ANSI ASCE 3-91 9-91-1991 Standard Practice for Construction and Inspection of Composite Slabs.pdf

1、SPECIAL NOTICE The material presented in this publication has been prepared in accordance with recognized engineering principles. This Standard and Commentary should not be used without first securing competent advice with respect to their suitability for any given application. The publication of th

2、e material contained herein is not intended as a representation or warranty on the part of the American Society of Civil Engineers, or of any other person named herein, that this information is suitable for any general or particular use or promises freedom from infringement of any patent or patents.

3、 Anyone making use of this information assumes all liability from such use. ASCE 3 91 0759b00 0022979 TL1 ANSI / ASCE 3-91 AM / ASCE 9-91 AW Approwed beer“ li, 1992 American Society of Civil Engineers Standard for the Structural Design of Composite Slabs ANWASCE 3-91 ANSI Approved December 11,1992 S

4、tandard Practice for Construction and Inspection of Composite Slabs AWASCE 4.81 ANSt Approved December 11,1992 ASCE 3 71 m 0757600 0022980 733 m ANSI / ASCE 3-91 ANSI / ASCE 9-91 ANSI Approved December 11,1992 American Society of Civil Engineers Standard for the Structural Design of Composite Slabs

5、ANSVASCE 3-91 ANSI Approved December 11,1992 Standard Practice for Construction and Inspection of Composite Slabs ANSVASCE 9-91 ANSI Approved December 11,1992 Published by the American Society of Civil Engineers 345 East 47th Street New York, New York 1 O01 7-2398 ASCE 3 91 m 0759600 0022983 b7T m A

6、BSTRACT American Society of Civil Engineers Standard for the Structural Design of Composite Slabs, ASCE Standard Practice for Construction and Inspection of Composite Slabs (ASCE 3-91 and ASCE 9-91 respectively) presents standards for the structural design and testing of composite slabs and for good

7、 construction dards are included. The “Standard for the Structural Design of Composite practice and inspection procedures. In addition, commentaries on both stan- Slabs” (ASCE 3-91) and its “Commentary” cover such topics as loads, construc- tion stage, strength design, service load design, test proc

8、edures, and test results evaluation. The “Standard Practice for the Construction and Inspection of Composite Slabs” (ASCE 9-91) and its “Commentary” discuss such topics as damage control, connections, concrete placement, shore removal, holes and hole reinforcement. These standards are written in suc

9、h a form that they may be adopted by reference in a general building code. Library of Congress Cataloging-in-Publication Data Standard for the structural design of composite slabs: ANSVASCE 3-91, ANSI approved December 1 1, 1992; Standard practice for construction and inspection of composite slabs:

10、ANSVASCE 9-91, ANSI approved December 11,1992. p.cm.-(ASCE standard) SBN 0-87262-954-6 Includes bibliographical references and index. desian-Standards-United States. I. American Societv of Civil Enaineers. l. Composite construction-Standards-United States. 2. Structural II. Tae: Standard practice fo

11、r structural design of comphsiteslabs. 111. Series: American Society of Civil Engineers. ASCE standard. 0 TA664S72 1994 624.1 772-dc20 94-3855 CI P Photocopies. Authorization to photocopy material for internal or personal use under circumstances not falling within the fair use provisions of the Copy

12、right Act is granted by ASCE to libraries and other users registered with the Copyright Clearance Center (CCC) Transactional Reporting Service, .provided that the base fee of $2.00 per article plus $.25 per page copied is pald directly to CCC, 27 Congress Street, Salem, MA 01970. The identification

13、for ASCE Books is 0- 87262-954-6/94 $2.00 + $25 Requests for special permission or bulk copy- mg should be addressed to Permlsslons or in Appendix D, the length of repeating embossment pattern, in. appropriate effective section modulus for either positive or negative bending, in.3/ft. of width secti

14、on modulus of concrete, in.3 thickness of steel deck exclusive of coating, in. component of tensile force resisted by bottom horizontal elements of steel deck in general strain analysis, lbs. per ft. of width deck element tension forces with i = 1 to 3, lbs. component of tensile force resisted by to

15、p horizontal elements of steel deck in general strain analysis, lbs. per ft. of width T, = v, = V“, = ve2 = v, = v, = W= W= W, = W,= W,= W,= we = W, = W, = W, = W, = W, = W, = wUo= wues = x= Y, = component of tensile force resisted by web elements of steel deck in general strain analysis location of

16、 resultant force is assumed to be at middepth of web elements), lbs. per ft. of width maximum experimental shear at failure obtained from laboratory tests (not including weight of slab), lbs. per ft. of width shear-bond capacity corresponding to a lower usage compressive strength of concrete, lbs. p

17、er ft. of width shear-bond capacity from laboratory test compressive strength of concrete, lbs. per ft. of width nominal shear-bond strength, lbs. per ft. of width factored shear force, lbs. per ft. of width wind load perpendicular to slab, psf average width of embossment, in. computed uniform dead

18、load, (Wdc + W, + concrete dead load including additional weight of concrete due to deck deflection, steel deck dead load, psf superimposed uniform dead load, (additional dead load applied to slab exclusive of W.), superimposed uniform live load, specified by general building code, but not greater t

19、han W,. or Wlf, psf uniform construction live load, 20 psf (1.0 kN/mZ) permissible superimposed uniform live load for flexure, psf permissible superimposed uniform live load for shear-bond, psf average rib width, (C, - B, + BJ2, in. roof live loads (see 4.11 of ASCE 7 3), snow loads, or rain loads,

20、except ponding, weight of slab, (W, + W i.e., the longitudinal strains of concrete and steel at any section transverse to deck corrugations are proportional to the distance of fibers from composite neutral axis. (b) Stresses are proportional to strain in both concrete and steel at service loads. (c)

21、 The entire steel cross section shall be utilized except as reduced by holes. (d) Moment of inertia, I, used in deflection calculations shall be taken as-the average of those of the cracked, I, and uncracked sections, I, using design depth of slab. Formulas for flexural section properties and moment

22、s of inertia are given in Appendix B. 2.3.2.2 - Deflection limitations. Consideration shall be given to both immediate and long-term loading. Deflection provisions apply to composite slabs of all categories, and all calculated maximum deflections shall be based on the assumptions of Section 2.3.2.1.

23、 Maximum allowable computed deflections are listed in Table 2.2. The additional deflection caused by creep shall be calculated by multiplying the immediate deflection due to the sustained load by the factor: X = 2 - 1.2(A,IAW,) 2 0.6 (2-15) 2.3.3 - Special design considerations 2.3.3.1 - Control of

24、shrinkage and temperature effects. Minimum control of shrinkage and temperature effects shall be in accordance with the following: Transverse reinforcement bars having a yield strength of at least 60,000 psi (400 MPa) or welded wire fabric shall be provided. Area of this reinforcement shall be equal

25、 to 0.00075 times the area of concrete above the steel deck but not less than 0.028 sq. in. per ft. of width (60 mm2 per m of width). Wires welded directly to top of the deck (transverse to corrugations) for the purpose of providing shear transfer shall be considered for shrinkage reinforcement. 2.3

26、.3.2 - punching Shear. Punchhg shear due to concentrated point loads shall be considered. The general procedure given in Section 11.12.2 of the AC1 Building Code Requirements for Reinforced Concrete, AC1318 2 shall beused, with the following modification. The depth of concrete over top corrugation o

27、f deck, h, shall be considered as effective depth for punching shear calculations, and nominal shear stress carried by the concrete shall not aced 2 E (/a . 2 Only top half of supporting Jpko., -I, measurements shall be taken on an interior rib and at edges of specimen. dd = overall depth of steel d

28、eck profile, P, = length of span or shored span, ft. P, = length of shear span, in. S = center-tocenter spacing of shear transfer devices, in. t = thickness of steel deck exclusive of coating determined from specimens used to obtain material properties, in; for cellular decks, each sheet shall be me

29、asured. h, = out-to-out depth of slab at failure crack, in. P, = slab overhang at supports, in. in. Dimensional characteristics of shear devices, such as for embossments, the embossment length, width, depth, spacing, shape configuration, and general variation in depth and size shall be recorded - Se

30、e Appendix C. 10 Unit width of slab in SI units shall be consistent with SI units for other terms. ASCE 3 91 m O759600 002300L Obb m (b) Material properties: f,= compressive test cylinder strength of concrete at time of slab testing, psi, according to ASTM C39 4 f, = measured yield strength of steel

31、, psi, ASTM A370 4 f, = measured tensile strength of steel, psi, ASTM A370 4 The percent elongation of steel coupon by ASTM A370 4, the steel specification and grade and other material properties shall be recorded. (c) Unit loads: W,= steel deck dead load, psf W,= concrete dead load including additi

32、onal weight of concrete added due to deck deflection, psf (d) Construction conditions: steel surface coating and condition - if galvanized, state ASTM type of coating used and whether chromate or other conversion coating was used, and if so what type; if painted, state type of paint; state any surfa

33、ce deterioration or weathering of the coating; shoring; concrete mix design and date of casting; type and location of steel welded wire fabric; and concrete cylinder air dry density at time of testing. (e) Test data: A brief description of significant events during testing, including test date, shal

34、l be recorded along with an identification of the failure mode and details of failure. The load P, the engineer, and the technician responsible for testing shall be recorded. In addition, the following shall be recorded: - midspan load-deflection measurements, A, load and end-slip measurements, load

35、 at first observable crack, and for cellular sections - thickness of each component element, number of rows, spacing, and type of fastening between components. 3.2.3 - Scope of tests 3.2.3.1 - Shear-bond tests. To develop m and k values of Section 2.3.1.5.1, the following procedures shall be used: (

36、a) Number of slab specimens shall be adequate to cover range of variables involved and to provide sufficient data for design in accordance with these criteria. (b) Tests shall be conducted on each deck profile for which design values are needed. Tests shall be conducted on each design thickness for

37、each profile or on a combination of thicknesses as indicated in Section 3.2.4.2. (c) For cellular decks, the thickness of the bonded formed section shall be used in Section 3.2.4.2, applying the limit indicated in (b) above. In lieu of performing the test series, the 4 value used in determining the

38、superimposed load capacity for a system using only cellular deck sections with shear- bond governing shall include the bottom element of cellular decks provided that the results from a minimum of two tests indicate that a shear-bond strength lower than the predicted does not exist. In the event that

39、 the confirmatory tests are lower than the predicted, then the entire test series shall be performed. The designer shall choose to perform the entire test series for m and k values. (d) Tests shall be made to determine the effects of all surface coatings or finishes to be used on a given deck profil

40、e. In lieu of testing all surface finishes, the shear-bond strength shall be obtained from tests of a coating demonstrating a lower strength, provided that verification of a coatings lower shear-bond strength is found from a minimum of two comparison tests. (e) Tests using specimens made with lightw

41、eight structural concrete shall be used to establish values for other types of concrete having equal or greater densities, provided that at least two comparison tests indicate that shear-bond strength is lower for those slabs containing lightweight concrete. (f) Tests shall be made on at least two s

42、pecimens in each of two regions, A and B as defined in Table 3.1, to develop shear-bond data. Region A defines specimens with small slab depths, h, and/or relatively large shear spans, k“i, whereas Region B defines specimens with large depths and/or relatively small shear spans. (g) When tests in ei

43、ther of the two regions of Table 3.1 consist of only two composite slab specimens, see Section 3.2.4.2(b). 11 ASCE 3 91 0759600 0023002 TT2 (h) For decks on which spacing of shear transfer devices, S, varies from one deck section to another, a series of tests to determine m and k is required for eac

44、h spacing. (i) Tests are not required for all concrete compressive strengths. For those cases where the usage strength of concrete is lower than that tested, the shear-bond strength shall be prorated according to: For those cases where usage strength of concrete is higher than that tested, the shear

45、-bond prediction in Section 2.3.1.5.1 shall be used to amve at an adjusted capacity for changes of f, not exceeding 1500 psi (10 MPa). Strength of concrete for those specimens tested shall not be less than 2500 psi (17 MPa). 3.2.3.2 - Flexural tests. For decks deeper than a nominal 3 in. (75 mm) or

46、formed from steels with low ductility having a ratio fJf, less than 1.08, and a total elongation of less than 10 percent for a 2-in. (50 mm) gage length or less than 7 percent for an 8-in. (200 mm) gage length tested in accordance with ASTM A370 4, a minimum of three representative tests shall be co

47、nducted to establish the applicability of the design moment (Eq. (2-13) or the general strain analysis) for the deck in question, (see Section 3.2.4.3). For those cases where Eq. (2-13) does not apply, a minimum of three representative tests shall be performed. The specimens tested shall cover the m

48、inimum and maximum reinforcement ratios used in actual construction. 3.2.4 - Test result evaluation 3.2.4.1 - General. Evaluation of results from tests developed in Section 3.2.3 shall be performed to establish design expressions required for application of provisions of Chapter 2. 3.2.4.2 - Shear-b

49、ond. To evaluate the test results for shear-bond strength, the following procedure shall be used: (a) A plot of Ve/bdpm versus pd/Q:fi as shown in Figure 3.2 shall be developed for each representative steel deck profile category outlined in Section 3.2.3. l. A shear-bond line, using the required test data, is then established for each plot to determine slope, m, and ordinate intercept, k, , of the line. Computation for d is based on the depth at the failure crack, h,. X= e;q* Figure 3.2 - Typical shear-bond plot showing the reduced regression