IRC 78 Part-2-2020 - Amendment No. 1 - June 2022
IRC 78 Part-2-2020 - Amendment No. 1 - June 2022
IRC 78 Part-2-2020 - Amendment No. 1 - June 2022
NOTIFICATION NO. 53
Amendment No.1/IRC:78(Part-2)/June, 2022 (Effective from 1st September, 2022)
To
IRC:78-2020 (Part-2 ) Code of Practice for Limit State Design of Foundations
4 3.2.3
Fig 4
(Page No. 8)
5 4.3 The vertical ground resistance shall For materials, the vertical ground
(below Table 4) be computed always using Set 1 value resistance shall always be computed
(Page No. 13) only for materials, in all combinations using Set 1 value only in all
for piles subjected to both combinations for piles subjected to
compressive and tensile forces. both compressive and tensile forces.
6 4.4.1 Short pile foundations only Short pile foundations only,
Line 1
(Page No. 14)
7 4.5.4 CR 6 1.50,1.35,1.30 CR 6 1.90,1.76,1.70
Table 8
(Page No. 17)
8 4.8.1 Para 1 In order to arrive at the design tensile In order to arrive at the design tensile
(Page No. 21) resistance of an isolated pile, the load resistance of an isolated pile, the load
combinations as per table B.4 of combination as per Table B.4 of IRC:6
IRC:6 shall be followed. and Table 10 under Clause 4.8.3.1 of
this code shall be followed.
14 5.1 Para 2, Clause 5.3 of this code. Clause 5.4 of this code.
Line 2
(Page No. 25)
15 5.9.2 Add at the end of 1) For foundation resting over rock the resisting
(Page No. 28) factor shall be taken as mentioned in Clause
5.6.2.
Explanatory note
16 (Page No. 34) ( D) Foundation Resting on Rock (D) Foundation Resting on Rock (Cases as
mentioned under (A))
17 2.5 (c), Table 4 ≥3 ≥5
(Page No. 40)
18 2.10 (A) 4) Calculation of pile FOS from Dynamic 4) Calculation of pile FOS from Dynamic
(4) tests tests
(Page No. 43) Taking tests conducted at two locations Taking tests conducted at two locations
Combination 1 Combination 1
DL:LL 50:50 = 1.50 x 1.425 = 2.13 DL:LL 50:50 = 1.90 x 1.425 = 2.70
DL:LL 70:30 = 1.50 x 1.395 = 2.09 DL:LL 70:30 = 1.90 x 1.395 = 2.65
Combination 2 Combination 2
DL:LL 50:50 = 1.50 x 1.15 x 1.70 =2.93 DL:LL 50:50 = 1.90 x 1.15 x 1.70 = 3.71
DL:LL 70:30 = 1.50x 1.09 x 1.70 = 2.77 DL:LL 70:30 = 1.90x 1.09 x 1.70 = 3.52
19 2.10 (B) 4) FOS using Dynamic tests 4) FOS using Dynamic tests
(4) Combination 1 Combination 1
(Page No. 43) DL: LL 50:50 = 1.50 x 1.25 = 1.88 (88%) DL: LL 50:50 = 1.90 x 1.25 = 2.38 (88%)
DL: LL 70:30 = 1.50 x 1.29 = 1.94 (93%) DL: LL 70:30 = 1.90 x 1.29 = 2.45 (93%)
On Ground Strength 1.50 On Ground Strength 1.90
Combination 2 Combination 2
DL: LL 50:50 = 1.50 x 1.0 x 1.7 x 0. 85 = 2.16 DL: LL 50:50 = 1.90 x 1.0 x 1.7 x 0.85 =
(74%) 2.74 (74%)
DL: LL 70:30 = 1.50 x 1.0 x 1.75 x 0. 85 = 2.16 DL: LL 70:30 = 1.90 x 1.0 x 1.70 x 0.85 =
(78%) 2.74 (78%)
Ground strength alone 2.16 Ground strength alone 2.74
Factor of safety remains 1.60 and above Factor of safety remains 1.60 and above for
for normal methods and for dynamic normal methods and for dynamic methods
methods it will be 2.20. Target for normal it will be 2.74. Target for normal methods
methods is 2.0 for normal loading: 25% is 2.0 for normal loading: 25% of over
of over stressing when compared to stressing when compared to normal load.
normal load. Hence can be accepted for Hence can be accepted for ground
ground resistance factor. resistance factor.
21 3.11 Last Hence Resistance Factor of 1.20 and 1.1 Hence Resistance factors of 1.20 and 1.00
Para Line 1 can be taken. can be taken.
(Page No. 47)