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ACI 533.1R-02 became effective June 26, 2002. Copyright  2002, American Concrete Institute. All rights reserved including rights of reproduction and use in any form or by any means, including the making of copies by any photo process, or by electronic or mechanical device, printed, written, or oral, or recording for sound or visual reproduction or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors. ACI Committee Reports, Guides, Standard Practices, and Commentaries are intended for guidance in plan- ning, designing, executing, and inspecting construction. This document is intended for the use of individuals who are competent to evaluate the significance and limita- tions of its content and recommendations and who will accept responsibility for the application of the material it contains. The American Concrete Institute disclaims any and all responsibility for the stated principles. The Institute shall not be liable for any loss or damage arising therefrom. Reference to this document shall not be made in contract documents. If items found in this document are desired by the Architect/Engineer to be a part of the contract documents, they shall be restated in mandatory language for incorporation by the Architect/Engineer. 533.1R-1 Design Responsibility for Architectural Precast-Concrete Projects ACI 533.1R-02 Architectural precast concrete is a unique subcategory of concrete construction that involves the same basic entities as other construction. This document outlines the responsibilities for various parties of the design/construction team for architectural precast-concrete projects. Keywords: Architect; architectural concrete; construction; design; design responsibility; general contractor; precast concrete. CONTENTS Chapter 1—Introduction, p. 533.1R-1 1.1—Background Chapter 2—General responsibilities, p. 533.1R-2 2.1—Architect 2.2—Engineer of record 2.3—General contractor 2.4—Precaster (manufacturer) 2.5—Erector 2.6—Inspection Chapter 3—Forms of contracts, p. 533.1R-4 3.1—Negotiated versus competitive bid 3.2—Single-source responsibility 3.3—Mockups Chapter 4—Conclusion, p. 533.1R-5 Chapter 5—References, p. 533.1R-5 5.1—Referenced standards and reports Appendix—Prebid process, p. 533.1R-6 CHAPTER 1—INTRODUCTION Design and construction of structures is a complex process. Defining the scope of work and the responsibilities of the involved parties by means of the contract documents is necessary to achieve a high-quality structure. This is a guide document for all parties involved in a precast-concrete project and defines the responsibilities of each party. This document does not specifically address the inspection functions but provides direction on who should be conducting inspections. These responsibilities are subject to relationships between the parties defined in the contract documents. 1.1—Background Practices regarding the assignment and acceptance of responsibility in design and construction vary throughout North America. In many cases, there has been confusion regarding the responsibility of the various parties. This situation has sometimes led to protracted legal proceedings. The first consensus document to attempt to define essential Reported by ACI Committee 533 Robert B. Austin Edward M. Frisbee Navin N. Pandya George F. Baty Harry A. Gleich James B. Quinn Harry A. Chambers Thomas J. Grisinger Ralph C. Robinson † Sidney Freedman * Theodore W. Hunt † Joseph R. Tucker Allan R. Kenney ____________ * Primary author. † Deceased. Benjamin Lavon Chair Donald F. Meinheit Secretary 533.1R-2 ACI COMMITTEE REPORT roles was Quality in the Constructed Project, published by the American Society of Civil Engineers (ASCE) in 1990 (ASCE 1990). In 1987, ACI organized a standing board committee on Responsibility in Concrete Construction. The document, Guide- lines for Authorities and Responsibilities in Concrete Design and Construction, was published by the committee (ACI Committee on Responsibility in Concrete Construction 1995). One of the basic principles of the construction industry is that responsibility and authority should go hand in hand. Another principle is that every entity should be responsible for its own work. These principles are frequently violated. For example, an architect/engineer (A/E) can require that certain tasks not be undertaken by the contractor without the A/E’s approval, but the A/E may not wish to accept respon- sibility for problems that develop resulting from requiring those tasks. This is a case of requiring compliance without accepting responsibility. There have also been cases where owners have sued architects and engineers for approving poor-quality construction but gave them no contract to monitor the work as it progressed. Safety enforcement agencies and plaintiffs’ lawyers have often charged engineers or architects with the responsibility for construction accidents. These last two situations typically are cases of responsibility without authority, although there could be instances where a design professional’s work can affect jobsite safety. If the designers are involved with construction-management functions, they could be making decisions affecting worker safety as well as quality of construction. Construction has reached a level of complexity today where it is essential to have design input from the subcontractors. This input, whether submitted as value engineering proposals, in response to performance requirements, or simply offered as design alternatives, has a legitimate place in construction. Panels are designed for stripping, handling, and installation loads, usually by the panel manufacturer. Service loads are set by the governing building code and are multiplied by the appropriate load factor. Minimum load factors are set by the governing building code. Panel design should consider dead, live, and environ- mental loads including wind, earthquake (if applicable), temperature, and moisture effects. Service loads set by the governing building code should be considered only as minimum requirements. Frequently, a precaster wants to change some items in the design to make a fabrication or erection operation easier or more economical. In approving the changes, the A/E still has responsibility for proper interfacing with other materials in contact with precast concrete. This notion of responsibility is presented in the ASCE document (ASCE 1990) and in the Precast/Prestressed Concrete Institute’s guidelines (PCI Ad-Hoc Committee for Responsibility for Design of Precast-Concrete Structures 1998). The engineer of record (EOR) always has to take overall responsibility for the structural design of the complete structure. Often, certain aspects of the design are delegated to specialty engineers working for the material suppliers or subcontractors. When any of this structural design work for that portion of the structure involves engineering (as opposed to simply detailing), then the design work should be under the control of a professional engineer licensed in the same state as the project who takes responsibility for the work done. One state, Florida, has formal legal procedures for this process. Local regulatory authorities should be consulted for their specific requirements. Contract documents often require that structural design be the responsibility of a professional engineer, regardless of government mandate. CHAPTER 2—GENERAL RESPONSIBILITIES 2.1—Architect The architect develops the design concept, overall structure geometry, selects the cladding material for appearance, provides details for weatherproofing, selects tolerances for proper interfacing with other materials, and specifies perfor- mance and quality characteristics and inspection and testing requirements in the project specifications. The architect and EOR should have responsibility for all aspects of the precast-concrete design. The architect can specify in the contract documents that design services for portions of the work are to be provided by the precaster. Such design services should be performed for the precaster by a licensed precast engineer who can be an employee of the precaster or an independent structural engineer. The architect and EOR should review these designs, including structural calculations. This review does not relieve the precaster and the specialty engineer of their design responsibility. The contract and the design documents should state clearly the scope of both the precast design and review responsibilities, and the responsi- bilities of others providing design services. The contract drawings prepared by the architect/engineer should provide the overall geometry of the structure and typical connection concepts to permit design, estimating, and bidding. Frequently, the architect’s drawings will only show joints, reveals, or panel articulation. This lets the precaster determine panel sizes. In the prebid process, the precaster and erector should discuss their approach to panelize and subsequently connect the units to the building frame within the architectural and structural concepts of the project. In addition, the contract documents (design drawings and specifications) also should provide the general performance criteria, including concrete strength requirements for loading, deflection requirements, temperature considerations, and any tolerance or clearance requirements for proper interfacing with other parts of the structure. The contract documents should clearly define: • Precast-concrete components that are the design responsibility of the precaster (who takes responsibility for elements at interfaces with other parts of the structure, such as the secondary steel bracing to prevent rotation of beams or panels); • Details or concepts of supports, connections, and clearances that are part of the structure designed by the architect and that will interface with the precast- concrete components; and • Permissible load transfer points and indicate connection types to avoid having the precaster make assumptions on connection types and piece counts during bidding. The architect and EOR should review designs, calculations, and shop drawings submitted for conformance with design criteria, loading requirements, and design concepts as specified in the design documents. This review, however, does not relieve the precaster and the precast engineer of their design responsibilities. Key design issues for the architect—Buildings using architectural precast panels are becoming increasingly DESIGN RESPONSIBILITY FOR ARCHITECTURAL PRECAST-CONCRETE PROJECTS 533.1R-3 complex. The architect should understand the issues that affect a precaster’s bid and make sure the contract documents address these items clearly. For preparation of shop drawings, all items interfacing with other materials should be defined. Contract documents that lack detail generally require numerous requests for information. While such documents are easier and less expensive to produce, they may ultimately result in disputes, delays, and additional costs. The contract drawings developed by the architect should provide a clear interpretation of the configurations and dimensions of individual units and their relationship to the structure as a whole. To do this, the contract documents should supply the following data: • Elevations, wall sections, and dimensions necessary to define the sizes and shapes of each different type of wall panel; • Locations and sizes of all joints, both real (functional) and false (aesthetic). Joints between units should be completely detailed; • Required materials and finishes for all surfaces, with a clear indication of which surfaces are to be exposed to view when in place; • Corner details; • Details for jointing and interfacing with other materials (coordinated with the general contractor); • Details for special or unusual conditions, including fire requirements; • Governing building code and design loads; • Deflection limitations; and • Specified dimensional tolerances for the precast concrete and the supporting structure, location tolerances for the contractor’s hardware, clearance requirements, and erection tolerances for the precast concrete. Any exceptions to industry tolerances specified in the contract documents are not recommended. Lack of detail will extend shop drawing time and potentially lead to disputes over work scope, schedule delays, or both. Also, lack of detail can lead to unanticipated changes that will impact cost. Poor detailing of panel cross sections within the contract documents will often lead to disputes. Ideally, the assembly (or erection) drawing process should be as simple as submitting elevations showing panel sizes, surface features, and panel relationships; detail sheets showing panel cross sections and special edge conditions, and feature details; and connections showing mechanisms and locations of force transfer to the supporting structure. The review of shop drawings by the architect should be performed within the time specified in the contract documents. These drawings should be reviewed and any minor revisions made so that production can start. Verification of minor dimensional and detailing revisions is anticipated. When major shop drawing revisions are required, however, it can indicate a lack of planning or detailing within the contract documents. It is the architect’s responsibility to establish the standards of acceptability for surface finish, color range, and remedial procedures for defects and damage. This can be best accom- plished by the precaster producing at least three sample panels a minimum of 4 x 4 ft before the initial production to establish the range of acceptability with respect to color and texture variations, surface blemishes, and overall appearance. When the units have returns, the same size return should appear in the sample panels. 2.2—Engineer of record The EOR has responsibility for describing loading on precast element inserts and loading criteria (combinations, wind, seismic) for the structural design of the complete structure and the effects of the precast erection sequences on individual structural members, for example, steel spandrel beams when numerous concentrated panel loads are placed on them. The EOR should anticipate these loadings and provide means to support them. Responsibility for the precast-concrete design can be delegated to someone else, such as the precaster or precast engineer. The EOR should consider the consequences of the weight and eccentricity of the panels when designing the supporting structure. The EOR should also determine where, when, and what type of loading is to be assigned to the panels and the structure. The EOR has the responsibility of reviewing the delegated design work for compatibility with the overall structural design. This does not, however, relieve the preparer of the design work of the responsibility for doing it correctly. Panels typically span column to column and are supported on or near the column. The EOR should determine and show on the contract documents the locations for supporting the gravity and lateral loads, including midpoint lateral (tie-back) connections, if necessary. The panel loads are routinely provided by the precaster to the EOR. The EOR determines during assembly (erection) drawing review whether or not the structure is adequate, within defined deflection limitations, to resist the loads and forces. The EOR should also provide sufficient information on seismic detailing. It is important that preliminary meeting(s) with the architect, EOR, and precasters be held before structural members are ordered, fabricated, or both, so that panel sizes, shapes, and basic connections, as well as their locations can be established (refer to the Appendix). The EOR will know whether or not a spandrel panel is designed to transfer load to the columns, but the exact location of the load transfer can vary from precaster to precaster. For example, spandrel panel loads can be transferred from near the panel bottom or from near the top. The gravity supports of precast-concrete panels are almost always eccentric to the centerline of the supporting steel or concrete member. A concrete member is generally stiff and strong enough in torsion so that this is not a problem. Because the precaster does not design the columns or beams, the EOR should design to prevent excessive deflection and rotation of the supporting structure during and after erection of the precast concrete, as well as determine the need for diagonal bracing or web stiffening (CASE National Guidelines Committee 1994; CASE Task Group on Specialty Engineering 1996). The contract documents should address the issue of reimburse- ments to the EOR for engineering the bracing or reinforcement of the structure if the precaster’s panelization changes the EOR’s designed connection locations. In some areas, the precaster is responsible for designing the bracing and may also supply the secondary steel. These responsibilities should be clearly addressed in the contract documents and discussed in a prebid meeting. 2.3—General contractor The general contractor (GC) typically has responsibility and authority for implementing the design intent of the 533.1R-4 ACI COMMITTEE REPORT contract documents, which includes furnishing materials, equipment, labor, maintaining specified quality require- ments, and coordinating all trades. The GC is responsible for construction means, methods, techniques, sequences, and construction procedures. Also, the GC should initiate, maintain, and supervise all safety procedures and programs on the construction site. Site access to the structure for erection of the precast elements can become a problem. The responsibility to provide and maintain access roads should be clearly stated in the contract documents. The GC has no design responsibility. The GC, however, does have considerable impact on the design process through its coordination role. The GC receives the different shop drawing submittals from the various trades and puts them together to form the completed design. The GC is normally responsible for project schedule, grid dimensions (which include control points, benchmarks, and lines on the building), quantities, and dimensional interfacing of the precast concrete with other trades, and maintenance of specified tolerances of the structure to ensure proper fit. During shop drawing review, the GC should notify the precaster when as-built conditions (dimensions) vary beyond tolerances on the contract drawings. In particular, dimensional tolerances between interfacing materials, such as precast concrete and glazing, should be considered. The GC should be a party to direct communication between the precaster, EOR, and the architect. Communication channels should be established among the parties. The GC needs to be informed in writing, particularly if decisions affect the GC’s activities. Typically, the GC is responsible for placing embedments in cast-in-place concrete and coordinating steel attachments with the steel fabricator. In most instances, the most economical approach is to have gravity haunch connection hardware attached to steel columns by the steel fabricator. This necessi- tates awarding the precast-concrete contract in a timely manner. 2.4—Precaster (manufacturer) To achieve practical and economical construction, the precaster first designs panelization and then connections. Ideally, a precaster performs value engineering as early as during preliminary design (in a partnering relationship) to improve economics, structural soundness, and performance. The precaster should request clarification of ambiguities, in writing from the architect, through contractual channels on special conditions not clearly defined in the contract documents. When the construction schedule demands a rapid turnaround time for review of drawing submittals, the precaster should notify all concerned of their obligations to review and return submitted drawings within the requested time period. At that time, the architect’s and EOR’s cooperation is needed to expe- ditiously review submitted documents. The precaster or precaster’s specialty engineer prepares detailed assembly, or erection drawings and design calcu- lations that are usually signed and sealed. These drawings, calculations, or both, should show all design criteria, identify each material, show how precast panels interface with each other and the structure, and indicate the magnitude and location of all design loads imparted to the structure by the connections. The precaster or specialty engineer designs the precast panels for the specified loads and is responsible for selecting, designing, and locating hardware, and panel reinforcement or items associated with the precasters methods of handling, storing, shipping, and erecting precast-concrete units. If necessary, this also includes an erection and bracing sequence developed in conjunction with the erector, EOR, and GC to maintain stability of the structure during erection. Any additional design responsibility vested with the precast-concrete manufacturer should be defined clearly in the contract documents prepared by the architect. Most precast-concrete work is covered in Option II, Table 1. Option I in Table 1 has considerable liability for the architect and EOR. 2.5—Erector The responsibility for erection of architectural precast concrete is usually determined by the GC. The contract documents rarely require that the erection be part of the precast-concrete manufacturer’s work, be performed by the precaster’s workers, or be subcontracted to specialized erection firms. Fabrication and erection included into one contract is preferred by some precasters because this improves coordination and reduces vulnerability to backcharges. The GC, however, may choose to issue separate contracts for fabrication and erection. Erectors and precasters coordinate development of efficient connections for each project based on their equipment and expertise. 2.6—Inspection Quality control for product manufacturing will be provided by the precaster according to provisions contained in a comprehensive quality system manual developed by the precaster. The quality system manual will be available to the owner and EOR for review. Quality assurance will be provided through the precaster’s participation in a recognized industry quality certification program. One such program is the PCI Plant Certification Program. Additional inspections may be required, by specifica- tion, through the owner’s quality-assurance agency. Installation quality assurance will be provided by adherence to industry standards such as the PCI Erectors’ Manual. Additional quality assurance can be provided by requiring installation by an industry-qualified erector. CHAPTER 3—FORMS OF CONTRACTS 3.1—Negotiated versus competitive bid The price of architectural precast concrete is a relatively small percentage of the total building cost (usually less than 10%). Therefore, the possible difference in the price between the lowest precast bidder and the precaster who is ultimately awarded the contract will have a minor impact on the overall cost. In a negotiated project, the precaster can become part of the building team at the very early design stage and be more effective in providing valuable expertise on panel design, performance, and economics (refer to Appendix). 3.2—Single-source responsibility The architect or owner sometimes prefers single-source responsibility for wall cladding (which includes windows, precast, and all related sealants) responsibility for the following reasons: to enhance technical and aesthetic coordination between building systems; to establish a single-source warranty; to centralize control for erection and problem- solving issues; and generally, to provide for a single source of knowledge and total understanding of the entire system. In DESIGN RESPONSIBILITY FOR ARCHITECTURAL PRECAST-CONCRETE PROJECTS 533.1R-5 single-source responsibility, detailing issues are delegated to the contractor and material suppliers of the wall. Single-source responsibility usually puts the precaster in a position of a broker/contractor without having the management and engineering skills to work out interfacing details for the window system, insulation, interior finishes, and sealants. A more logical entity for single-source responsibility is the GC. In some cases, the GC may prefer that single-source responsibilities be separated for greater profit potential. Generally, the precast-concrete industry tends to avoid single-source responsibility, not only because of technical concerns regarding materials whose quality they do not control directly but also due to economics. It can be uneconomical to package everything under the precaster’s construction umbrella because this additional responsibility requires additional compensation. The notion of a single-source responsibility for exterior enclosure can break down if that single source is not clearly defined. 3.3—Mockups Panel-to-panel joint design is necessary to prevent air and water infiltration, and to properly seal windows and other openings. The architect is responsible for these designs. Because precast concrete is inherently watertight and imperme- able, the panel joints and interfacing performance become the primary concerns. If testing is desired, it should be specified in the contract documents. Shipping a full-scale mockup to a testing lab for a wind-driven rain test, although costly and time consuming, is one way to satisfy these concerns. Also, aesthetics can be refined during this process. The cost of these tests needs to be identified in the bid documents and included in the precast budget. A mockup will help determine how the total facade is assembled. Also, it will help in establishing the actual field-construction techniques. If a leak develops, which usually occurs at the window to precast-concrete inter- face, the details need to be examined and modified. The contract documents should require that the same sealant contractor seal both the precast-to-precast panel joints and the window interface to avoid sealant incompatibility. CHAPTER 4—CONCLUSION A successful precast-concrete project requires teamwork. This means close cooperation between and coordination of all participants, including the owner, architect, engineer, precast-concrete manufacturer, erector, general contractor or construction manager, and all trades. The precast work scope and the responsibilities of each party (usually defined by the contract documents) should be established at an early stage in the development of a project to achieve the desired results and schedule (refer to Table 1). Each party has the responsi- bility for communicating with all other parties through the GC/CM to achieve optimum efficiency during construction, and quality in the completed structure. When authority and responsibility roles are correctly and properly defined by the contract documents and communicated, responsibility issues are easily resolved. CHAPTER 5—REFERENCES 5.1—Referenced standards and reports ACI Committee on Responsibility in Concrete Construction, 1995, “Guidelines for Authorities and Responsibilities in Concrete Design and Construction,” Concrete International, V. 17, No. 9, Sept., pp. 66-69. American Society of Civil Engineers (ASCE), 1990, “Quality in the Constructed Project,” Manuals and Reports on Engineering Practice No. 73, American Society of Civil Engineers, New York, N.Y. CASE National Guidelines Committee, 1994 “National Practice Guidelines for the Structural Engineer of Record,” Table 1—Design responsibilities Contract information supplied by designer Responsibility of manufacturer of precast concrete Option I Provide complete drawings and specifications detailing all aesthetic, functional and structural requirements plus dimensions. The manufacturer should make shop drawings (erection and production drawings) as required, with details as shown by the designer. Modifica- tions may be suggested that, in manufacturer’s estimation, would improve the economics, structural soundness, or performance of the precast- concrete installation. The manufacturer should obtain specific approval for such modifications. Full responsibility for the precast-concrete design, including such modifications, remains with the designer. Alternative proposals from a manufacturer should match the required quality and remain within the parameters established for the project. It is particularly advisable to give favorable consideration to such proposals if the modifications are suggested so as to conform to the manufacturer’s normal and proven procedures. Option II Detail all aesthetic and functional requirements but specify only the required structural performance of the precast-concrete units. Specified performance should include all limiting combinations of loads together with their points of application. This information should be supplied in such a way that all details of the unit can be designed without reference to the behavior of other parts of the structure. The division of responsibility for the design should be clearly stated in the contract. The manufacturer has two alternatives: (a) Submit erection and shape drawings with all necessary details and design information for the approval and ultimate responsibility of the designer. (b) Submit erection and shape drawings for general approval and assume responsibility for part of the structural design; that is, the individual units, but not their effect on the building. Firms accepting this practice may either stamp (seal) drawings themselves, or commission engineering firms to perform the design and stamp the drawings. The choice between the alternatives (a) and (b) should be decided between the designer and the manufacturer prior to bidding, with either approach clearly stated in the specifications for proper allocation of design responsibility. Experience has shown that divided design responsibility can create con- tractual problems. It is essential that the allocation of design responsibility is understood and clearly expressed in the contract documents. 533.1R-6 ACI COMMITTEE REPORT 2nd Edition, Coalition of American Structural Engineers, Washington, D.C., 15 pp. CASE Task Group on Specialty Engineering, 1996, “National Practice Guidelines for Specialty Structural Engineers,” Coalition of American Structural Engineers, Washington, D.C., 12 pp. PCI Ad-Hoc Committee for Responsibility for Design of Precast-Concrete Structures, 1998, “Recommendations on Responsibility for Design and Construction of Precast- Concrete Solutions,” PCI Journal, July-Aug., Chicago, Ill. APPENDIX Prebid process Where the selection of a precaster cannot be negotiated or controlled by owner or architect but is governed by an open- bid situation, the following prebid process is desirable. Step 1: Verification of architect’s concepts and systems— A preview of the proposed precast-concrete assumptions during the design development stage (50% complete) of the architec- tural contract documents should be arranged with at least one local precaster. This review confirms or modifies the concept so that a realistic approach is presented on the architect’s bid drawings. Those attending the meeting should: • Discuss panelization and piece and joint sizes, determine what can be made, and what can be shipped and erected efficiently; • Discuss architect’s concept for structural support of precast concrete so that the architect can communicate to the EOR what support requirements are needed; • Review desired finish(es) and continue or finalize the sample process; and • Review the architect’s intent for any interfaces with adjacent systems, such as roofing, windows, or building entrances. Step 2: The prebid conference—This should be a mandatory meeting for all precasters wanting to bid the project and is usually held at least 3 weeks before the bid date. The architect presents the project’s precast-concrete concepts with the intent of communicating straightforward information so bids will be prepared on a comparable basis. Questions can be asked or clarifications made at this time. Items to be discussed include: • How and where the project’s precast concrete will be structurally attached to the building frame; • Specifications and any special provisions; • Design responsibilities and lines of communication; • The architect’s approved finish samples with information on the type and size of aggregates and cement used, where applicable; • The finish acceptance criteria and inspection (who, what, when, and where); • Prebid submittal requirements such as proposal drawings and finish samples; • Mockups, if applicable; • Potential problems, discrepancies, or both found in the contract documents; and • Special erection needs and logistics. Step 3: Information submitted with bid or after-bid award— This submittal allows a review of each precaster’s intent and confirms the precaster’s ability to conform to concepts and finish requirements. (Realistically, only the three low bidders are required to provide this submission.) This material should include: • Proposal drawings expressing the panelization and structural concepts; • Small-size finish samples; • The history of the precaster’s organization as well as confirmation of the plant’s quality assurance (plant certification) program; • A list of comparable projects, references, and financial capability; • Key schedule items such as mockup panels, shop drawings and design submittals, mold production, scheduled start of manufacture, and production schedules; and • Qualifications to the bid that can be listed and reviewed. If bidders are limited to a small group (two to four) by prequalification or other means, then all precasters are contacted during the development process; then limited prebid meetings, bid submittals, or both are needed. If the project will allow for a negotiated precast contract and the precaster is brought onto the project team in the initial stages of development, then prebid and bid submittal information can be eliminated. Step 4: The preconstruction conference—A preconstruction conference should be held at the job site as soon as possible after award of the precast concrete and erection contracts. The GC/CM should conduct job site meetings frequently to coordinate the precast-concrete erection with the work of other trades and to facilitate the erection process. These meetings should include those subcontractors whose work affects or is affected by the precast-concrete erection. The coordinating meetings should consider all details of loading, delivery sequences and schedules, types of transportation, routes of ingress and egress for delivery trucks and erection cranes, handling techniques and devices, connections, erection methods and sequences, effects of temporary bracing on other trades, and on-site storage and protection. Questions regarding access, street use, sidewalk permits, oversized loads, lighting, or working hours should be addressed at this time. . responsibilities for various parties of the design/ construction team for architectural precast-concrete projects. Keywords: Architect; architectural concrete; construction; design; design responsibility; . their design responsibilities. Key design issues for the architect—Buildings using architectural precast panels are becoming increasingly DESIGN RESPONSIBILITY FOR ARCHITECTURAL PRECAST-CONCRETE PROJECTS. restated in mandatory language for incorporation by the Architect/Engineer. 533.1R-1 Design Responsibility for Architectural Precast-Concrete Projects ACI 533.1R-02 Architectural precast concrete

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