Project 1

Aim: - To design the raft foundation of the bridge underpass for the given dimension. All tye load calculation shall be done according to IRC-6 and the structure is analyzed for live load by effective width method for design.

Combinations for ULS, SLS rare & quasi-permanent are also needed to be done.

Design Data
No. of cells					=	1
Clear Span					=	12.00	m
Clear Height at the outer edge					=	5.50	m
Clear Height at the median edge					=	5.50	m
Width of Box					=	12.50	m
Carriage Width					=	11.50	m
Width of crash barrier					=	0.00	m
Width of footpath/safety kerb					=	0.00	m
Width of Haunch					=	0.20	m
Depth of Haunch					=	0.20	m
Thickness of Wearing coat					=	0	m
Thickness of fill over top slab					=	1.5	m
Depth of Top Slab					=	0.600	m
Depth of Bottom Slab					=	0.650	m
Depth of External Vertical Wall					=	0.600	m
Safe bearing capacity					=	80.00	KN/m^2
Spring Constant		Bowles book : 40 x FS x SBC (FS=2.5)			=	1066.667	KN/m
Setellement					=	0.075	m
Density of concrete					=	25.00	KN/m^3
Bulk Density of soil					=	20.00	KN/m^3
Density of submerged soil					=	10.00	KN/m^3
Density of Profile corrective course					=	22.00	KN/m^3
Density of fill					=	20.00	KN/m^3
Coefficient of active earth pressure					=	0.5
Length of the box considered for design					=	1	m
Design Parameter
Grade of Concrete					=	M30
Grade of Steel					=	Fe 500	D
Clear Cover for Top slab					=	45	mm
Clear Cover for Walls					=	45	mm
Clear Cover for Bottom slab					=	75	mm
E of concrete					=	31000	Mpa
Load Calculations
Self wt of bottom slab per meter square						=	20.00	kN/m2
Self wt of top slab per meter square						=	15.00	kN/m2
Self wt of abutment wall per meter length						=	165.00	kN/m
Self wt of abutment wall per meter square						=	12.50	kN/m2

STAAD-Pro modeling:-

The box is modeled as a plane frame structure taking the center line dimensions of the structure in STAAD-Pro. As the length of the box underpass is comparatively more than its width so the under-pass will be analyzed for unit length and then the design will be implemented to the entire structure. Since the soil is fully resting on soil, the discrete spring supports are provided below the base slab to model the earth pressure. The stiffness of the soil springs is calculated based on a sub-grade modulus of the soil available at the base. The size of the members is assigned as per assumptions.

MODEL:-

Properties:-

The sizes of the top slab, sidewalls & bottom slab are assumed and provided using the properties tab in STAAD-Pro.

Materials:-

Supports:-

The supports are provided at the bottom of the foundation. The KFY values are calculated depending on the distance between the supports. Half of the distance on either side of the support is determined & KFY values for that distance are calculated. The horizontal release is also provided in support1.

Load calculation:-

Dead Load:-

The dead load on the structures is calculated actually by finding the volume of the members and multiplying it by the density of the concrete. In STAAD-Pro it can easily be calculated by using the command self-weight with the factor -1

Earth Pressure:
Height of soil						=	6.900	m
The angle of internal friction						=	30.00	o
Coefficient of earth pressure at rest						=	0.500
Earth pressure intensity at the top						=	0	kN/m2
Earth pressure intensity at the bottom						=	69	kN/m2
Height of surcharge(due to LL)						=	1.20	m

AS PER IRC:6-2010
For 70R-Wheeled Boogie
Clear distance						=	1.07	m
Width of the track (transverse to traffic dir.)						=	0.81	m
Width of the track (along traffic dir.)							0.26	m
Total width of the vehicle						=	2.79	m
width center to center of wheel						=	1.98	m
For 70R - Tracked
Clear distance						=	1.20	m
Width of the track (transverse to traffic dir.)						=	0.84	m
Width of the track (along traffic dir.)							4.57	m
Total width of the vehicle						=	2.90	m
width center to center of wheel						=	2.06	m
For CL - Tracked
Clear distance						=	1.20	m
Width of the track (transverse to traffic dir.)						=	0.84	m
Width of the track (along traffic dir.)							4.57	m
Total width of the vehicle						=	2.90	m
width center to center of wheel						=	2.06	m
For CL-A wheeled
Clear distance						=	1.30	m
Width of the wheel (transverse to traffic dir.)						=	0.50	m
Width of the wheel (along traffic dir.)							0.25	m
Total width of the vehicle						=	2.30	m
width center to center of wheel						=	1.8	m
For Special Vehicle
Clear distance						=	0.60	m
Width of the wheel (transverse to traffic dir.)						=	0.16	m
Width of the wheel (along traffic dir.)							0.27	m
Total width of the vehicle						=	3.00	m
width center to center of wheel						=	1.8	m

For 70R-Wheeled Boggie
Impact factors
Impact factor =		24.19%
Effective Dispersion Width:
Dispersion of loads through fills and wearing coat (at 45° angle):
beff	=	b + 2 * (wc + D + s)
b	=	tyre width along traffic flow			=	0.263	m
wc	=	wearing coat			=	0	m
D	=	Overall depth of slab			=	0.600	m
s	=	thickness of soil above box			=	1.5	m
	Hence, dispersion width				=	4.463	m	Along the span
Calculation of effective width:
beff =	k * x (1 - x/lo) + b1
k =	constant depending on b/lo				=	2.233651	(for b/lo =	0.9921 )
lo =	effective span				=	12.60	m
x =	Distance of centre of gravity from nearest support				=	6.3	m (for max. moment case)
x =						0.61	m (for max. vertical load case)
b =	tyre width across traffic flow				=	0.81	m
wc =	wearing coat				=	0	m
b1 =	width of tyre + 2 x thickness of w.c.				=	3.81	m
	Hence, beff for max moment case				=	10.846	m	Perpendicular
	Hence, beff for max vertical load case				=	5.107	m	to the span
Max bending moment in span due to moving conc load will occur under conc load which is near to cg of load system
when the centre of span is midway between the cg of load system and the conc. load under consideration.
Maximum axial load in abutment will occur when c.g of heavy loads is near the WALL.

Pressure on top slab :

(i) Maximum moment case :

40 T load is dispersed with overlappings in both the directions
UDL due to live load					=	0.917	T/m2
longitudinal dispersion					=	5.683	m
transverse dispersion					=	8.603	m

(ii) Maximum vertical load on wall :

UDL due to live load					=	1.376	T/m2
Dispersion length of live load in longitudinal direction					=	2.842	m
transverse dispersion					=	5.73	m

For 70R - Tracked
Impact factors
Impact factor =		10.00%
Effective Dispersion Width
Dispersion of loads through fills and wearing coat (at 45° angle):
beff	=	b + 2 * (wc + D + s)
b	=	tyre width along traffic flow			=	4.57	m
wc	=	wearing coat			=	0	m
D	=	Overall depth of slab			=	0.600	m
s	=	thickness of soil above box			=	1.5	m
	Hence, dispersion width				=	8.77	m	Along the span
Calculation of effective width:
beff =	k * x (1 - x/lo) + b1
k =	constant depending on b/lo				=	2.234	(for b/lo =	0.99 )
lo =	effective span				=	12.60	m
x =	Distance of centre of gravity from nearest support				=	2.285	m
x =	Distance of centre of gravity from nearest support				=	1.1425	m
b =	tyre width along traffic flow				=	0.84	m
wc =	wearing coat				=	0	m
b1 =	width of tyre + 2 x thickness of w.c.				=	3.84	m
	Hence, beff for max moment case				=	8.018	m
	Hence, beff for max vertical load case				=	6.1605	m
Max bending moment in span due to moving udl will occur when udl occupies full span
Max bending moment in span due to moving conc load will occur under conc load which is near to cg of load system
when the centre of span is midway between the cg of load system and the conc. load under consideration.
Maximum axial load in abutment will occur when c.g of heavy loads is near the abutment.

Pressure on top slab :

(i) Maximum moment case :

UDL due to live load					=	1.153	T/m2
Dispersion length of live load in the longitudinal direction					=	8.77	m
transverse dispersion					=	7.27	m

(ii) Maximum vertical load on wall :

UDL due to live load =						1.738	T/m2
Dispersion length of live load in the longitudinal direction					=	6.67	m
transverse dispersion					=	6.34	m

For CL-A wheeled			3 Lanes of CL-A
Impact factors
Impact factor =		24.19%
Effective Dispersion Width
Dispersion of loads through fills and wearing coat (at 45° angle):
beff	=	b + 2 * (wc + D + s)
b	=	tyre width along traffic flow			=	0.25	m
wc	=	wearing coat			=	0	m
D	=	Overall depth of slab			=	0.600	m
s	=	thickness of soil above box			=	1.5	m
	Hence, dispersion width				=	4.45	m	Along the span
Calculation of effective width:
beff =	k * x (1 - x/lo) + b1
k =	constant depending on b/lo				=	2.234	(for b/lo =	0.99 )
lo =	effective span				=	12.60	m
x =	Distance of centre of gravity from nearest support				=	6.3	m
b =	tyre width along traffic flow				=	0.50	m
wc =	wearing coat				=	0	m
b1 =	width of tyre + 2 x thickness of w.c.				=	3.5	m
	Hence, beff for max moment case				=	10.536	m
Max bending moment in span due to Class A will occur when 11.4 T axle is placed near the mid span
Max bending moment in span due to moving conc load will occur under conc load which is
near to cg of load system when the centre of span is midway between the cg of load system
and the conc load under consideration

Pressure on top slab :

(i) Maximum moment case :

UDL due to live load					=	1.083	T/m2
Dispersion length of live load in the longitudinal direction					=	5.65	m
transverse dispersion					=	12.500	m

70R + Class A:
Impact factors
Impact factor =		24.19%
Effective Dispersion Width
Dispersion of loads through fills and wearing coat (at 45° angle):
beff	=	b + 2 * (wc + d + s)
b	=	tyre width along traffic flow			=	0.26	m
wc	=	wearing coat			=	0	m
D	=	Overall depth of slab			=	0.600	m
s	=	thickness of soil above box			=	1.5	m
	Hence, dispersion width				=	4.463	m	Along the span
Calculation of effective width:
beff =	k * x (1 - x/lo) + b1
k =	constant depending on b/lo				=	2.234	(for b/lo =	0.99 )
lo =	effective span				=	12.60	m
x =	Distance of centre of gravity from nearest support				=	6.3	m
b =	tyre width along traffic flow				=	0.81	m
wc =	wearing coat				=	0	m
b1 =	width of tyre + 2 x thickness of w.c.				=	0.81	m
	Hence, beff for max moment case				=	7.846	m
Max bending moment in span due to 70R vehicle will occur when 17T (with 1.37m spacing) will occupy the midspan
Max bending moment in span due to moving conc load will occur under conc load which is near to cg of load system
when the centre of span is midway between the cg of load system and the conc. load under consideration.

UDL due to live load					=	0.871	T/m2
Dispersion length of live load in the longitudinal direction					=	5.833	m
transverse dispersion					=	12.50	m

For Special Vehicle
Impact factors
Impact factor =		0.00%
Effective Dispersion Width
Dispersion of loads through fills and wearing coat (at 45° angle):
beff	=	b + 2 * (wc + d + s)
b	=	tyre width along traffic flow			=	0.274	m
wc	=	wearing coat			=	0	m
d	=	effective depth of slab			=	0.600	m
s	=	thickness of soil above box			=	1.5	m
	Hence, dispersion width				=	4.474	m	Along the span
Calculation of effective width:
beff =	k * x (1 - x/lo) + b1
k =	constant depending on b/lo				=	2.233651	(for b/lo =	0.992 )
lo =	effective span				=	12.60	m
x =	Distance of centre of gravity from nearest support				=	6.3	m (for max. moment case)
x =	Distance of centre of gravity from nearest support				=	0.75	m (for max. vertical load case)
b =	tyre width across traffic flow				=	0.156	m
wc =	wearing coat				=	0	m
b1 =	width of tyre + 2 x thickness of w.c.				=	3.156	m
	Hence, beff for max moment case				=	10.192	m	Perpendicular
	Hence, beff for max vertical load case				=	4.732	m	to the span
Max bending moment in span due to moving conc load will occur under conc load which is near to cg of load system
when the centre of span is midway between the cg of load system and the conc. load under consideration.
Maximum axial load in abutment will occur when c.g of heavy loads is near the WALL

Pressure on top slab :

(i) Maximum moment case :

40 T load is dispersed with overlappings in both the directions
UDL due to live load					=	0.744	T/m2
longitudinal dispersion					=	5.974	m
transverse dispersion					=	8.096	m

(ii) Maximum vertical load on wall :

UDL due to live load					=	1.123	T/m2
Dispersion length of live load in longitudinal direction					=	2.987	m
transverse dispersion					=	5.37	m

COMPUTATION OF FORCE DUE TO TEMPERATURE GRADIENT:

The variation of temperature gradient as follows:

Grade of Concrete = M30
"YOUNG'S MODULUS, E =" 3.10E+06 t/m2
"Coeff. Of Thermal Expansion,a =" 1.20E-05 / oC

Computation of Forces in Members due to Temperature Rise Case:

Node "1, 2 & 6, 7"
MEMBER 1 & 6
Thickness of member = 600 mm

STRESS
17.8 662.2 t/m2
F1 = 60.82 t
150 F1 e1 e1 = 0.059 m
4 148.8 t/m2 F2 = 13.39 t
e2 = 0.120 m
180 F2
e2
0 0.0 t/m2

Net force on member = 74.21 t
Net moment on member = 15.853 tm

Node 3 & 5
MEMBER 2 & 5
Thickness of member = 600 mm

STRESS
17.8 662.2 t/m2
F1 = 60.82 t
150 F1 e1 e1 = 0.0592 m
4 148.8 t/m2 F2 = 13.39 t
e2 = 0.1200 m
180 F2
e2
0 0.0 t/m2

Net force on member = 74.21 t
Net moment on member = 15.853 tm

Node 4
MEMBER 3 & 4
Thickness of member = 600 mm

STRESS
17.8 662.2 t/m2
F1 = 60.82 t
150 F1 e1 e1 = 0.0592 m
4 148.8 t/m2 F2 = 13.39 t
e2 = 0.1200 m
180 F2
e2
0 0.0 t/m2

Net force on member = 74.21 t
Net moment on member = 15.853 tm

Node "1, 2 & 6, 7"
MEMBER 1 & 6
Thickness of member = 600 mm

STRESS
0 0.0 t/m2
F1 = 5.86 t
150 F1 e1 = 0.0500 m
e1

2.1 78.1 t/m2

Net force on member = 5.86 t
Net moment on member = 1.465 tm

Node 3 & 5
MEMBER 2 & 5
Thickness of member = 600 mm

STRESS
0 0.0 t/m2
F1 = 5.86 t
150 F1 e1 = 0.0500 m
e1

2.1 78.1 t/m2

Net force on member = 5.86 t
Net moment on member = 1.465 tm

Node 4
MEMBER 3 & 4

Thickness of member = 600 mm

STRESS
0 0.0 t/m2
F1 = 5.86 t
150 F1 e1 = 0.0500 m
e1

2.1 78.1 t/m2

Net force on member = 5.86 t
Net moment on member = 1.465 tm

Computation of Forces in Members due to Temperature Fall Case:

Node "1, 2 & 6, 7"
MEMBER 1 & 6
Thickness of member = 600 mm

STRESS
10.6 394.3 t/m2
F1 = 25.22 t
120 F1 e1 e1 = 0.0425 m
0.7 26.0 t/m2 F2 = 1.95 t
e2 = 0.1000 m
150 F2
e2
0 0.0 t/m2

Net force on member = 27.17 t
Net moment on member = 6.749 tm

Node 3 & 5
MEMBER 2 & 5
Thickness of member = 600 mm

STRESS
10.6 394.3 t/m2
F1 = 25.22 t
120 F1 e1 e1 = 0.0425 m
0.7 26.0 t/m2 F2 = 1.95 t
e2 = 0.1000 m
150 F2
e2
0 0.0 t/m2

Net force on member = 27.17 t
Net moment on member = 6.749 tm

Node 4
MEMBER 3 & 4
Thickness of member = 600 mm

STRESS
10.6 394.3 t/m2
F1 = 25.22 t
120 F1 e1 e1 = 0.0425 m
0.7 26.0 t/m2 F2 = 1.95 t
e2 = 0.1000 m
150 F2
e2
0 0.0 t/m2

Net force on member = 27.17 t
Net moment on member = 6.749 tm

Node "1, 2 & 6, 7"
MEMBER 1 & 6

Thickness of member = 600 mm

STRESS
0 0.0 t/m2
e2
150 0.8 F2 29.8 t/m2
F1 = 16.52 t
120 F1 e1 = 0.0443 m
e1 F2 = 2.23 t
e2 = 0.1000 m
6.6 245.5 t/m2

Net force on member = 18.75 t
Net moment on member = 4.513 tm

Node 3 & 5
MEMBER 2 & 5
Thickness of member = 600 mm

STRESS
0 0.0 t/m2
e2
150 0.8 F2 29.8 t/m2
F1 = 16.52 t
120 F1 e1 = 0.0443 m
e1 F2 = 2.23 t
e2 = 0.1000 m
6.6 245.5 t/m2

Net force on member = 18.75 t
Net moment on member = 4.513 tm
Node 4
MEMBER 3 & 4

Thickness of member = 600 mm

STRESS
0 0.0 t/m2
e2
150 0.8 F2 29.8 t/m2
F1 = 16.52 t
120 F1 e1 = 0.0443 m
e1 F2 = 2.23 t
e2 = 0.1000 m
6.6 245.5 t/m2

Net force on member = 18.75 t
Net moment on member = 4.513 tm

Summary of Bending Moments and Shear Forces

ULS
BOTTOM SLAB (LOAD COMB 100 - 235)
TOP SLAB & WALLS (LOAD COMB 282 - 348)
Node.No	Element	Location	Bending moment (LHS)	Bending moment (RHS)	Shear Force (LHS)	Shear Force (RHS)
5	Bottom Slab	Support	477.242	315.378
6		deff			418.267	357.266
7		Curtailment	271.216	343.537	186.671	250.737
8		Midspan	427.459		224.817

SLS (LOAD COMB 236-271)
Node.No	Element	Location	Bending moment	Bending moment
5	Bottom Slab	Support	321.027	216.16
7		Curtailment	66.121	235.938
8		Midspan	302.26

QUASI (LOAD COMB 272-281)
Node.No	Element	Location	Bending moment	Bending moment
5	Bottom Slab	Support	197.619	197.612
7		Curtailment	52.363	133.874
8		Midspan	225.036

Check for Flexure

Design of Different Sections by ULS Method:

Concrete Grade =

M30

Steel Grade =

Fe500

fcd =

13.4

Clear cover to r/f =

45mm

For walls & Top slab

Allowable Crack Width =

0.3

mm

fywd =

348

75mm

Bottom slab

fctm =

2.5

Mpa

fyk=

500

Mpa

SL. NO	DESCRIPTION		Units	Bottom Slab
				Support	at Curtailment section	Midspan
1	Design Moments		tm	47.7	34.4	22.5
2	Design Shear Forces			41.8	25.1	0.0
2	Design Shear Forces		t	41.8	25.1	0.0
3	Overall width provided		mm	1000	1000	1000
4	Overall depth provided		mm	650	650	650
5	Check for Flexure
	Effective cover provided		mm	88	85	85
	Effective depth provided, d		mm	563	565	565
	MR from concrete =0.133*fck*b*d2		Nmm	1.26E+09	1.27E+09	1.27E+09
	Provided Ast for "+" BM		mm2	3460	1571	3142
	Minimum Reinforcement = 0.13%btd or 0.26*(fctm/fyk)*btd		mm2	731	735	735
	Status of Section			OK	OK	OK
	Lever arm, z =({1-0.974*fy*As/(fck*b*d)}		mm	506	540	514
	MR of steel =0.87*fy*As*z=		Nmm	7.62E+08	3.69E+08	7.02E+08
	Moment of Resistance of Section		tm	76.2	36.9	70.2
	Status of Section			OK	OK	OK
6	Provision of Reinforcement
				Bottom Slab
				Support		Midspan
	Provided Reinforcement		Spacing	200	200	200
			Dia	16	20	20
			Spacing	200	200	200
			Dia	25	0	20
			Spacing	0	0	0
			Dia	0	0	0
	Neutral axix Depth			84.18	59.20	74.50
	M/(bd2Fav) = kav			0.14	0.10	0.12
	Required reinforcement As			2075.65	1459.65	1836.99
	Distribution Reinforcement = 20% of Main Reinforcement to be provided on both faces		=20% of Ast	415	292	367
			Max reqd	415	292	367
			Provided	646	646	646
	Top face		Spacing	175	175	175
			Dia	12	12	12
	Bottom face		Spacing	175	175	175
			Dia	12	12	12
				OK	OK	OK

Check for Shear
			Support	at Curtailment section	Midspan
Ult. Applied Shear Force, Vult		KN	418	251	0
Overall Width, bw		m	1.000	1.000	1.000
Overall Depth, h		m	0.650	0.650	0.650
v =0.6[1-(fck/310)]			0.542	0.542	0.542
Max Shear Check VEd <=0.5bw d v fcd		KN	2042	2051	2051
			OK	OK	OK
Area of Section		m2	0.650	0.650	0.650
Horizontal Force		KN	167.9	0.0	0.0
Cg of steel		m	0.088	0.085	0.085
Comp. Stress due to Horizontal force, scp		Mpa	0.258	0.000	0.000
VRd.c =	[0.12K(80r1.fck)0.33+0.15scp]bw.d
Overall Width, bw		m	1.000	1.000	1.000
z = (D - Yord)		m	0.563	0.565	0.565
K = 1+ 200/d <= 2.0			1.60	1.59	1.59
r1			0.006	0.003	0.006
vmin = 0.031 K 3/2 fck 1/2		Mpa	0.342	0.342	0.342
VRd.c =		KN	284	202	254
vRd.c min =(vmin + 0.15scp)bw.d		KN	214	193	193
Govering VRdc=		KN	284	202	254
Design Shear Capacity, Vc		KN	284	202	254
Provision of Shear Reinforcement (Cl. 10.3.3.2 of IRC 112-2011)
Ultimate Applied Shear, Vuapplied		kN	418	251	0
av		mm	563	565	565
b	= av/2d		1	1	1
Vu		kN	418	251	0
Design Shear Capacity, Vc		kN	284	202	254
Reqirement of shear reinforcement			YES	YES	NO
acw			1.009	2.500	2.500
n1			0.600	0.600	0.600
Maximum allowable shear stess (q = 45)		Mpa	3.658	3.658	3.658
Allowable shear stress ( q = 21.8)		Mpa	2.52	2.52	2.520
actual Shear stress		Mpa	0.8262	0.4931	0.000
Since the actual shear stress is less than allowable shear stress with q of 21.8 degrees, q is limited to 21.8 degrees
i) Aswmax / S = 0.5*bw*acw*n1*fcd/(fywd)		mm2/m	11657.020	28893.750	28893.750
ii) 0.072 x (SQRT(fck))/fyk		mm2/m	788.720	788.720	788.720
Shear reinforcement required Asv/Sv = (Vu)/(z*fywd) cotq		mm2/m	1068.828	637.892	0.000
spacing of 5L-8mm S-links		mm	235.143	318.652	509.838
Spacing along the span of the box		mm	200.0	200.0	307.000

	Check for Stresses
Concrete Grade =		30.00					Steel Grade		=	Fe500
Clear cover to r/f =		45mm	For walls & Top slab				Elasticity modulus of Concrete		=	31000	Mpa
Clear cover to r/f =		75mm	Bottom slab
sst		=	300.000	Mpa
sck		=	14.40	Mpa
m		=	6.48

Bottom Slab

SL. NO	DESCRIPTION		Units
				at Curtailment section	Midspan
1	Design "+" Moments		tm	6.6	29.1
2	Overall width provided		mm	1000	1000
3	Overall depth provided		mm	650	650
4	Modulur ratio, m		mm	6.48	6.48
5	Check for Flexure
	Steel percentage (p)		mm	0.28	0.56
	Depth of neutral axis		mm	97	133
	Lever arm factor			530	521
	Effective cover provided		mm	85	85
	Effective depth provided, d		mm	563	565
	Provided Ast for "+" BM		mm2	1571	3142
	Stress in concrete		N/mm2	2.6	8.4
	Stress in reinforcement		N/mm2	79.4	177.9
	Status of Section			OK	OK

	Check for Crack width		Units	@ curtailment sections	Midspan
	Design Moments		tm	5.2	22.50
	Area of reinforcement		mm2	1571	3142
	Lever arm		mm	530	521
	Depth of Neutral Axis		mm	97	133
	Stress in concrete		N/mm2	2.0	6.5
	Stress in reinforcement		N/mm2	62.9	137.5
	Average Strain at the level, em			3.14E-04	6.88E-04
	Diameter check (As per cl.12.3.6 IRC:112-2011)			OK	OK
	Spacing check (As per cl.12.3.6 IRC:112-2011)			OK	OK
	Crackwidth at mid point between two bars
	Crackwidth Wk = Sr,max*(εsm - εcm)
	Provided spacing of tensile reinforcement		mm	100	100
	Φeq		mm	20	20
	hc,eff		mm	184	172
	ρp,eff			0.0085	0.0182
	Sr,max		mm	688	476
	kt			0.5	0.5
	fct,eff		Mpa	2.5	2.5
	αe			6.45	6.45
	Es		Mpa	2.00E+05	2.00E+05
	σsc		Mpa	62.9	137.5
	εsm - εcm = (σsc - (kt*fct,eff/ρp,eff)*(1+αe*ρp,eff))/Es			0.0002	0.0004
	Wk = Sr,max*(εsm - εcm)		mm	0.130	0.196
	Allowable crack width		mm	0.3	0.3
	Status of sections			OK	OK

Reinforcement Detailing:-