Dynamic Specs

8/13/2019 Dynamic Specs

1/6

597088~ABLE 1-1Dynamic spring Ktfor use Eq. 1-1. Obtain Si factors from Table 1-2.Values shown are stat c values which must be multiplied by a factor 11;which mayobtained from Fig, 1-2, Note that 2L = base length and 28 = base width with Lparallelto X axisand 8 paralleltoY axis,- -,-,-For re


2/6

For sliding damping p.1r:1l1elto Y axIS In range of O::i a. ::i 1.5

TABLE1-2SIfactors for computering KIof Table'I-1Mode Applicable

S: = 0.8S: ~ 0.73 + 1.5~(J.)0

Horizontal: S, = 2.2~S, = 4.5(J,)0)~

J. ::i 0.02J. > 0.02J.::i 0.16J. > 0.16

Yerti.::al:

Rocking: s.. = : ..~S.. = 3.2(B; L)IS., = 3.2S, = 3.8+ 10.7(1- B. L)IO

BL ~ 0.4B,:L > O.~All B, LAll B: Lorsion:

J, - arQ/(4L)' when: 2L - lenglh or ba>c:;Area- 28 x 2L forsolid rectangle.

TABLE 1-3 Damping constants for computing the damping coefficient Cl

For vertical damping in range of 0 ;;;a, ;;;1.5;..= ~.. XI a.R)Xl.. (a,R)zX,+ X.. exp (-a,R). p1 0..1

For R > 10 use i., ' )':110,11 ... O.OOIR) For a, > 1.5 use c: so pVL.oA

::A.', .~r .o. .

;, - ~ ' X, ... (c,R)X,... (a.R) X,... X.exp(-a,R)P~..-I

App. I, Pg. 2/6

;'eL1L R X, Xl X) X.

0.9716 -0.0500 0.0520 -0.06603.42 1.2080 -O.l 0.0385 -0.2515 'LA=-I1;(1- 1 ).: 1.0900 -0.0025 0.0012 0.0000 A ..actual base area6 1.2285 -0.0359 0.0024 0.151510 1.3112 -0.0285 0.0011 0.4388

L B ' ' R X. X, X, X.U720 -0.6140 0.2118 -0.7062: 1.0200 0.0000 0,0000 0.0000.1 L7350 -0.2915 00288 -0.495010 1.8OJO -0.1273 0.0051 0.7960


3/6

T LE 1-3 (continued)For R > 10use i.n,= ;'>110,(1 ... O.00:5R)

For sliding damping paralld 10 X a.\is use Ihe [allowingFor IJ. > 1.5 use e, = pV,A

For rocking d:lmping use0;;; LiB ;;;3 use c. = i. pI ,A LlB> 3 use e, = pV,A

597088

AL~

i.,; = --2- = a.X, + a;X2 + Cl:X)+ a:X.pVuI.

LIB= Ri~. = rocking aboul X :lxis

X,1&25~IO

0.03371.07571.6-165i~, = rocking aboul Yaxis

,3~&5

0.03370.nS3O,6;IiS1.01238

(same :ISi,..).1477 -1.03691.6257 - 1.68~1.5620 -2.02270.50-16 - 1.5762ForR~loo(;;:o:,);',,=1

0,28490.-18950.63820.6052

For torsion d:lmping use. c, ':), -, R/..= --;- = a XI - a X2...a X ...X. lan -pl~ a.

X2 X) X.

1.1477 -1.0369 0.2849-0.4.;92 -0.1621 0.1550-1.52017 0.8516 -0.26

U R x, x: x) x.-O,S: 0.5277 -0.1:1013 0.02142 0.89':5 -0.2226 -0.2 -0,061:3 1.6330 -0,8238 0,1156 -0.096201 2,6028 - 2,052 0,5312 -0.1070> 100 ;., = 1,0


4/6

:.~ ,:-,, ' ,:' '...IGUR 1-1 Factor Ja= A/(4L2) for several geometrical shapes. Note axis

o~entation in all cases and length ,= 2L and width = 28.Circle~V \

yA = 0.7854{2L :AJ. = ---; = O,78S~4L

Triangle

1.732L:A=-,:-1.732\ = 0.2\6J. =--g

Semicircle Ellipse

:=28J. = 0.3927 ~L:.-I= 7:BL= -2J.=0.3926

App. I, Pg. 4/6

~

~

t. .~

Square Rectangle nn IfB-1 t xxIiY Y

L :.- '= IB B - -A = 4L: .-1= L:J = I J.=0.50


5/6

K-1:= K: 0.5

-0,5 0

1.5

LiB = 4LIB = 1and 2LiB = I

LIB= 6

L.iB=:r.:

1.5

a) Vertical 1: factors. Note these are dependent on Poisson s ratio1 Use P =0,,5 for saturated clay and Jl = 0.33 for all other soil.

~LOC

0

-p=0.5- - - I = 0.330.5 ~ ~

597088

fi\ l

FIGURE 1-2 The T \Iactors to convert static springs of Table 1-2 t o dynamic valuesas K. = T \K..Curves condensed from Oobry and Gazetas 1985).

wBa. = V.


6/6

K.; 0.5'/.. = K..;

Ko'1.= K;

...:.:----- :=....r ..., :,AIl LIBLIB=t.:j J - -2S LIBs.S -------'I..---'I.,

00 0.5 \.0 \.5wBa --.- y.(b) Rocking I.. and I., factors.

1.5

\.0

'I,0.50 0.5 \.0wB

a.=v:(r) Sliding I, and torsion . factors. All torsion factors

arc I. < I.

igur 1-2 (continued)

LIB=4LIB =2LIB = t all pLIB =4LIB = t

1.5

t::iJ\L~

App. I, Pg. 6/6

/~,

~..~. l: t ;.-= 1 :::,lo ::;;

( ,.t:,,-1.. '~w

Documents

Dynamic Specs