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1、- STD-IS0 Li8bb-ENGL L770 M Li851703 b88230 770 I NTE RNATI ONAL STANDARD IS0 First edition AMENDMENT 2 1990-08-01 1996-1 2-1 5 Mechanical vibration and shock - Vibration of buildings - Guidelines for the measurement of vibrations and evaluation of their effects on buildings AMENDMENT 2 Vibrations e
2、t chocs mcaniques - Vibrations des btiments - Lignes directrices pour le mesurage des vibrations et valuation de leurs effets sur les btiments AMENDEMENT 2 This material is reproduced from IS0 documents under International Organization for Standardization (SO) Copyright License number IHCIICCI1996.
3、Not for resale. No part of these IS0 documents may be reproduced in any form, electronic retrieval system or otherwise, except as allowed in the copyright law of the country of use, or with the prior written consent of IS0 (Case postale 56,1211 Geneva 20, Switzerland, Fax +41 22 734 10 79), IHS or t
4、he IS0 Licensors members. Reference number IS0 4866:1990/Amd,2:1996(E) COPYRIGHT International Organization for Standardization Licensed by Information Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services IS0 4866:1990/Arnd.2: 1996(E) F
5、oreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a te
6、chnical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters
7、of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Amendment 2 to IS0 4866:1990 was pre
8、pared by Technical Committee ISO/TC 108, Mechanical vibration and shock, Subcommittee SC 2, Measurement and evaluation of mechanical vibration and shock as applied to machines, vehicles and structures. Annex E is for information only. O IS0 1996 All rights reserved. Unless otherwise specified, no pa
9、rt of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case Postale 56 CH-1 21 1 Genve 20 Switzerland Printed in
10、 Switzerland II COPYRIGHT International Organization for Standardization Licensed by Information Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services IS0 STD-IS0 48bb-ENGL 1790 V851703 Ob88232 743 W IS0 4866: 1990/Amd.2: 1996E) Mechanic
11、al vibration and shock - Vibration of buildings - Guidelines for the measurement of vibrations and evaluation of their effects on buildings AMENDMENT 2 Page i Change the last sentence to: Annexes A to F of this International Standard are for information only Page 17 Add the following annex as annex
12、E and change the present annex E to annex F. 1 COPYRIGHT International Organization for Standardization Licensed by Information Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services STD-IS0 48bb-ENGL 1770 4853903 Ob88233 b8T = IS0 4866:1
13、990/Amd.2:1996(E) 0 IS0 Annex E (informative) Vibrational interaction between the foundation of a structure and the soil E.l General When vibration measurements cannot be made on the foundation of a structure or inside a building, IS0 4866 allows that measurements be made on the ground surface outsi
14、de. It may also be necessary to predict the response of a building not yet constructed. In both cases there is a need to understand the dynamic interaction between a building and the ground. In the first case, the most suitable position outside the building for measurement and the relationship betwe
15、en the signal at that position and that on the building foundation need to be established. In the second case, the response of the foundation of the building may be expected to follow closely the motion of the ground in contact with the foundation unless interaction is significant. This annex seeks
16、to indicate the nature of such an interaction and suggests procedures which allow it to be taken into account. Figure E.l illustrates the notation which will be used in this annex in terms of the peak amplitude, u, of a travelling wave passing across a foundation (u can be the displacement, velocity
17、 or acceleration amplitude of the sinusoidal wave). Free-field amplitude is denoted by uo, amplitude in the base of the foundation by UF, amplitude at an arbitrary position in the structure by ust, and on the soil surface near an existing building by UN. Far from the structure, U N = UO. Soil-struct
18、ure interaction analysis is concerned generally with the relationship between free-field motion and structure motion, that is ust/ug and, in particular, UF/UO = rg. The important ratio UF/UN = I-N is given by the more sophisticated procedures which also address the problem of soil response involving
19、 the variation of vibration amplitude with depth. 2 COPYRIGHT International Organization for Standardization Licensed by Information Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services STD-IS0 qBbb-ENGL 1990 4851903 Ob88234 5Lb IS0 486
20、6:1990/Amd.2:1996(E) Source I Distance Symbols: u u0 is the free-field amplitude; U N is the amplitude on the soil surface near an existing building; U F is the amplitude in the base of the foundation; uSt is the amplitude at an arbitrary position in the structure. ro = UF/UO YN = UF/UN is the displ
21、acement, velocity or acceleration amplitude of the sinusoidal wave; Figure E.l - Notations, illustrated at a horizontally propagating wave 3 COPYRIGHT International Organization for Standardization Licensed by Information Handling Services COPYRIGHT International Organization for Standardization Lic
22、ensed by Information Handling Services STD-IS0 48bb-ENGL 1990 q851903 Ob88235 452 IS0 4866:1990/Amd.2:1996(E Q IS0 E.2 Theoretical considerations Soil-structure interaction influences the dynamic response of all structures to some degree. Only a rigid building bonded to rigid ground would respond in
23、 the same way as the ground. In reality, the ground does not have an infinite rigidity and may provide a mechanism for the radiation and dissipation of energy. Hence it can be thought of as acting as a spring and dashpot system or a series of such systems just below the foundation. The degree to whi
24、ch soil-structure interaction is a significant aspect of structural response depends on the dynamic parameters of the structure and of the ground, in particular on the natural frequencies of the structure and the shear stiffness of the ground. When considering relatively stiff low-rise buildings (lo
25、w rise = 6 m to 7 m high), the problem may be examined as the vertical response of a rigid mass on a spring and a dashpot adjusted to match the analytical solution with the ground as semi-infinite isotropic and homogeneous elastic halfspace. Such simple concepts suggest that the maximum amplificatio
26、n to be expected in the vertical direction is not likely to exceed 2. Rocking and sliding modes can also be explored in a similar manner and suggest that somewhat higher magnifications can be theoretically achieved in most cases. However, vertical amplification is surely limited because energy captu
27、red by the structure from the passing wave is reradiated into the ground thus damping the amplitude response. Full consideration of soil-structure interaction should take account of the layering of the soil, the variation of shear stiffness with depth, the effects of building load on soil stiffness,
28、 the effect of shear strains on soil stiffness, the geometry of the foundation, and foundation embedment, as well as the frequency content of the excitation. Dynamic soil-structure interaction is one of the central problems in earthquake engineering, and over the last two decades methods of analysis
29、 have been highly developed, mainly for the nuclear industry, giving rise to a vast literature (see references 1391 to 451). Refined analysis has also been used for wind and man-made loading and some simplified rules have been derived (see references i461 and 471). These advanced analytical methods
30、can be grouped into two classes: a) the direct method, whereby the soil and structure are treated together; the ground may be represented by finite elements, lumped parameters or both (hybrid models); b) the substructure method, whereby the response of the ground and structure are calculated as sepa
31、rate systems with a separation between ground and structure to which springs and dashpots or stiffness functions are applied. Another approach is the response spectrum, widely used in earthquake engineering and other shock loading (see reference 481). It can be adapted to take some account of soil-s
32、tructure interaction by reducing the natural frequency assessed for a structure on soils of low stiffness. The effects of soil response can be allowed for, in part, by using design response spectra which vary according to the shear modulus depth profile of the soil. Generally, the closer the frequen
33、cy of the excitation is to the natural frequency of a building or building element the greater will be the response. Earthquakes, with low frequencies of 0,5 Hz to 8 Hz, will tend to excite the lower natural frequencies of buildings; man-made excitation is generally at higher frequencies and tends t
34、o excite the structural elements of a building. Furthermore, the range of vertical frequencies of building elements (6 Hz to 40 Hz) lies in the range of man-made excitation, leading to the relatively large bending responses which have been observed in ceilings (see reference 491). E.3 Relationship b
35、etween vibration at the ground surface and at the foundation There are difficulties associated with measurements on the ground near the building, for example: - the measuring point is usually remote from the positions of interest within the structure; - there are more uncertainties in coupling the t
36、ransducer to the ground than in fixing it to a building part; - the soil near a building is often disturbed; - vibration amplitudes near a building may change with distance from the building as a proportion of the wavelength. 4 COPYRIGHT International Organization for Standardization Licensed by Inf
37、ormation Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services IS0 4866:1990/Amd.2:1996(E) 0 IS0 The direct methods for analysis of soil-structure interaction are expensive and need detailed knowledge of soil properties, however, they ca
38、n give some guidance on the following factors influencing r . a) The amplitude of vibration may be affected by reflection at the front of the foundation (with respect to the travelling wave) and decreased at the rear side by dissipation and front side reflection. Theses effects depend on the foundat
39、ion size, depth and excitation wavelength. b) Where the propagation behaves like a surface Rayleigh wave (which is usual for distant sources), the amplitudes decrease with depth (see, for example, figure E.21, so deeper foundations pick up less motion. c) Strong earthquake motions are usually modell
40、ed as vertically propagating horizontally polarized shear waves with amplitudes increasing as the waves pass upwards from high rigidity. So again, deeper foundations may pick up smaller vibration. Such complexities preclude a definitive set of rules relating r and ro to the category of structure and
41、 character of excitation, but both measurements (see reference 1501) and theoretical studies indicate that in most situations of man-made excitations the value of rN is likely to be unity or less. This has been supported by results of a questionnairel) which has indicated that for vertical motion wi
42、thout regard to frequency, N was in the range 0,3 to 0,6. The maximum magnification recorded was in the horizontal response and amounted to a 13 YO increase. Histograms of the replies to the questionnaire are given in figures E.3 and E.4. This general reduction of vertical vibration on the foundatio
43、n as compared with that on the soil surface near a building may not hold in cases where there is a marked rocking response to continuous vibration. As for preferred positions of measurement near a building, it is suggested that these positions should be less than 2 m or 1/10 of the dominant waveleng
44、th away from the building. 1) The questionnaire contained various ground conditions as well as various types of vibration excitation. 5 COPYRIGHT International Organization for Standardization Licensed by Information Handling Services COPYRIGHT International Organization for Standardization Licensed
45、 by Information Handling Services STD-IS0 LIBbb-ENGL 1990 i851903 Ob88237 225 IS0 4866:1990/Amd.2:1996(E) hl5 t LR is the Rayleigh wavelength. Figure E.2 - Variation of vibrational amplitude uZ with depth z of a Rayleigh wave 6 COPYRIGHT International Organization for Standardization Licensed by Inf
46、ormation Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services - VI c + 10 L 3 VI m E9 S 8 r O L W n I x v 57 U 01 L U 6 5 4 3 2 1 O A VI c + i6 L 3 VI E5 54 L O L W n - x “ g 3 U W L U 2 1 STD-IS0 48Lb-ENGL 1990 M 4851903 Ob88238 Lb1 I
47、0,2 IS0 4866:1990/Amd.2: 1996(El 0.4 0.6 0.8 1 1.2 f N Figure E.3 - Frequency distribution of r (vertical direction of vibration) O 0.2 0.4 0.6 0.8 1 1.2 Figure E.4 - Frequency distribution of rN (horizontal direction of vibration) 7 COPYRIGHT International Organization for Standardization Licensed
48、by Information Handling Services COPYRIGHT International Organization for Standardization Licensed by Information Handling Services STD-IS0 98bb-ENGL 1770 m 4853703 b88239 OT m IS0 4866:1990/Amd.2: 1996E) Page 18 Add references 391 to i501 to annex F. i391 i401 141 I i421 i431 1441 i451 i461 i471 14
49、81 i491 501 0 IS0 NEWMARK, M. and RosENBLUTH, E. Fundamentals of earthquake engineering. Prentice Hall, 1973. RICHARD, F.E., HALL, J.R. and WOODS, R.D. Vibrations of soils and foundations. Englewood Cliffs, NJ, 1970. WOLF, J.P. Dynamic soil structure interaction. Prentice Hall, 1985. CLOUGH, R.W. and PENZIEN, J. Dynamics of structures. McGraw Hill Corp., New York, 1975. WARBURTON, G.B., RICHARDSON, I.D. and WEBSTER, J.J. Forced vibrations of two masses on an elastic halfspace. Transactions ASME, March 1971. HOLZLOHNER, U. Dynamically loaded buildings on
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