SANS 10120-3 GE-1984 Code of practice for use with standardized specifications for civil engineering construction and contract documents Part 3 Guidance for design Section GE Preca.pdf

1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA

2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any

3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. SAIE 0120 : Part 3 Section GE-1984 Precast concrete (structural) Clause 1 . 1.1 1.1.1 1.2 1.2.1 1.3 1.3.1 1.3.2 1.3.3 1.3.4 2 . 2.1 2.2 2.3 2.4 2.5 3 . 4

4、 . 4.1 5 . 5.1 5.2 PART 3 : GUIDANCE FOII DESIGN SECTION GE CONTENTS PRETENDER CONSIDERATIONS . Znvestigations Production facilities . Administration Tolerances . Documentation Project specification clauses Drawings . Points of support Specifying tolerances DESIGN REQUIREMENTS General Quality Proced

5、ure Precautions . Connection Details APPLICABILITY OF OTHER CODES TEST PROCEDURES General QUALITY CONTROL AND OTHER CONSIDERATIONS . Quality Control . Failures March 1984 Approved by the COUNCIL OF THE SOUTH AFRICAN BUREAU OF STANDARDS I lSBN 0-626-06890-8 SAUS 0120 : Part 3 :;ection GE-19114 Precas

6、t concrete (structural) SABS 1200 CE : PRECAST CONCRETE (STRUCTURAL) NOTE: The clause number(s) given at the beginning or after the heading of a clause is/are, unless otherwise stated, the number(s) of the relevant clause(s) of SARS 1200 GE. PRE-TENDER CONSIDERATIONS INVESTIGATIONS Production Facili

7、ties. Ascertain irom appropriate (and competent) manufacturers, the production facilities that will be available for the manufacture of the proposed structural precast concrete units. Having thus established the likely tenderers, discuss with them the methods of manufacture that are likely to be off

8、ered, the location of manufacturing centres, and the methods oC storage, handling, and erection. Discuss also details of typical fixings and determine the consequential interim stress implications. Tolerances. Ensure that working drawings to be used by the contractor or manufacturer, or both, as app

9、licable, give the dimensions and tolerances required by the engineer. DOCUMENTATION Project Specification Clauses (Subclauses 5.5 and 5.6). Do not include clauses that impose unnecessary or unenforceable restrictions on the contractors manufacturing process in such matters as heat curing and demould

10、ing. (See also Subclauses 3.1.5 and 3.1.6 of Section GE of Part 5 of the code.) Drawings Lifting details. Ensure that lifting details are practical and will give a safe lifting arrangement that is such that no damage will be caused by the lifting equipment. Fixing details. Ensure, by discussions wit

11、h potential manufacturers, that fixing details are practical and that the method of fixing will be safe during manufacture, curing, and transportation and also after erection. (See 1.1.1 above.) Reinforcement details (Subclause 5.5.2). Ensure that the dimensions .of reinforcement are so clearly -p-

12、given and scheduled that the contractor is able to comply with the requirement of SABS 1200 GE that no stirrups, links, or tying wire encroach into the specified cover. Take account of the requirements of Subclause 1.3.4 of Section G. Points of Support. In all cases, specify the points of support- d

13、uring storage and ensure that these are so chosen as to prevent unacceptable permanent distortion of the units. Supporting arrangements which allow small settlements to occur without stresses being induced in the units are preferred. Specifying Tolerances Cost. While dimensional variations are inevi

14、table, precast concrete units can be manufactured to - comparatively small permissible deviations. Manufacturing to small permissible deviations does, however, materially increase the cost of the units. Essential dimensions. Specify permissible deviations for only those dimensions that are important

15、 to the - correct assembly, performance, and appearance of the structure, and ensure that these PDs are as large as is practicable. Leave the permissible deviations for other dimensions to the discretion of the manufacturer, but ensure that these are reasonable for the conditions of production and u

16、se. The manufacturer must, when requested, make known his own permissible deviations. (See also 2.5 below.) Consistency with adjoining components. Take care that the permissible deviations for the units are consistent with any variation in the position of the adjoining components in the building. (S

17、ee also 2.5 below. Impact of tolerance requirements on moulds. The permissible deviations given in Clause 6 of SABS 1200 G) are of general applicability and, where closer values are necessary, can be reduced by as much as 50 X. However, ensure that any such reductions are restricted to the particula

18、r dimensions whose accuracy is important, as reduced PDs will necessitate a much hiqher standard of construction of the mould and closer supervision and inspection at all stages of manufacture, with consequent increased costs. In exceptional cases, it may be possible to reduce certain permissible de

19、viations even further by means of specially designed moulds, but such reductions must be made with considerable discretion. Manufacturers advice. It is strongly recommended that, when very small permissible deviations are likely to be required, the manufacturers advice be obtained at the early stage

20、s of design, as PDS that can be achieved in practice depend on a number of factors, including a) the shape of the unit, particularly as this affects the stiffness of the mould; b) the mould materials and the method of assembly; c) the number of castings made in each mould; and d) the position and sh

21、ape of any projections through the moulded faces. Irregular units. Define clearly in the project specification and by means of dimensions shown on drawings, the PDs for irregular, curved, or specially shaped units. If Concrete (structural). SABS 0170 : Part 3 Section G-1984 Precast concrete (structu

22、ral) 1.3.4.7 Cumulative tolrances. Particular attention is drawn to the fact that tolerances can be cuniulatsve, i.e. adjoining edges of two floor panel units nominally at the same level can differ lay the sum of the positive deviations on how and thickness on one unit and the negative deviations on

23、 the same d,mensions on the next unit. 1.3.4.8 Use plus and minus values. Where appropriate, give permissible deviations as both plus and minus values on a specific dimension, rather than as a deviation from a maximum or minimum value and ensure that working drawings to be used by the manufactur.er

24、give all the required dimensions and permissible deviations. DESIGN REQUIREMENTS GENERAL. The term structural precast concrete covers a wide range of sizes and shapes of units varying from large highly sophisticated prestressed units for bridges and buildinys, through singly- and mass-produced units

25、 of less si-gnificance, to a multitude of shapes of facade panel units, some with architectural finishes for buildings. The design and detailing of the shape, reinforcement, and f ixiriq are the responsibility solely of the professional engineer. However, in the field of mass-produced units, the exp

26、erience and skill of the manufacturer and the contractor are of prime irportance. This is particularly so for the many shapes and sizes of facade units normally required. In the fields of mass- produced units and relatively small units, the professional engineer is almost wholly dependent on thc com

27、petence of the contractor to manufacture particular shapes with the necessary degree of sounclliess and reliability, and also to erect and fix each unit safely. In addition to the loads for which the finished structure is deslgned 111 terms of SAI3S 01002), take account of the relative weakness of t

28、he concrete durlng its early life, and of the stresscs that will be induced during the manufacture and handling of the units. Take cognizance of the rcsults of the investigations carried out as recommended in 1.1.1 above. SABS 1200 GE has been framed to provide for, and to be applicable to structura

29、l precast concrete regardless of whether it is designed by a professional engineer employed by a client Lody, or by a firm of consulting enqineers, or by a contractor. The client or the fixm accepts responsibility for the design of his/its professaonal engineer and the contractor is responsible for

30、the designs of his professional engineer. QUALITY. Ensure that precast units, whether plain or reinforced, have been designed in araxdence with the applicable recommendations of Part I of SABS 01002), and that the quality and workmanship conform CJ the relevant requirements of SABS l200 G), and SABS

31、 1200 GE, as dpplicablr. PROCEIXJHE. See Clause 2 of Section G. PRECAUTIONS. Consult Precast Concrete in Arch.tec=) to ensure that desiqns take manufacturinq considerations into account and that correct jointing/weatherproofjng arrangemcnts, fixing, and tolerances are specified. Although some of the

32、 materials named in the section of this book that deals with cost factors are not of South African origin, the cost factors quoted are generally relevant and applicable in the riepublic of South Africa. (See also 5.2 below.) CONNECTION DETAILS. Consult Kraftschllissige Verbindungen im ertigteilb) (P

33、P l: Kc111struktio11s-Atlas, Pt. 2: Deckenverbindungen) for systematic compilations of details of precast and in-situ structural concrete connections covering columns and beams (Part 1) and floors (Part 2). The ublications qive drawings and recomnlendations regarding the application, design, and ere

34、ction of each of a large number of connections. In addition, criterla are given for the ratinq, as compared to a various connections and its respective variants in terms of its structural properties, permissible tolerances, manufacturing and measures, and outer appearance. APPLICABILITY OF OTHER c:o

35、nw The requirements of SABS 0100) are generally applicable. TEST PROCEDURES monolithic construction, of each of the suitability, advantages, disadvantages, erection qualities, required protective GENERAL. Except where otherwise specified in SABS 1200 GE or in the project specification, apply the tes

36、t procedures recommended in Part 11 of SABS 0100). QUALITY CONTROL AND OTHER CONSIDERATIONS QUALITY CONTROL. Apply the relevant recommendations of SABS 0157) to the design, process control, and quality assurance aspects of precast concrete. FAILURES. hen selecting architectural finishes and detailin

37、g precast: units, take cognizance of the failures and the case studies reported in the book Precast Concrete in rchitectizre). 1) Seep.1. 2) Structural use of concrete. 3) By A E J Morris, published by George Goodwin Ltd, London, 1978. 4) Precast concrete connection details (Part 1: Column and beam connections, Part 2: FLoor connections), published in 1978 and 1981 by Beton Verlag, Dfisseldorf (German/Enqlish text). 5) Quality management systems. ISBN 0-626-06890-8 sabr pta