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In order to overcome the influence of shallow seas, low headroom and existing bridge structure on the construction of jet grouting piles, the construction technology of mobile working platform + jet grouting with connecting rods at sea was studied and put into practical application, based on the contraction practice of the East Artificial Island of Shenzhen-Zhongshan Link. Engineering practice shows that: 1) the construction technology of mobile working platform + jet grouting with connecting rods effectively solves the technical problems in jet grouting pile construction at sea and the working platform has a wider applicable range; 2) the dynamic speed control system based on theoretical calculation formulae can better ensure the quality of jet grouting pile construction, and the deviation rate of cement dosage is only 2.4% ; 3) the impact of the construction process on the existing bridge structure is mainly manifested in horizontal displacement in the down-bridge direction and the deformation value fluctuates in the range of -1.3 ~1.7 mm, which meets the high requirements for deformation control of extremely sensitive buildings (structures). [ABSTRACT FROM AUTHOR]

Scissor-like bridges can quickly build emergency channels after disasters and improve rescue efficiency. In view of the characteristics of poor stiffness and low material utilization of scissor-like elements（SLEs）, a new cable supported scissor-like deployable bridge（CSSDB）for emergency was proposed combined with cable supported system. In order to investigate the behavior of CSSDB, Karamba3D was adopted to establish the finite element model, and parametric analysis was carried out under the action of moving vehicle load, considering the struts’ length and numbers, the SLEs’ cross section, the initial prestress amplitude and the expansion angle. Besides, Galapagos was used to optimize the CSSDB with the minimum structural mass as the optimization objective. The results show that increasing struts’ number, struts’ length and initial prestress can effectively reduce the stress and deflection of SLEs, while the stress and deflection can be increased by increasing expansion angle. Increasing thickeness of SLEs’ cross section reduces stress and increases deflection instead, and the CSSDB’s performance is still dependent on bending of SLEs. The optimization reduces structural mass by 38.89%, and the stress and deflection of CSSDB are 0.25 and 0.2 times than that of the corresponding scissor-like bridge, which proves the superiority of the CSSDB. [ABSTRACT FROM AUTHOR]

：In order to build an island in the sea area of deep silt stratum under the existing expressway bridge and realize the purpose of filling construction to ensure the safety of the bridge, taking the construction of the east artificial island of Shenzhen Zhongshan Link as an example, the backfilling direction and thickness of the island reclamation were determined by numerical analysis method, and the key construction technology method of " constructing isolation steel sheet pile first, then laying sand quilt, and then backfilling sand symmetrically in layers" was proposed. Through the automatic monitoring of the whole process, it is found that the cumulative changes of settlement and displacement of expressway bridge piers are less than1mm, which realizes the safety protection of existing bridges by island reclamation construction in sea area. The results show that the construction technology of island reclamation in the sea area is feasible and the influence on the settlement of adjacent buildings is controllable. The research results can be used for reference for similar projects. [ABSTRACT FROM AUTHOR]

Based on the study of the existing pile driving barge at home and abroad, aiming at the needs of offshore wind turbine and pile foundation construction of sea crossing bridges, the super large pile driving barge with pile frame height of 133 m has been developed, which has made innovations in the optimization selection of main dimensions, the optimization design of pile frame system, and the improvement of hydraulic system. It provides a reference for the designing of similar ships. [ABSTRACT FROM AUTHOR]

Offshore piled wharves are usually connected to land area by approach bridge. The approach bridge structure isgenerally of high pile beam and plate type, and the superstructure forms the bridge deck system by erecting prestressed T beams. Due to the characteristics of a large weight and long span, the T beams are usually installed by crane ships. Therefore,the construction cost and safety risk are high. For Indonesia Shenhua Guohua Java 7 Power Plant Project, the maritime nonrotating synchronous double hoisting technology was applied to install T-beam. During the hoisting process, the lifting distance was adjusted by the ups and downs boom to control the installation position of T -beam, which effectively reduced the construction safety risks. It is the first application in the industry, and has achieved good economic and social benefits, which provides a reference basis for similar engineering construction. [ABSTRACT FROM AUTHOR]