Bridge Surface Roughness Identified from the Displacement Influence Lines of the Contact Points by Two Connected Vehicles

Abstract

In this study, a new, effective procedure is proposed for identifying the surface roughness from the responses recorded of two connected test vehicles moving over the bridge. Central to this study is the proposal of a simple static correlation formula for relating the dynamic deflections of the two vehicles’s contact points on the bridge, via the displacement influence lines (DILs). With the aid of this relation, the roughness formula for estimating the bridge surface profile is derived using the responses of the leading and following vehicles. It does not require any prior knowledge of the dynamic properties of the bridge. The efficacy of the proposed procedure is validated for both the simple and three-span continuous beams by the finite element method (FEM). Also, a parametric study is conducted for various physical properties of the test vehicles. It is confirmed that the roughness profiles back-calculated from the proposed formula agree excellently with the assumed ones for both the simple and continuous beams. For use in practice, the two connected test vehicles should not be designed too heavy and not to move at too fast speeds, in order to reduce the impact on the bridge.

Dynamic responses of a train-track-bridge coupled system under earthquakes

“…As reference in Fig. 3, eleven-span prestressed HSR two-way simply supported box-girder with concrete piers (bridge) and CRTS type II slab ballastless track are adopted in this paper, which is modelled based on the FEM [10,35]. The bridge and slab ballastless track are modelled based on the FEM [14].…”

Using vehicle–bridge contact spectra and residue to scan bridge's modal properties with vehicle frequencies and road roughness eliminated

“…[12][13][14][15][16][17] Furthermore, the vehicle scanning technique has been extended to the extraction of other bridge properties, such as mode shapes, [18][19][20][21][22][23][24][25] damping ratios, 26,27 damages, [28][29][30][31][32] and road surface roughness. [33][34][35] Some up-to-date reviews on applications of the VSM to highway bridges and/or railway tracks are available in Zhu and Law 36 and Yang et al 37 Previously, most researches used the vehicle response, that is, the response recorded by sensors installed on the vehicle's body, to identify the bridge modal properties and damages. Such a response suffers from the fact that the vehicle frequency itself may appear as a dominant frequency in the spectrum, thereby hindering the extraction of other bridge frequencies, 12,13,38 which gets worse in the presence of road pavement roughness.…”

“…Previously, the single-axle test vehicle has been used mostly by Yang and coworkers 12,13,15,17,18,35,39,42,43,47 for the fact that the physical model matches well the theoretical single-DOF model, which makes it easy to interpret the physical parameters involved. Such a single-axle test vehicle has been successfully adopted in various field tests.…”

“…As a first attempt, the dynamic response of a moving test vehicle was used to scan the bridge frequencies of simply supported bridges both theoretically and experimentally 12–17 . Furthermore, the vehicle scanning technique has been extended to the extraction of other bridge properties, such as mode shapes, 18–25 damping ratios, 26,27 damages, 28–32 and road surface roughness 33–35 . Some up‐to‐date reviews on applications of the VSM to highway bridges and/or railway tracks are available in Zhu and Law 36 and Yang et al 37 …”