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The Bogeda Shan (Mountain) is in southern part of the Central Asian Orogenic Belt (CAOB) and well preserved Paleozoic stratigraphy, making it an ideal region to study the tectonic evolution of the CAOB. However, there is a long-standing debate on the tectonic setting and onset uplift of the Bogeda Shan. In this study, we report detrital zircon U-Pb geochronology and whole-rock geochemistry of the Permian sandstone samples, to decipher the provenance and tectonic evolution of the West Bogeda Shan. The Lower-Middle Permian sandstone is characterized by a dominant zircon peak age at 300–400 Ma, similar to the Carboniferous samples, suggesting their provenance inheritance and from North Tian Shan (NTS) and Yili-Central Tian Shan (YCTS). While the zircon record of the Upper Permian sandstone is characterized by two major age peaks at ca. 335 Ma and ca. 455 Ma, indicating the change of provenance after the Middle Permian and indicating the uplift of Bogeda Shan. The initial uplift of Bogeda Shan was also demonstrated by structural deformations and unconformity occurring at the end of Middle Permian. The bulk elemental geochemistry of sedimentary rocks in the West Bogeda Shan suggests the Lower-Middle Permian is mostly greywacke with mafic source dominance, and tectonic setting changed from the continental rift in the Early Permian to post rift in the Middle Permian. The Upper Permian mainly consists of litharenite and sublitharenite with mafic-intermediate provenances formed in continental island arcs. The combined evidences suggest the initial uplift of the Bogeda Shan occurred in the Late Permian, and three stages of mountain building include the continental rift, post-rift extensional depression, and continental arc from the Early, Middle, to Late Permian, respectively.

FRP rubber bearing was developed just almost 10 years ago, and it is characterized by less weight, lower cost, and better damping capacity. In this paper, the concept of the FRP rubber bearing is introduced first, and a finite element simulation of the bearing is presented then. At last the effects of dimension parameters on the compression performance of FRP rubber bearing are investigated, including the tensile stresses of the FRP plates and the vertical stiffness of the bearing. The influence laws of the dimension parameters are preliminarily concluded, and which can be taken as a reference for the design of FRP rubber bearings.

For continuous girder bridges, each bearing has different function requirements under normal traffic conditions and under earthquakes of different intensity levels. To meet the requirements of the three-level seismic design for continuous girder bridges presented in this paper, a new kind of multi-defense seismic spherical bearing is developed and its configuration and working mechanism are introduced in this paper. Then the results of mechanical properties test of the bearing are presented and it’s shown that the design requirements are all satisfied and the seismic performance of the bearing is effective and reliable.