Section bearing capacity
Objective: Section bearing capacity
Task: Calculate ultimate moment strength of the section
References: Bliharsky Z.Y. Calculation and construction of bending reinforced concrete elements: Educational Guide / Z.Y. Bliharsky, I.I. Karhut. – Lviv: Lviv Polytechnic Publisher, 2017. – 188 p. (Example 5.10, pp. 73-75)
Initial data file:
ARBAT program section – Check, mode – Strength of RC Sections
Example-5.10-DBN.SAV
report – Arbat 5.10-DBN.doc.
Compliance with the codes: DBN V 2.6-98:2009, DSTU B.V 2.6-156:2010
Initial data:
b×h = 300×900 mm |
Beam section sizes |
а1= 27,5 mm |
Distance from the edge of the lower reinforcement to the lower edge of the cross-section (protective layer) |
А2= 20 mm |
Distance from the edge of the upper reinforcement to the upper edge of the section (protective layer) |
As1 = 2945 mm2 (6Ø25) |
Area of the lower reinforcement Cross-sectional area of reinforcement |
As2 = 942 mm2 (3Ø20) |
Area of the u reinforcement |
М= 810,7 kNm |
Bending moment |
Concrete class |
С20/25 |
Initial data in ARBAT:
Importance factor γn = 1
Effective length factor in the XoY plane 1
Effective length factor in the XoZ plane 1
Random eccentricity along Z according to DBN B.2.6-98:2009 with modification No.1
Random eccentricity along Y according to DBN B.2.6-98:2009 with modification No.1
The structure is statically determinate
Section
b = 300 mm h = 900 ммmm a1 = 27,5 mm a2 = 20 mm
|
S1 - 3Ø25, second line 3Ø25 (Clear distance between rows 35 mm) S2 - 3Ø20 |
---|
Reinforcement |
Class |
Additional service factor |
---|---|---|
Longitudinal |
A400C |
1 |
Transverse |
A240C |
1 |
Concrete
Concrete type: Heavy-weight
Concrete class: C20/25
Aggregate: Quartzite
Additional parameters |
|||
---|---|---|---|
Additional service factor |
1 |
|
|
Age of concrete (days) |
28 |
|
|
Cement strength class |
Class R |
|
|
Creep development time |
36500 |
days |
|
Temperature T(Δt) |
20 |
°C |
|
Number of days when the temperature T prevails Δt |
28 |
days |
|
Relative humidity |
40 |
% |
|
Results of analysis by load case combinations
|
N |
My |
Qz |
Mz |
Qy |
T |
Factor for sustained load |
Short-term |
Seismicity |
Special |
---|---|---|---|---|---|---|---|---|---|---|
kN |
kN*m |
kN |
kN*m |
kN |
kN*m |
|||||
1 |
0 |
810,7 |
0 |
0 |
0 |
0 |
1 |
|
|
|
Checked according to DBN |
Check |
Utilization Factor |
---|---|---|
|
Ultimate moment strength of the section |
0,991 |
Comparison of solutions
Check |
Ultimate moment strength of the section |
Guide |
810,7 kNm |
ARBAT |
810,7/0,991 = 818,1 kNm |
Deviation, % |
0,9 % |