123. FREYSSINET C AND K SYSTEMS ANCHORAGES
C System
123.23 Internal and external Prestressing (concrete cover and anchorage distances)
The minimum distances are recalled as follows:
" Grouping on several lines
ao : minimum distance between the axes of two anchorages
ao = A (or B)* + 30 mm (*depending on the orientation of the tromplates)
bo : minimum distance between the axis of an anchorage and the concrete face.
a
a a b b
The following
must be verified:
a or/and a e" ao, b or b e"
bo
2
a b or/and ab e" 1,6 b
o
1,5 Fo
aa e"
B
f cmin
A
Dimensions in mm 3 C 15 4 C 15 7 C 15 13 C 15 19 C 15 25 C 15 31 C 15 37 C 15 55 C 15
ao = A + 30
180 180 210 280 330 390 415 450 540
minimum
ao = B + 30
140 150 180 240 280 330 350 380 450
minimum
Units
fc min. 3 C 15 4 C 15 7 C 15 13 C 15 19 C 15 25 C 15 31 C 15 37 C 15 55 C 15
MPa
23 120 140 185 250 300 345 380 420 510
bo 33 105 115 155 210 250 290 320 350 425
mm
43 105 110 140 190 225 260 285 310 375
63 105 110 135 185 220 255 275 295 345
" Grouping on one line
2 b
The following must be verified:
This arrangement concerns for example, the ancho-
b e" boo
rages in the web of a beam or segment or ancho-
b e" 1,5 boo
rages of transverse prestressing tendons in the upper
Fo
a b e"
slab of a bridge.
f cmin
boo : minimum half-thickness of the wall
Units
fomin. 3 C 15 4 C 15 7 C 15 13 C 15 19 C 15 25 C 15 31 C 15 37 C 15 55 C 15
MPa
23 90 105 145 190 230 265 300 330 400
boo 33 85 100 125 170 200 230 260 285 350
mm
43 85 95 120 160 190 220 240 260 315
63 85 95 120 160 190 220 235 255 300
23 180 210 290 380 460 530 600 660 800
33 170 200 250 340 400 460 520 570 700
2 b
mm
43 170 190 240 320 380 440 480 520 630
63 170 190 240 320 380 440 470 510 600
PAGE 1/2
b
a
b
a
a
A
B
a
b
PPC 123/23- 02.95
123. FREYSSINET C AND K SYSTEMS ANCHORAGES
K System
123.24 Internal and external Prestressing (concrete cover and anchorage distances)
ao : minimum distance between the axes of two anchorages.
ao = I (or J)* + 30 mm (*depending on the orientation of the bearing plates - see ż 112.32 to 112.33).
bo : minimum distance between the axis of an anchorage and the concrete face.
The minimum distances are recalled as follows:
a a b
The following must be verified:
a or/and a e" ao, b or/and b e"
bo
2
a b or/and ab e" 1,6 b
o
1,5 Fo
aa e"
f cmin.
fc min 7 K 13 12 K 13 19 K 13 27 K 13 37 K 13 55 K 13
in MPa 4 K 15 7 K 15 12 K 15 19 K 15 27 K 15 37 K 15
23 155 205 255 305 365 435
28 145 190 240 285 340 405
bo
in
33 140 180 225 270 325 385
mm
38 130 170 215 260 310 370
43 125 165 210 250 300 355
Note: For concrete such as fcmin > 43 MPa, refer to the K system technical
2 b
The following
guidebook, appendix 2, section 5.
must be verified:
" Lateral cover and distances between anchorage
b e" boo
axis. Grouping on one line.
b e" 1,5 boo
boo : minimum half-thickness of the wall.
Fo
a b e"
f cmin.
fcmin 7 K 13 12 K 13 19 K 13 27 K 13 37 K 13 55 K 13
in MPa 4 K 15 7 K 15 12 K 15 19 K 15 27 K 15 37 K 15
23 130 170 210 250 300 355
28 120 155 195 235 280 335
boo
in
33 115* 150* 185* 225 265* 315
mm
38 115* 150* 185* 215* 265* 300*
43 115* 150* 185* 215* 265* 300*
23 260 340 420 500 600 710
28 240 310 390 470 560 670
2 b
33 230* 300* 370* 450 530* 630*
mm
38 230* 300* 370* 430* 530* 600*
43 230* 300* 370* 430* 530* 600*
Note: The asterisks indicate the lower limit for boo whatever the upper class of concrete used.
For concrete such as fcmin e" 38 MPa and providing special plates are being used, the above values of boo can be reduced (refer to the K system technical guide-
book, appendix 2, section 5).
PAGE 2/2
b
a
a
b
PPC 123/23- 02.95