Integral bridges are constructed without expansion joints, leading to a complete transfer of longitudinal deformations from the bridge deck to the substructure. While previous studies have predominantly addressed thermally induced loads, the effects of post-construction shortening in concrete decks due to shrinkage remain insufficiently explored. This study employs a validated numerical approach to parametrically investigate the combined influence of concrete shrinkage and thermal variations on the approach backfill. The results indicate that shrinkage induces notable settlements at the approach, compounding the long-term deformations already caused by cyclic ambient temperature fluctuations.