An experimental study and theoretical calculations of the flexural behaviour of segmental prestressed composite beams with corrugated steel webs are presented. Four specimens (one monolithic and three segmental beams) are tested. Based on the experiments, the flexural strength of the segmental beams is found to be approximately 0·75 of that of the monolithic beam, and the joint types of CSWs are found to have a little effect on the load-bearing capacity of the segmental beams. Moreover, the load-bearing capacity of the segmental beams is found to maximise by increasing the ratio of internal tendons in the bottom concrete flange to external tendons. Specifically, by increasing the ratio from 2:0:4 to 2:2:2, a 31% increase in the load-bearing capacity has been gained. Additionally, it has been found that the quasi-plane assumption is valid for the segmental beams with CSWs within the elastic range. Finally, a theory-based method for calculating the flexural bearing moment of segmental beams with CSWs is presented by considering the effect of the stress increment of the prestressed tendons.

<p>Lingdingyang Bridge of Shenzhong Link is a three-span suspension bridge with a full floating system of 580 + 1666 + 580. In view of the complex construction conditions of the bridge site, the construction scheme of island cofferdam was proposed for the east anchorage, and the flexible combined island cofferdam structure of ' lock steel pipe pile + I-shaped sheet pile + parallel steel wire rope ' was innovatively adopted to transform the offshore construction into land construction. For the east cable tower, the flexible manufacturing production line of steel mesh was developed, and the integrated intelligent tower building equipment suitable for ultra-high concrete cable tower was developed, forming the industrial construction technology of ultra-high cable tower based on reinforced bar product and intelligent tower building. The key construction technology of anchorage and tower solves the construction problem of super long-span suspension bridge in offshore sea, and improves the intelligent and industrial construction level of ultra-high tower engineering.</p>

<p>Precast segmental bridge with corrugated steel webs has good popularization value, for the ad- vantages of precast segmental construction and box girder with corrugated steel webs. In order to study the mechanical behavior of this structure,6 simply-supported scale model beams with cor- rugated steel webs were tested with the forming process, ratio of internal tendons to external tendons, shear-span ratio, number of joint, connection type of corrugated steel web,etc.,as the parameters. Stress variations in the concrete, web and tendon and deflection during loading are described, the crack generation and failure mode are also explained, the effects of parameters on the mechanical behavior of beams are analyzed. The study indicates that segmental beams have equal stiffness with monolithic beam in elastic stage, the joint affects the failure mode and causes decrease in the flexural bearing capacity, segmental beams with mixed post-tensioning or flange connector show better mechanical behavior than other segmental beams.</p>

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This article develops an enhanced UHPC-grout shear connection for steel-concrete composite bridges with precast decks. The primary improvement is the use of ultra-high performance concrete (UHPC) as the connection grout. To validate the constructability and the mechanical performance of the new connection, two series of experimental tests (including grouting tests and push-out tests) were conducted. Results from the grouting tests show that both the pressure grouting method and the self-levelling grouting method are applicable to inject the UHPC grout into the channel void of the connection. Results from the push-out tests indicate that the advanced properties of UHPC allow for a significant improvement of the shear resistance of the adhesive connection over traditional cementitious grouts. The ultimate shear capacity of the adhesive connection is controlled by the interface shear strength between the embossed steel and the UHPC grout, with a cohesion value of approximately 5.87 MPa. Meanwhile, the residual frictional resistance can be taken as approximately one-half of the ultimate resistance. The results of the finite-element analysis show that the trilinear model is reasonable to simulate the shear-slip laws of the embossed steel-grout interface and the rough concrete-grout interface.