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For an open-deck steel plate girder railway bridge with rail joints, frequent damage to the bridge members and a high level of noise and vibration occur. By installing continuous welded rail (CWR) to the bridge, it is possible to reduce the noise and impact force of the bridge. However, current girder–sleeper fasteners have low lateral resistance in nature and track buckling can occur when CWR is used on such a bridge. Therefore, a new girder-sleeper fastener with proper lateral resistance to prevent CWR track buckling is needed. In this study, the lateral resistance requirements of a girder-sleeper fastener are investigated through a series of finite element (FE) analyses and parametric study. The effect of peak lateral resistance of the fastener, curve radius, girder length, and lateral displacement of girder are examined. From the analysis results, the peak lateral resistance criterion of the girder–sleeper fastener is proposed for the design of a new fastener for CWR tracks on an open-deck steel plate girder bridge.

For an open-deck steel plate girder railway bridge with rail joints, frequent damage to the bridge members and a high level of noise and vibration occur. By installing continuous welded rail (CWR) to the bridge, it is possible to reduce the noise and impact force of the bridge. However, current girder–sleeper fasteners have low lateral resistance in nature and track buckling can occur when CWR is used on such a bridge. Therefore, a new girder-sleeper fastener with proper lateral resistance to prevent CWR track buckling is needed. In this study, the lateral resistance requirements of a girder-sleeper fastener are investigated through a series of finite element (FE) analyses and parametric study. The effect of peak lateral resistance of the fastener, curve radius, girder length, and lateral displacement of girder are examined. From the analysis results, the peak lateral resistance criterion of the girder–sleeper fastener is proposed for the design of a new fastener for CWR tracks on an open-deck steel plate girder bridge. [ABSTRACT FROM AUTHOR]

China is prone to frequent earthquakes, impacting both the construction and operation of high-speed railways. The seismic response analysis is essential for the promotion and structural optimization of novel box-type subgrade structures. This paper develops a nonlinear integrated spatial dynamic model of a ballastless track and box-type subgrade, investigating structural vibrations under multi-dimensional seismic actions using the time–frequency domain method. A seismic performance analysis of the structure is conducted to examine the influence of seismic intensity on its seismic response. Results indicate that the box-type subgrades exhibit good integrity under seismic actions, primarily undergoing rigid body motion, with forces in all components well below design strength, meeting the Chinese seismic fortification requirements. Compared to traditional simply supported beams, box-type subgrades show better adaptability to earthquakes. As seismic intensity increases, vibrations and deformations of box-type subgrades change linearly, while vibrating forces increase nonlinearly. [ABSTRACT FROM AUTHOR]

Continuous welded rails on bridges are extensively employed in high-speed railways, where trains are predominantly electrically powered, and the open-air catenary represents the weakest link in the system. Despite the widespread use of continuous welded rail on bridges for high-speed railways, there exists a relative dearth of research on their vulnerability, particularly regarding seismic vulnerability studies that consider the catenary, track type, and bridge collectively. The vulnerability of fasteners and catenary on bridges under the longitudinal resistance of the line was investigated by constructing a 7−32 m high-speed railway double-line simply-supported box girder bridge. It reveals, for the first time, the influence of the longitudinal resistance of the line on the vulnerability of fasteners and catenary under seismic action. The study indicates that both the fasteners' and catenary's vulnerability increases with the intensity of ground shaking, with the catenary being more susceptible. The longitudinal resistance of the line has a greater impact on the fasteners' vulnerability than the catenary. When the degree of damage is minimal, the order of damage to the fasteners is the ballasted track, small resistance fastener, and ballastless track when the probability of exceedance is 5%. The ballastless track can significantly increase the probability of no damage to the fasteners, and it is recommended that the ballastless track be used when designing high-speed railway bridges in earthquake-prone regions. [ABSTRACT FROM AUTHOR]

Timber elements, such as timber bridges, are exposed to heavy loads. Therefore, reinforcement might be useful. Due to a lack of wood supplies, poplar, a fast-growing tree, could be used to construct CLT (cross-laminated timber). The low density of fast-growing wood species directly impacts the mechanical properties of CLT. Therefore, in this study, a CLT panel was reinforced with GFRP (glass-fiber-reinforced polymer), and the lateral resistance of double shear lap joints in reinforced CLTs with 0-90-0° arrangements in two strength directions was investigated. Lag screws (Ø = 8 mm) at the end distances of 1 and 3 cm were employed for making the lateral test specimens. First, the effect of the number of GFRP layers on lateral resistance of the joints was investigated. The results revealed that, as the number of GFRP layers changed from one to three, the lateral resistance increased by 45.47%, and then, by four layers, it decreased by 1.3%. Since the joints with three layers of FRP had the highest strength, the effects of the end distance and the CLT panel strength directions on the lateral performance of the reinforced and non-reinforced specimens were investigated. The results indicated that the lateral resistance of reinforced CLTs with GFRP was about 26.5% more than the unreinforced ones. Moreover, CLTs in the major strength direction showed 4.2% more lateral resistance than those in the minor strength direction. Moreover, lag screws at the end distance of 3 cm had 60% more lateral resistance than those at the end distance of 1 cm. In terms of failure modes, bearing, shear, and net-tension modes were observed in the CLTs, while Is, IIIs, and IV modes were observed in the lag screws. [ABSTRACT FROM AUTHOR]

In the research proposed by Zeng et al. [[4]], the long-span steel truss slab track was used to analyze a new type of sleeper slab track structure with an experimental method. In order to study the mechanical properties and long-term performance of the new type of sleeper slab track structure, this paper carried out a full-scale indoor modal loading test of the concrete sleeper slab track structure to provide a reference for the engineering application. This paper carried out research on the dynamic effects of LVT heavy-haul railway wheels and rails and provided a technical reference for the structural design of heavy-haul railway track structures. The European Commission is developing a Single European Transport Area and has promoted a modal shift from road to rail to achieve a more competitive and resource-efficient transport system. [Extracted from the article]