Development of a new type of foam concrete and its application on stability analysis of large-span soft rock tunnel

Abstract

The long-term stability of large-span soft rock tunnel is influenced greatly by the creep effect of surrounding rock. The development of a new type of foam concrete which has the property of high compressibility and low ductility was introduced. And it was made as filling material of reserved deformation layer between the first lining and the second lining used in large-span soft rock tunnel. The effect of the new type of foam concrete was simulated as filling material of reserved deformation layer using numerical simulation. Through the comparison with the common large-span soft rock tunnel, the vault settlement and surrounding convergence are reduced by about 61% and 45%, respectively, after creep of 100 a. And in the second lining, the plastic zone reduces apparently and the maximum equivalent plastic strain decreases relatively. So, it can be found that the application of the new type of foam concrete as the filling material of reserved deformation layer can relieve the excessive force in second lining induced by rock creep, reduce its deformation and improve the stability of tunnel.

Keywords

foam concrete / large-span soft rock tunnel / stability analysis / numerical simulation

References

[1] QuH.-feng.. An overview on construction and research of super-large cross-section tunnels with low height-span ratios [J]. Tunnel Construction, 2009, 292: 166-171

[2] CaiX., LiH.-x., WuY.-l., YiJ.-gang.. Optimal design of structure of underwater tunnels [J]. Journal of Hohai University: Natural Sciences, 2009, 376: 665-668

[3] ZhouD.-h., CaoL.-q., MaY.-feng.. Research on construction behaviors of support system in four-lane ultra large-span tunnel with super-large cross-section [J]. Chinese Journal of Rock Mechanics and Engineering, 2010, 29(1): 140-148

[4] REN G, SMITH J V, TANG J W, XIE Y M. Underground excavation shape optimization using an evolutionary procedure [J]. Computers and Geotechnics, 2005, (32): 122–132.

[5] MiuraK., YagiH., ShiromaH., TakekuniK.. Study on design and construction method for the New Tomei-Meishin expressway tunnels [J]. Tunnelling and Underground Space Technology, 2003, 18(2/3): 271-281

[6] BroxD., HagedornH.. Extreme deformation and damage during the construction of large tunnels [J]. Tunnelling and Underground Space Technology, 1999, 14(1): 23-28

[7] NoS.-l., NohS.-h., LeeS.-p., SeoJ.-woo.. Construction of long and large twin tube tunnel in Korea-Sapaesan tunnel [J]. Tunnelling and Underground Space Technology, 2006, 21(3/4): 393

[8] BartonN.. Model study of very large underground openings at shallow depth [C]. Proc 4th Congress International Society for Rock Mechanics. Montreux, Switzerland, 1979, 1: 583-590

[9] MIURA K. Design and construction of mountain tunnels in Japan [J]. Tunnelling and Underground Space Technology, 2003, (18): 115–126.

[10] WilliamsI., OsborneN., ThaiA. E.. Recent large-diameter tunnel construction in Singapore using sprayed concrete linings [J]. Tunnelling and Underground Space Technology, 1999, 14(4): 527-538

[11] YangW.-b., XueX.-cheng.. The optimized calculation method for spacing and cross section of underground tunnels [J]. Chinese Journal of Geotechnical Engineering, 2001, 231: 61-63

[12] SunJun.. Rock rheological mechanics and its advance in engineering applications [J]. Chinese Journal of Rock Mechanics and Engineering, 2007, 26(6): 1081-1106

[13] Gasc-barbierM., ChancholeS., BÉRESTP.. Creep behavior of Bure clayey rock [J]. Applied Clay Science, 2004, 26(1/2/3/4): 449-458

[14] HeapM. J., BaudP., MeredithP. G., VinciguerraS., BellA. F., MainI. G.. Brittle creep in basalt and its application to time-dependent volcano deformation [J]. Earth and Planetary Science Letters, 2011, 307(1/2): 71-82

[15] WangD.-k., WeiJ.-p., YinG.-z., WangY.-g., WenZ.-hui.. Triaxial creep behavior of coal containing gas in laboratory [J]. Procedia Engineering, 2011, 26: 1001-1010

[16] NaumannM., HunscheU., SchulzeO.. Experimental investigations on anisotropy in dilatancy, failure and creep of opalinus clay [J]. Physics and Chemistry of the Earth, 2007, 32(8–14): 889-895

[17] WangJ.-c., ChenY.-kai.Application of Abaqus in civil engineering [M], 2006ZhejiangZhejiang University Press34-86

[18] GibsonL. J., AshbyM. F.. The mechanics of three-dimensional cellular materials [J]. Proceedings of the Royal Society, 1982, 382(1782): 43-59

[19] MaitisK., GibsonL. J., AshbyM. F.. Deformation and energy absorption diagrams for cellular solids [J]. Acta Metallurgica, 1984, 32(11): 1963-1975