The document discusses energy harvesting from vibration of railroad bridges using piezoelectric materials. Finite element models were created to simulate different trains passing over a bridge and calculate the power output of piezoelectric energy harvesters attached to the bridge. Experimental data on a real bridge was also analyzed. The modeling and experiments showed that lead zirconate titanate (PZT) generated more power than polyvinylidene fluoride (PVDF) but is more brittle. Train-induced vibrations were found to provide enough power for wireless sensors. Damage detection was also explored by modeling and measuring changes in the harvested energy from localized damage.

1. 4/01/
2022
Mahesh Pokhrel
UTRGV
(Paul Cahill et al,
2014)
ENERGY HARVESTING FROM TRAIN-INDUCED
RESPONSE IN BRIDGES

2. INTRODUCTION
 Among different piezoelectric materials (ceramics, polymers),
identification of the most suitable material for specific applications.
 Lots of attention on energy harvesting from vibration of bridges
and potential use.
Piezoelectric Materials:
 PZT (Lead zirconate titanate) - most used due to excellent
piezoelectric properties. But is brittle (ceramic).
 PVDF (Polyvinylidene fluoride) – high mechanical strength
and flexible (polymer). Lower piezoelectric properties
Piezoelectric Energy-Harvesting System:
 An adhesive patch system is evaluated for energy harvesting which do not
require to tune with natural resonant frequency of the structure.
 Can be achieved directly from the variation in the strain conditions.
Ref: Zhengbao Yang et al, 2018

3.  Investigate the energy harvesting from the vibration
of railroad bridge and potential application.
OBJECTIVES
 Plot the Consistent and monotonic damage calibration curves.
 Compare dynamic response against experimental analysis.

4. Modeling
Energy
harvester
Attach externally to the
underside surface of model
Perfect connection for
identical strain conditions
Piezoelectric principle for coupled
electromechanical behavior
Strain profile at the location
and voltage calculation
Energy storage and power-handling
circuit to provide power to the sensors
METHODOLOGY

5. Train Number of
carriages
Total
Load (KN)
071Loco 7 4266.8
201Loco 7 4390.6
TGV 10 4748
ICE 12 8240
Shinkansen 14 6867
Train-Bridge
Modeling
Ireland
Ireland
France
Germany
Japan

6. Train-Bridge Modeling
3D FE model in Strand7 software, dimensions of 10.6 m x 10 m with 2 tracks, speed 40-
160km/hr
Single and double trains were passed and harvesting system located at
midspan.
A differential equation (DE) was created to compare with FE model and ultimately the
strain was used to calculate the energy output.
Fig: Strain output for FE and DE models for 201Loco (100 km/h)
 Found good correlation for each
train
 Responses from FE model were
larger (avg 30%) than DE models
1
2
3
(Strand7)

7. Single-Train Passage
Power Output Results
Fig: Energy-harvesting system power outputs for single and double -train
passages
Double train passage
201Loco-382 - 397 µW (FE) and 223 - 363 µW (DE).
Requirement - 100 µW.
ICE train- 588 µW (PZT) and 307.1 µW (PVDF)
Power
34–52%.
(Ref: Wahied G. Ali, Sutrisno W. Ibrahim, 2012)

8. Energy Harvesting (Experimental Data)
 Single-span steel–concrete composite bridge with single
ballasted track, 36m x 6.7m (Lorieux 2008).
Fig: Skidträsk Bridge at Northern Sweden
 First case - a single-locomotive passing at 60 to 180 km/h.
 Second case - a loaded freight train (Steel Arrow) two
locomotives and 26 wagons.
Fig: Experimental and model strain profiles of Steel Arrow (65
km/hr)
 A 2D beam model was created with
five different cross sections
representing the variation.
 The experimental data, FE,
and DE model all correlated
well.

9. Locomotive Passages:
RESULTS
 For single passage, PZT produced 1.55 µW at
118 km/h (experimental) and 1.31 µW (model).
 At same speed, the PVDF produced 0.83 µW
from experimental and 0.7 µW from the model.
Steel Arrow freight train Passages:
PZT produced 24.1 - 16.9 µW from experimental
and 23.4 - 16.1 µW from models.
PVDF produced 12.8 - 12.4 µW from
experimental and 9 - 8.6 µW from the models.
higher than single locomotive.

10. The calibration depends on; power generated at the undamaged bridge, storage capacity, required power,
number of train passages for a given time period.
For SHM, the power ∝ RMS voltage (over the time but not dependent on individual measurements)
 Any damage to the bridge result in a change in the pattern of energy harvested.
Indicate Presence and position, not the type of damage.
Structural Health-Monitoring Potential

11. Modeling of Damage:
Fig: Modeling of localized
damage
 The 201Loco train at 100 km/h.
 Damage modeled at two locations, with
varying crack depth ratio (CDR) 0.05 to
0.20 and two widths 0.4m and 0.8m.
Damage Detection:
 The region closest to the damage experienced the
largest variation and significant for larger width
compared to undamaged model.
 Found increased change in the normalized power
closer to damage.
 Significant increase in the magnitude of the power
with increasing CDR at the position of damage.

12. Fig: Quarter-span Damage
Responses
Fig: Mid-span Damage Responses
Responses at the damage location:

13. Fig: Normalized power harvesting
from experimental analysis of
damaged beam
 The vehicle accelerated, strain data analyzed,
and the power harvested for varying CDR.
 Two-axle vehicle, with an axle distance of 0.11 m, traversing
a phenolic beam of length 0.91 m. Open crack located along
the lower section, with CDR of 0.167, 0.33, and 0.5. (Pakrashi
et al 2010)
Structural Health-Monitoring (Experimental)

14. CONCLUSIONS:
 Piezoelectric harvesting systems are found appropriate to power
wireless sensors (as determined with FE and DE models)
 PZT produced high power than PVDF but has a brittle nature.
 Different trains harvested different magnitude of energy. Max
power 588 µW from ICE train, and 24.1 µW from freight train
(Steel Arrow), both from PZT.
 Bridges with high dynamic responses are more suitable for
SHM. An array of harvesting systems can determine damage as
verified by laboratory data.

15. REFERENCE
 Paul Cahill et al 2014, “Energy Harvesting from Train-Induced Response in Bridges”
10.1061/(ASCE)BE.1943-5592.0000608. © 2014 American Society of Civil Engineers.
 ZhengbaoYang et al 2018, “High-Performance Piezoelectric Energy Harvesters and Their
Applications” https://doi.org/10.1016/j.joule.2018.03.011