Hybrid Common Femoral Vein Endophlebectomy and Iliac Vein Stenting Versus Femoro-Femoral Venous Bypass for Management of Chronic Iliofemoral Venous Occlusion

Elshazli, Mohamed

doi:10.1177/15266028261428269

Investigation on the instability mechanism and control strategies of ballasted track at the ends of long-span suspension bridges under longitudinal displacement

2026-06-18

0

PRE

AI

M

Min Xue

K

Kai Liu

T

Tianqi Pang

T

Tao Lü *

J

Junfeng Li

R

Rong Chen *

P

Ping Wang

DOI：10.1016/j.istruc.2026.112400

Original

Original request for help

Save

Abstract

En 中文

Ballasted tracks at the ends of long-span suspension bridges are subjected to complex cyclic longitudinal displacements and train dynamic loads, which may lead to severe ballast degradation and threaten track stability. To investigate the underlying instability mechanism and evaluate potential mitigation measures, this study develops a multiscale numerical framework by coupling a full-bridge finite element model with a local bridge-end ballast bed model based on the discrete element method and finite difference method. Using this framework, the ballast-bed responses under thermal loading and train loading are compared in terms of particle migration, geometric evolution, and mechanical performance degradation. Two distinct instability mechanisms emerge: thermal loading induces vertical dilatancy dominated by interfacial friction, while train loading triggers intense longitudinal ballast flow due to inertial effects. Quantitative analysis shows that train loading leads to degradation rates of 26.25% (longitudinal resistance) and 24.42% (sleeper support stiffness), both higher than the thermal loading values of 19.26% and 19.84%, respectively. To address this performance deterioration, two mitigation measures, sleeper densification and polyurethane stabilization, are evaluated. Results demonstrate that the latter forms an elastic bonding matrix that limits resistance degradation to 16.11%, markedly outperforming the former. The proposed multiscale approach provides an effective tool for analyzing continuum–granular interaction in bridge-track systems under complex boundary conditions and offers theoretical support for the design and maintenance of stable ballasted tracks at the ends of long-span bridges.

Investigation on the instability mechanism and control strategies of ballasted track at the ends of long-span suspension bridges under longitudinal displacement

Abstract

Journal

Organization

Cited Papers

Citing Papers