Design And Fabrication Of C50 Segment Concrete Of Wuhan Yangtze River Tunnel

In the shield-driven tunnel, segment is the most important and pivotal construction member. Several precast segments and building blocks are assembled to the tunnel lining structure,the segment must satisfy strength and stiffness requirements of engineering structures and safety quality indicator of engineering, performance of segment is decisive for the shield tunneling of quality and service life.The paper relys on Wuhan scientific and technological research project and the Wuhan Yangtze River Tunnel Project,select appropriate materials based on C50 high-performance segment concrete, determine the C50 high-performance segment concrete mixing proportion by dense matrix accumulation method.Based the above mixing proportion, the paper systematic study the influence of steam-system key factors on the physical and mechanical properties of C50 high-performance segment concrete, discuss of the key factors range, made suggested steam curing system. The influence of steam-system key factors on the Long-term volume stability, including shrinkage and creep, of C50 high- performance concrete is systematic studied and the comprison expression between the internal humidity and self-contraction of C50 high-performance concrete is established in the Steam-environment. The paper systematic study the influence of steam-system key factors on the resistance to chloride ion diffusion properties of C50 high-performance segment concrete, analyze the relationship between chloride ion diffusion coefficient and associated factor by gray relational analysis method, identify the main impact factors of concrete resistance to chloride ion permeability.To study the micro-structure formation process and the distribution of pore structure of C50 high-performance segment concrete, to find out the influence regular pattern of the composition, structure and durability of C50 high-performance segment concrete.The program is used in segment production of Wuhan Yangtze River Tunnel. The production segment has been used in Wuhan Yangtze River Tunnel. Segment appearance tactful formation, consistent color, small bubbles, the segment assembled to meet the quality requirements of the design, no crack appear under the largest 280t pressure, proved good quality.