In 1985, PCI implemented its Plant Quality Personnel Certification Program and in 1999, introduced the Certified Field Auditor and Field Qualification Programs for erectors of precast concrete (Shutt, 2000) With the ever-increasing demand for quality, the certification of manufacturers, erectors and personnel provides the customer the assurance that quality systems are being followed, personnel are qualified and control is practiced through each step of the construction process Independent, unannounced audits help to assure process control PCI PLANT CERTIFICATION The certification of a manufacturing plant by PCI ensures that the plant has developed and documented an in-depth, in-house quality system that is based on timetested national industry standards Standards Production and quality standards are contained in the PCI publication, Manual for Quality Control for Plants and Production of Structural Precast Concrete Products (MNL-116) This manual has been recognized by the construction industry as the standard for the manufacture of precast and prestressed concrete since it was first printed in 1970 MNL-116 is the only such recognized national standard for the industry Production Experience Each company must have at least one year of production experience in order to qualify for certification Quality System Manual Every plant must document their specific practices in a custom Quality Systems Manual (QSM) The requirements for the QSM are contained in Division and Appendix A of MNL-116 Fifteen separate sections require that all operations in the plant be addressed thoroughly by management Each QSM must be approved by PCI prior to certification and must then be reviewed annually and updated if necessary Plants can obtain additional assistance for compiling a QSM in the PCI publication Preparation Guidelines for a Structural Plant Quality System Manual (2000) Audits/Auditors Nearly all new plants undergo a “Precertification Evaluation” after which a plant is audited twice each year These audits are not announced in advance Auditors are independent, specially trained engineers They are employed by a single consulting engineering firm under contract to PCI, which ensures consistency for every plant (Shutt, 1994) Closing Meeting/Reports Every audit ends with a closing meeting Auditors and key plant personnel meet to review preliminary results If improvements are needed, they can be started right away Later, a detailed written analysis documents observations and reasons for required improvements The report also includes a numerical grade sheet that indicates the level of compliance with the standards Grades The numerical grade sheet is organized with each section of the gradesheet corresponding to a division (chapter) of MNL-116 During an audit, each division is evaluated separately Grades in each division must meet or exceed an established miniSEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 PCI BRIDGE DESIGN MANUAL 11:11 AM Page APPENDIX F PCI CERTIFICATION PROGRAMS mum value Then, the grades for all divisions are combined into an overall grade A minimum overall grade must also be achieved for certification Audits are evaluated on a strict pass-fail criteria A failing grade requires a Special Immediate Audit Failure of that audit or the subsequent Regular Audit results in loss of Certification Product Groups A plant is evaluated and classified according to the type of products produced This allows for a more product-specific inspection and analysis of a plant’s specialized capabilities It provides specifiers with more information about the production experience of precast plants Plants, including bridge products producers, may be certified in up to four general groups of products The manuals listed in parenthesis contain the standards for certification in that Group Group A Group B or Group BA Group C or Group CA Group G Architectural Concrete Products (MNL-117) Bridge Products (MNL-116) or the combination of the A and B Product Groups (MNL-116) Commercial (Structural) Products (MNL-116) or the combination of the A and C Product Groups (MNL-116) Glass Fiber Reinforced Concrete Products (MNL-130) Product Categories The Product Groups are further divided into Categories that define a product’s reinforcement or the ways in which the products are manufactured or used Product Categories that include prestressing may incorporate pretensioning or post-tensioning or both Bridge products producers must be certified in one Category from Group B or Group BA Group B Categories B1 – Precast Bridge Products (no prestressed reinforcement) Examples include pile caps, retaining wall components, three-sided boxes or arches, median barriers, parapet walls, railings, fascia panels, abutment panels, sound barriers, pier columns, pier caps, precast diaphragms and conventionallyreinforced segmental units, and partial- and full-depth deck panels B2 – Prestressed Deck and Miscellaneous Bridge Products (non-superstructure) Examples include prestressed (pretensioned or plant post-tensioned) pier columns, pier beams, sound walls, fascia panels, piles, sheet piles, partialand full-depth deck panels B3 – Prestressed Straight-Strand Bridge Beams (superstructure) Examples include solid-slab beams, voided slabs, box beams, I-beams, bulbtees, double tees, multiple-stemmed units, box beam segments with pretensioned or plant post-tensioned prestressing B4 – Prestressed Deflected-Strand Bridge Beams (superstructure) Examples include box beams, I-beams, bulb-tees, double tees, multiplestemmed units and plant post-tensioned precast beams with draped tendons Group BA Categories Group B Category products with an architectural finish (see additional information that follows) B1A – Precast Bridge Products with Architectural Finish (no prestressed reinforcement) B2A – Prestressed Miscellaneous Bridge Products with Architectural Finish (nonsuperstructure) SEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 11:11 AM Page APPENDIX F PCI BRIDGE DESIGN MANUAL PCI CERTIFICATION PROGRAMS B3A – Prestressed Straight-Strand Bridge Beams with Architectural Finish (superstructure) B4A – Prestressed Deflected-Strand Bridge Beams with Architectural Finish (superstructure) Producers may also be certified in one or more of the following Groups and Categories Group A Categories AT – Miscellaneous Architectural Trim Units A1 – Architectural Precast Concrete Products Group C Categories C1 – Precast Concrete Products (no prestressed reinforcement) C2 – Prestressed Hollow-Core and Repetitively-Produced Products C3 – Prestressed Straight-Strand Structural Members C4 – Prestressed Deflected-Strand Structural Members Group CA Categories Group C Category products with an architectural finish (see additional information that follows) C1A – Precast Concrete Products with Architectural Finish (no prestressed reinforcement) C2A – Prestressed Hollow-Core and Repetitively-Produced Products with Architectural Finish C3A – Prestressed Straight-Strand Structural Members with Architectural Finish C4A – Prestressed Deflected-Strand Structural Members with Architectural Finish Within a Product Group, the Categories listed above are intended to be in ascending order of production complexity A producer qualified to produce products in a given Category is automatically qualified in the preceding Categories but not in succeeding Categories See the following Guide Qualification Specifications and accompanying notes for more details For more descriptive information about the types of products and projects that are represented by these Categories, contact PCI, visit the PCI website at www.pci.org, or refer to other more-detailed program literature from PCI Architectural Finishes – Product Groups BA and CA Beginning with the Fourth Edition of MNL-116 (1999), an additional product distinction was made available to the specifier The new classification defines products that have architectural finishes applied to more traditional structural products Before now, these products were not addressed in either MNL-116 or MNL-117 The special requirements for finish, texture, color, tolerances and quality control are included at the end of each division of manual MNL-116 Identification of BA and CA Producers The architectural finishes designation may be applied to any “B” or “C” category Qualified producers will be identified with the suffix “A” following their normal designation of “B1” through “B4” and “C1” through “C4.” For example, if a precaster is certified to produce precast sound barrier wall panels with conventional steel reinforcement and with an exposed aggregate surface finish, the appropriate designation will be “B1A.” A bridge-products producer that manufactures prestressed fascia panels SEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 11:11 AM Page APPENDIX F PCI BRIDGE DESIGN MANUAL PCI CERTIFICATION PROGRAMS with an architectural finish for a bridge would be required to hold “B2A” certification Refer to the Guide Qualification Specification near the end of this appendix for information about how to specify this and other Bridge Groups and Categories List of Certified Plants A current listing of all PCI Certified Plants is published quarterly in PCI’s ASCENT magazine A convenient searchable list is regularly updated on the PCI website at www.pci.org, or contact Director of Certification Programs at PCI Endorsements PCI holds a National Evaluation Report (NER QA-105) as an approved Quality Assurance Agency by the National Evaluation Service (NES) The NES includes: • Building Officials and Code Administrators Evaluation Service Inc (BOCA ES) • Southern Building Code Congress International, Public Safety Testing and Evaluation Services Inc (SBBCI PST&ESI) PCI holds a separate registration (AA-658) as an approved Quality Assurance Agency by the International Conference of Building Officials Evaluation Service Inc (ICBO ES) PCI Plant Certification is included in the MasterSpec of the American Institute of Architects and is required in the specifications of the following federal agencies: • U.S Army Corps of Engineers, Civil Works Division & Military Programs • U.S Naval Facilities Engineering Command (NAVFEC) • Federal Aviation Administration • General Services Administration • U.S Department of Agriculture, FSIS • U.S Department of Interior, Bureau of Reclamation Plant Certification is strongly endorsed in correspondence by the Federal Highway Administration (Kane, 1996) for precast concrete bridge products and is required or accepted by more than two-thirds of the individual state departments of transportation (Merwin, 1995) PCI PLANT QUALITY PERSONNEL CERTIFICATION Conducting an effective quality control program requires knowledgeable and motivated testing and inspection personnel Each must understand quality basics, the necessity for quality control, how products are manufactured, and precisely how to conduct tests and inspections PCI has been training quality control personnel since 1974 In 1985, the first technician training manual was published by PCI and the first qualified personnel attained certification There are three levels of Plant Quality Personnel Certification PCI Plant Quality Personnel Certification, Level I Level I requires six months or equivalent of approved industry experience It requires a basic level of understanding of the many quality control issues normally encountered in a precast plant, such as: • Quality and quality control programs, testing and measuring • Prestressing concepts and tensioning procedures for straight strands, including basic elongation calculations SEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 PCI BRIDGE DESIGN MANUAL 11:11 AM Page APPENDIX F PCI CERTIFICATION PROGRAMS • Basic concepts about concrete – water-cementitious materials ratio (w/cm), types of cements, accelerated curing concepts • Control of purchased materials • Precast production procedures • Welding practices including welding of reinforcing bars and studs • Interpretation of basic shop drawings Certification at Level I requires current certification in the American Concrete Institute (ACI) Concrete Field Testing Technician Program, Grade I The ACI certification requires a closed-book written test and precise field demonstration of seven ASTM methods to test properties of fresh concrete Certification at Level I is accomplished by passing a closed-book written examination Examinations may be administered locally by a PCI-approved proctor or at a PCI-conducted training school A manual for training and self-study (TM-101) is available from PCI Level I must be renewed by testing every five years unless a higher level of PCI certification has been attained PCI Plant Quality Personnel Certification, Level II Level II certification requires one year of approved industry experience or equivalent plus PCI Level I and current ACI Level I as prerequisites Other requirements for Level II include a greater level of knowledge of most of the topics previously described for PCI Level I, as well as: • Tensioning and elongation corrections that account for temperature effects, chuck seating, abutment movement and bed shortening Calculations for elongation and corrections are required • Effects of accelerated curing and importance of w/cm are further emphasized Corrections to mix proportions must be calculated to account for excess moisture in the aggregates • Material control tests are further explored including aggregate gradations and analysis Calculations are required for gradation analysis • Plant topics include more detail in reading shop drawings and in procedures for welding reinforcing bars and studs Certification through Level II is accomplished by passing a closed-book written examination Examinations may be administered locally by a PCI-approved proctor or at a PCI-conducted training school A manual for training and self-study for Level II (TM-101) is available from PCI Level II must be renewed every five years by testing unless Level III has been attained PCI Plant Quality Personnel Certification, Level III Level III provides significant instruction in concrete materials and technology Certification at this level requires two years of approved industry experience (or equivalent) and attendance at a four-day PCI school The candidate must pass a closedbook written examination at the school PCI Level II certification is a prerequisite Certification at Level III is valid for life There is a training manual (TM-103) available from PCI that covers all course topics, including: • Properties of: - Basic concrete materials - Admixtures - Fresh concrete - Hardened Concrete SEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 PCI BRIDGE DESIGN MANUAL 11:11 AM Page APPENDIX F PCI CERTIFICATION PROGRAMS • Mix designs using normal and lightweight aggregates • Architectural concrete • Troubleshooting and fine-tuning concrete mixes • Finished product evaluation • Stud welding and welding of reinforcing steel • Deflected prestressing strands and the calculation of deflection forces Agency Requirement Plant Quality Personnel Certification is required by nearly a third of the individual state departments of transportation They require certification for plant quality personnel and for their own materials inspectors and quality assurance personnel SUMMARY The precast, prestressed concrete industry, through PCI, has taken bold steps to establish industry quality standards The standards apply to personnel, to production and operations, to quality control, and to field operations The standards have been published and widely disseminated and are open for evaluation and written comments, all of which will be given consideration The PCI industry standards for quality production are demanding to achieve Once attained and practiced regularly, adherence to these standards contributes to improved and continuing customer satisfaction Following these standards has been shown to reduce the “cost of quality” for the owner as well as the producer Certification by PCI assures compliance to the published standards for quality production Certified personnel and producers choose to demonstrate their proficiency by voluntarily undergoing examinations and audits by accredited third-party assessors PCI Plant and Personnel Certification are reliable means for qualifying personnel and precast concrete producers Use the Guide Qualification Specification that follows to require PCI Certification Programs for your projects GUIDE QUALIFICATION SPECIFICATION The following guide specification can be used to qualify a precast concrete manufacturer to submit a bid on your project Generally, the easiest procedure would be to list the precast product or the various precast products included in your project Then, determine the appropriate Product Group and Category for each product, considering the use of the product, the method of reinforcement and special required surface finishes, if any Show each of the products and the required Group and Category in the project specifications Refer to the following “Notes to Specifiers” for additional discussion.Product categories that include prestressing may incorporate pretensioning or post-tensioning or both Further, it is recommended that the manufacturer employ trained and certified personnel according to the Personnel Qualifications guide specification that follows Manufacturer Qualifications – Structural Precast Concrete The precast concrete manufacturing plant shall be certified under the Precast/Prestressed Concrete Institute Plant Certification Program The Manufacturer shall be certified at the time of bidding Certification shall be in the following Product Group(s) and Category(ies): [Select and insert one or more of the following applicable groups and categories] SEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 PCI BRIDGE DESIGN MANUAL 11:11 AM Page APPENDIX F PCI CERTIFICATION PROGRAMS Group B – Bridge-Related Products B1 – Precast Bridge Products (no prestressed reinforcement) B2 – Prestressed Miscellaneous Bridge Products (non-superstructure) B3 – Prestressed Straight-Strand Bridge Beams (superstructure) B4 – Prestressed Deflected-Strand Bridge Beams (superstructure) Group BA – Bridge-Related Products that Require Architectural Finishes B1A – Precast Bridge Products with Architectural Finish (no prestressed reinforcement) B2A – Prestressed Miscellaneous Bridge Products with Architectural Finish (nonsuperstructure) B3A – Prestressed Straight-Strand Bridge Beams with Architectural Finish (superstructure) B4A – Prestressed Deflected-Strand Bridge Beams with Architectural Finish (superstructure) Notes to Specifiers: Additional guide specifications, not shown here, are available from PCI for Product Groups “A,” “C” and “G.” Categories in Product Group B are listed in ascending order of production complexity For example, a plant certified to produce products in Category B4 is automatically certified to produce products in the preceding Categories B1, B2 and B3 However, a plant certified to produce products in Category B2, while certified for Category B1, is not certified for Categories B3 or B4 Categories in Group BA are also listed in ascending order See Notes & 4 Group BA supercedes Group B in the same Category For example, a plant certified to produce products in Category B4A is automatically certified to produce products in the preceding Categories B1A, B2A, B3A, and in categories B1, B2, B3 and B4 However, a plant certified to produce products in Category B2A, while also certified for Categories B1A, B1 and B2, is not certified for Categories B3A, B4A, B3 or B4 A Product Group and Category should be determined and shown in the specifications for each type of precast concrete product used in a project Separating products will enable precasters to submit bids on specific products For example, on a project that included both prestressed piling and beams, a precaster with expertise in producing prestressed piling (with Certification B2) could submit a price on piles only On the same project, a producer with Certification B4 could submit a price for the beams and decide to either include or exclude the piling Specify the most appropriate Product Group and Category for the project Do not select a higher Category than necessary Similarly, not add “A” to a listing when not necessary to meet project requirements Selecting an inappropriate Group or Category could result in unnecessary cost or could restrict the number of available bidders SEPT 01 5970 Bridge Manual APPENDIX F 9/21/01 PCI BRIDGE DESIGN MANUAL 11:11 AM Page APPENDIX F PCI CERTIFICATION PROGRAMS Personnel Qualifications The Manufacturer shall employ a minimum of one person, regularly present in the plant, who is certified by the Precast/Prestressed Concrete Institute for Plant Quality Personnel, Level II All other personnel regularly engaged in the measuring, testing or evaluation of products or materials shall be similarly certified, or actively pursuing certification for Plant Quality Personnel, Level I REFERENCES Duggleby, J., “Setting a Higher Standard,” ASCENT Fall, 1992 Precast/Prestressed Concrete Institute, Chicago, IL, pp 28-31 Shutt, C., “Erector Qualification Brings Precast Quality Assurance Full Circle,” ASCENT, Fall 2000, Precast/Prestressed Concrete Institute, Chicago, IL, pp 122-123 Preparation Guidelines for a Structural Plant Quality System Manual, QSM-1, Precast/Prestressed Concrete Institute, Chicago, IL, 2000, 50 pp Shutt, C., “Ross Bryan Associates Makes the Grade,” ASCENT, Winter 1994, Precast/Prestressed Concrete Institute, Chicago, IL, pp 12-16 Manual for Quality Control for Plants and Production of Structural Precast Concrete Products, Fourth Edition, MNL-116-99, Precast/Prestressed Concrete Institute, Chicago, IL, 1999, 283 pp Manual for Quality Control for Plants and Production of Architectural Precast Concrete Products, Third Edition, MNL-117-96, Precast/Prestressed Concrete Institute, Chicago, IL, 1996, 236 pp Manual for Quality Control for Plants and Production of Glass Fiber Reinforced Concrete Products, MNL-130-91, Precast/Prestressed Concrete Institute, Chicago, IL, 1991, 184 pp Kane, A., Letter (Unpublished), Federal Highway Administration, Washington, DC, 1996 Merwin, D P., “Two States Bridge the Quality Gap,” ASCENT, Spring 1995, Precast/Prestressed Concrete Institute, Chicago, IL, pp 18-21 Quality Control Technician/Inspector Level I & II Training Manual, TM-101, Precast/Prestressed Concrete Institute, Chicago, IL, 1987, 246 pp Quality Control Personnel Certification Level III Training Manual, TM-103, Precast/Prestressed Concrete Institute, Chicago, IL, 1996, 244 pp SEPT 01 ... KIỂM TOÁN BỆ TRỤ HẠNG MỤC :HẠ TẦNG I DỮ LIỆU BAN ĐẦU : LOẠI CẤU KIỆN KIỂM TỐN : BỆ TRỤ PHƯƠNG DỌC CẦU • Kích thước cấu kiện theo phương Y b = 13200.000 mm • Kích thước cấu kiện theo phương X h =