Based on linear elastic theory, the concrete cracking problem of link slab on simply supported beam bridge was explored and theoretical analysis of bridge link slabs were carried out. Meanwhile, the formulas for calculating the stress of link slab were deduced and the cause for continuous damage of bridge deck was quantitatively analyzed. On the base of analysis of its failure mechanism, a new type of steel-concrete composite flat link slab was proposed. The results of full-scale model tests and finite element (FE) analysis indicated that it can alter the transfer path of internal forced inside the link slab and then concrete cracking can be prevented effectively. It was found that the main factors to link slab failure were influentially descending from girder end upturning, longitudinal tensile action and girder end rotation. Furthermore, the unbonded region between girder and link slab can effectively decrease the continuous stress and then alleviate the damage to bridge deck. All those results in this paper can be used as a reference and guidance for further research and development of new type of bridge link slab and jointless bridge.

In 2009–2022, to meet the requirement of resilient bridge pier structure (e.g., earthquake resistance, energy dissipation, isolation, resilience) for rapid repair after earthquakes and to improve the suitability of precast segmental bridge piers in medium- and high-intensity areas, a segmental assembled CFST bridge pier with external replaceable energy dissipator was proposed. Based on ABAQUS finite element analysis software, the finite element model of the CFST pier is established to analyze the force of the external replaceable energy dissipator, and the feasibility of the external energy dissipator is verified. Thereafter, two groups of segmentally assembled CFST pier model structures were tested for seismic behavior under reciprocating loading. Non-linear mechanical behaviors, such as restoring force-displacement hysteresis, loss of prestressing, and opening of the indirect joint of a segmented precast assembled pier, are analyzed. The results show that compared with a CFST pier with an energy dissipator, the lateral bearing capacity of the CFST pier with an external energy dissipator is increased by 32.8%, the energy dissipation capacity is also significantly improved, the opening size of joints between segments is reduced, and the overall damage of the CFST pier is concentrated on the energy dissipator, which is convenient for rapid disassembly and replacement. At the same time, the seismic performance of the CFST pier after replacing the energy dissipator is analyzed. The results show that the replacement of the external energy dissipator will not affect the seismic performance of a segmental assembled pier.

Ultrafast laser irradiation of single gold nanorods of various sizes is simulated for the investigation of the vibrations of the nanorods. The investigation uses a hybrid method that couples molecular dynamics (MD) with the two-temperature model (TTM). The extensional frequencies of the single gold nanorods are extracted from the atomic trajectories obtained by the MD simulations. In combination with continuum elasticity, the elastic moduli of the single gold nanorods are determined, along with the predicted extensional frequencies of the nanorods. It is shown that as the nanorod width increases, the modulus of the single gold nanorods also increases and approaches that of bulk gold. The notable softening of the elastic modulus is clearly shown for the smaller nanorods with widths of $\sim 8$ and $\sim 12\mathrm{nm}$.

Water leakage and debris accumulation caused by the expansion joints in a bridge superstructure reduce the service life of the bridge and increase the maintenance costs. A link slab is an effective means to eliminate the expansion joints, providing a continuous deck system. However, the load-caused concrete cracking of the link slab also leads to problems associated with water leakage and rebar corrosion. In order to solve these problems, a new type of steel–concrete composite link slab (SCC-LS) was designed to continuously subject the bridge deck to a positive bending moment and surface concrete compression, which reduced the cracking damage in the link slab. This paper presents the mechanical performance results of the SCC-LS obtained using full-scale model tests. Furthermore, theoretical calculations and finite element (FE) models of the jointless bridge validated the performance based on the experimental results. The results of this study show that the SCC-LS can effectively solve the problem of concrete cracking on the surface of the bridge deck, which has theoretical reference significance and engineering application value for the structural design, maintenance and transformation of continuous simply supported bridge decks and the promotion of seamless bridges.