Research Article

Damage Detection in Bridge Structures through Compressed Sensing of Crowdsourced Smartphone Data

Algorithm 2

Numerical investigation procedure.
Input: Acceleration signals for the baseline and an unknown case
Output: Damage index for the unknown case
Data Compression: Acquire and compress the acceleration signals of vehicles passing over the bridge, considering a specified compression level for both cases.
Reconstruction of Original Signals: Reconstruct all original signals using the CS theory.
for each run (Run number 30) do
Signal Selection: Randomly select 50% of the baseline signals as a baseline set. Use the remaining signals as a validation set. Similarly, select only 50% of the recorded signals for the unknown case.
Feature Extraction: Extract feature matrices using MFCC analysis from the selected signals in both cases separately.
PCA: Apply PCA to reduce dimensionality and obtain principal components of the feature matrices separately.
Probability Distribution Functions: Calculate the multivariate probability distribution of the projected features for both cases.
Dissimilarity Measure between the PDFs: Calculate the Wasserstein distance between the probability distribution of the baseline and the unknown case.
end
Average Wasserstein distance: Calculate the average Wasserstein distance over the 30 runs.
Damage Index: Normalize the average Wasserstein distance value with respect to the average from the validation set.
Output: Output the normalized damage index for the unknown case.