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SI Unit -Dl^S^Jl 0_-° M
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General Info
I ID i Bl '
Function | Strut and-Tie
connectivity
Start STM Node [
End STM Node \~
8
1
JLJXJ
- Properties ———
Length | 315Q.Q mm Pfopertylype
Orientation | 3SQQOQ deg Non Ptestressed flanforcement Tie J^j
ReL Stiffness) 1
Property Type Name
TwForce j 2400 kN 3rd Flow Steel _^| 1 ShowDetaJ. |t
,
nTTiPKM—i ... . ,.. ,„., TrTi.r., NUTT r, ,
yp u t
iy(>fe Propciiic*
•T"^ - • ^strength —— - -
& r 300 00
Pa
. . .." , Number of Bar Layc s j 4 ^j
"Defined Types-
-• Bat Layer Oat*
|
IIV
NODE
ifffibr.
rn 4fi9\
ExS[RJt)S e teel ' " , Bar Oes^jnation
Interior Steel dpi' | NumfagrofBars
I — — — .j Nominal Diameter -111 mm
813
-^ Aiw-284mrrf
I 300 mm
Mote. Oak the 'Apply button to the tight after
ng a bar layer
Note. This tie type cannot be deleted ~
because tt has been assigned to STM g -~~
Element*
summaiy
. Total Steel Area | 2272.0
Dos* Section
Strength Reduction
•**• j Q75
~- » : Yield Force | " 5112
kH
| TensionZone Extension | 50 mm
^_j'
_
mrrf
Use Default
Controd
lie j iusl M«tTieV/idth | 7191
mm
j
• » Tip- In addition to using "Layer Number updown contol above to select
a bar layer you can ako do it by clicking a bar laiyer from the image
! tothelertorbyc£ckmgtheimageandthenpres: wig up or down
u F __i ^•Tljrl -
arrowkey
JU |1 rr,r| [ OK | Caned
Fig. 5 Results of truss analysis, dimensioning of struts and nodes, and selection of
reinforcement for ties.
The truss analysis for each load condition was then conducted. Afterwards, the reinforcement for
each tie was selected, and the dimensioning of the struts and nodes were performed. Fig. 5 shows
the results after the design was finalized. The top left display window partially shows the member
forces and stress ratios associated with the left lateral load condition. The bottom left display
window partially shows the member forces and stress ratios (i.e., the member stress intensities
normalized to the corresponding stress limits) associated with the right lateral load condition. Note
that colorized members were used to describe the level of stress ratios. The top right window is the
"Show Element Info" dialog box displaying the summary of tie B-L This dialogue box was
displayed by selecting tie B-I using the right mouse button. From that dialog box, the "Show
Detail" button was pressed to reveal the "Define Non-Prestressed Reinforcement Tie Types"
dialogue box (bottom right window) displaying reinforcing bar detail for Tie B-L
SUMMARY
Provisions for the design of D-(Discontinuity) Regions in structural concrete by the Strut-and-Tie
Method (STM) have recently been incorporated into several international design specifications.
The next step in the evolution of these provisions is to incorporate seismic design rules that address
the strength degradation of struts and nodes, ductile detailing, and how to design structures for
cyclic loading combinations. To aid designers in the use of the STM, computer-based design tools
are under development, including the CAST design tool (www.cee.uiuc.edu/kuchma/strut&tie).
ACKNOWLEDGMENTS