Gao Zongyu:Engineer and Designer of World-class Bridges

PLANNED in 2003,construction of the 1,092-meter-long ShanghaiNantong Railway Yangtze River Bridge–the world’s longest rail-cumroad cable-stayed steel bridge–started in 2014.On completion in 2019,it will span the 130 km.between the two cities,shortening to one hour the drive from Shanghai to Nantong.

Polyvinyl alcohol fiber cement-stabilized macadam:A review and performance evaluation

This review evaluated research results on polyvinyl alcohol fiber cement-stabilized macadam(PVA-FCSM)to further improve the long-term durability of road structures and promote its in-depth study and high-quality application.The suitable PVA fiber technical indexes for ordinary cement-stabilized macadam(CSM)were recommended.The difference in the mechanical properties between CSM and PVA-FCSM was described.The extent to which PVA fibers enhance the durability of CSM were clarified.Additionally,the mechanism of enhancement of CSM by PVA fibers was revealed.Finally,the performance of each type of fiber cement-stabilized macadam(FCSM)was compared and evaluated.The results indicated that the suggested PVA fiber length and content for CSM were 12-30 mm and 0.6-1.2 kg/m^(3),respectively.At different ages,the mean degree of improvement in the unconfined compressive strength was 14%,20%,and 14%,that in the compressive resilience modulus was 8%,11%,and 6%,and that in the splitting strength was 29%,15%,and 22%,respectively.At different ages,the mean degree of decreased in the dry shrinkage coefficient was 21%,16%,and 15%and that in the temperature shrinkage coefficient(20℃-30℃)was 23%,23%,and 18%,respectively.The coefficients increased with extended curing age.Moreover,at the same stress level,PVA-FCSM has a higher fatigue life compared to CSM.The bridging effect,high strength,and high modulus of PVA fiber enhance the strength and anti-cracking of CSM.The recommended fiber type for CSM is PVA fiber.