Comparison of Area method and Critical live load
reaction
Most users will compare EsteemPlus reaction by area method, while EsteemPlus is using elastic
method to obtain the reaction hence the result is not consistent to the user one. To explain this
more clearly let’s us compare using project as follow.
Comparison 1 (2 span)
Case 1
Total DL udl
=
0.3*0.5*24
=
3.6kN/m
Area method
R1
The DL reaction
=
3.6*2
=
7.2kN
The LL reaction
=
10*2
=
20kN
R2
The DL reaction
=
3.6*4
=
14.4kN
The LL reaction
=
10*4
=
40kN
Total unfactor loading =
R1+R2+R1
=
7.2+20+14.4+40+7.2+20
=
108.8kN
4000
4000
10kN/m run Live load
R1
R1
R2
300x300
x3000
ht.
column
300x500RC
Beam
Critical live load reaction off (from Esteem calculation)
Click here
Untick
here
Design Beam
Beam detailing
generated
BM and SF
diagram
generated
10kN/m LL
3.6kN/m LL
Hence sum of all reaction
=
5.4+18+5.4+15+50+15
=
108.8
It’s benchmarked with Area method
Summary of all
reaction
Critical live load reaction on (from Esteem calculation)
Hence sum of all reaction
=
5.4+18+5.4+17.5+50+17.5
=
113.8
It different with Area method about
=
[(113.8-108.8)/108.8]*100
≈
4.6%
Summary of all
reaction
Comparison 2 (3 span)
Total DL udl
=
0.3*0.5*24
=
3.6kN/m
Area method
R1
The DL reaction
=
3.6*2
=
7.2kN
The LL reaction
=
10*2
=
20kN
R2
The DL reaction
=
3.6*4
=
14.4kN
The LL reaction
=
10*4
=
40kN
Total unfactor loading =
R1+R2+R2+R1
=
7.2+20+14.4+40+14.4+40+7.2+20
=
163.2kN
4000
4000
10kN/m run Live load
R1
R2
R2
300x300x
3000 ht.
column
300x500RC
Beam
4000
R1
Critical live load reaction off (from Esteem calculation)
Hence sum of all reaction
=
5.8+15.9+15.9+5.8+16+44+44+16
=
163.4kN
It’s benchmarked with Area method
Summary of all
reaction
Critical live load reaction on (from Esteem calculation)
Hence sum of all reaction
=
5.8+15.9+15.9+5.8+18+48+48+18
=
175.4kN
It different with Area method about
=
[(175.4-163.2)/163.2]*100
≈
7.5%
Summary of all
reaction
Comparison summary (1span) between reaction
The benchmarking result is tabulated as