Ultimate Load Prediction in Composite I-Beams

clanmurderUrban and Civil

Nov 15, 2013 (3 years and 6 months ago)

82 views

Ultimate Load Prediction in Composite I
-
Beams


Eric v. K. Hill and Edward C.
Fatzinger

APPROACH/TECHNICAL CHALLENGES


Ten fiberglass/epoxy beams cantilever loaded at
333
lb
f
/min using MTS hydraulic actuator


Record AE data during loading to failure from web
mounted transducer next to fixed support


Train BPNN on
low proof load (≤25% of average
ultimate load)

AE amplitude histograms from 6
beams (1, 3, 4, 6, 7 and 8) as inputs; then test
(predict) ultimate loads on remaining 4 beams (2,
9, 10 and 11)

ACCOMPLISHMENTS/RESULTS


Worst case prediction error:
12.9%

OBJECTIVES


Back
-
propagation neural network (BPNN)
prediction of ultimate load in composite I
-
beams
using low proof load acoustic emission (AE)
amplitude distribution (histogram) data as input


Goal:

Worst case prediction error within
±
15%

Composite I
-
Beam under Cantilever Load

with AE Transducers Attached

Piezoelectric

Element

Wear Plate

Integral

Preamplifier

BNC

Connector

Physical Acoustics Corporation

R
-
15I AE (150 kHz Resonant)
Transducer with Integral Preamplifier

47”

14”

10”

2”

0.375” Radius

2.5”

1.4”

0.2”

0.2”

Fillet Radius 0.2”

Composite I
-
Beam Construction

Exploded View

End View

Side View

NeuralWorks

Professional II/PLUS
®
Software

Predicted
Ultimate Load

570
lb
f

Worst Case
Error: 12.9%

Actual

Ultimate Load

505
lb
f

Beam #
Load (lbf)
Predicted (lbf)
% Error
1
1160
1122
-3.3
2
916
1012
10.5
3
944
946
0.2
4
975
897
-8
6
996
979
-1.7
7
472
485
2.8
8
1180
1171
-0.8
9
338
365
8
10
505
570
12.9
11
472
502
6.4
BPNN for Predicting
Composite I
-
Beam
Ultimate Load from
Low Proof Load AE
Amplitude Data

Comp10 (Amplitude distribution)
0
50
100
150
200
250
300
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
Amplitude (dB)
Frequency
Failed Composite I
-
Beam


and AE Analyzer

BPNN Training and Test Results

AE Amplitude Parameter

Amplitude Histogram

(≤25% Average S
u
)