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Abstract: The beam element in FLAC^3D can be used to simulate the supporting arch in a tunnel. However, this approach has the shortcoming of its constitutive model, and the bearing capacity and surrounding rock supporting effect of the arch model will be significantly exaggerated. To simulate the supporting arch in tunnel engineering well, a new approach is proposed by improving the beam element. The yield criterion of the beam element subjected to compression-bending loads is established based on the now-available bearing capacity formulas of some typical compression-bending sections. In addition, the yield criterion is embedded in the FLAC^3D main program by using the FISH language, and the modification of the beam model and the yielding failure simulation of the supporting arch are finally implemented. Compression-bending tests and roadway tunnel arch support example analysis were performed. The results are as follows: (1) the modified model showed the dependence of the bending moment and axial force on the yielding action of the beam element under compression-bending loads; (2) the implementation program is effective and sensitive; (3) the computing deviation caused by the shortcomings of the original beam element model was effectively suppressed, the mechanical behavior and surrounding rock supporting laws exhibited by the arch model were much closer to reality, and the calculation accuracy and design reliability were improved by the new simulation approach.

This manuscript gives a modified model of the Beam structure element in the commercial code of FLAC3D. The modified model can consider the yield not only on the bending behavior but also on the axial deformation. The modification procedure of the axial yielding of the Beam structure element is described clearly, and the modified Beam has a good performance when it is subjected a compression-bending load. An example analysis of roadway arch support using the modified Beam is given. According to the results, the difference between the modified Beam with unmodified Beam is obvious.

基于FLAC^3D梁单元修正的隧道/巷道拱架支护模拟方法

[1]Brady, B.H.G., Brown, E.T., 2004. Rock Mechanics for Underground Mining, 3rd Edition. Kluwer Academic Publishers, Dordrecht/Boston/London.

[2]Chang, X., Luo, X., Zhu, C.X., et al., 2014. Analysis of circular concrete-filled steel tube (CFT) support in high ground stress conditions. Tunnelling and Underground Space Technology, 43:41-48.

[3]Do, N.A., Dias, D., Oreste, P., 2014. Three-dimensional numerical simulation of mechanized twin stacked tunnels in soft ground. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 15(11):896-913.

[4]Fahimifar, A., Karami, M., Fahimifar, A., 2015. Modifications to an elasto-visco-plastic constitutive model for prediction of creep deformation of rock samples. Soils and Foundations, 55(6):1364-1371.

[5]Han, L.H., Yang, Y.F., 2007. Modern Steel Tube Confined Concrete Structures Technology. China Architecture & Building Press, Beijing, China, p.75-102 (in Chinese).

[6]Hegde, A.M., Sitharam, T.G., 2015. Three-dimensional numerical analysis of geocell-reinforced soft clay beds by considering the actual geometry of geocell pockets. Canadian Geotechnical Journal, 52(9):1396-1407.

[7]Itasca Consulting Group Inc., 2005. Fast Lagrangian Analysis of Continua in 3 Dimensions, Version 3.0, User’s Manual. Itasca Consulting Group, Inc.

[8]Jiao, Y.Y., Song, L., Wang, X.Z., et al., 2013. Improvement of the U-shaped steel sets for supporting the roadways in loose thick coal seam. International Journal of Rock Mechanics & Mining Sciences, 60:19-25.

[9]Latha, G.M., Garaga, A., 2012. Elasto-plastic analysis of jointed rocks using discrete continuum and equivalent continuum approaches. International Journal of Rock Mechanics and Mining Sciences, 53:56-63.

[10]Li, S.C., Feng, X.D., Li, S.C., 2013. Numerical model for the zonal disintegration of the rock mass around deep underground workings. Theoretical and Applied Fracture Mechanics, 67-68:65-73.

[11]Li, T.C., Lyu, L.X., Zhang, S.L., et al., 2015. Development and application of a statistical constitutive model of damaged rock affected by the load-bearing capacity of damaged elements. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 16(8):644-655.

[12]Li, W.T., Yang, N., Li, T.C., 2016. Implementation of bolt broken failure in FLAC^3D and its application. Chinese Journal of Rock Mechanics and Engineering, 35(4):753-767 (in Chinese).

[13]Liu, W., Alber, B., Zhao, Y., et al., 2016. Upper bound analysis for estimation of the influence of seepage on tunnel face stability in layered soils. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 17(11):886-902.

[14]Nemcik, J., Ma, S., Aziz, N., et al., 2014. Numerical modelling of failure propagation in fully grouted rock bolts subjected to tensile load. International Journal of Rock Mechanics and Mining Sciences, 71:293-300.

[15]Pourhosseini, O., Shabanimashcool, M., 2014. Development of an elasto-plastic constitutive model for intact rocks. International Journal of Rock Mechanics and Mining Sciences, 66:1-12.

[16]Qi, T.Y., Lu, S.L., Gao, B., 2004. Amended model of bolt element in FLAC and its application. Chinese Journal of Rock Mechanics and Engineering, 23(13):2197-2200 (in Chinese).

[17]Rodríguez, R., Díaz-Aguado, M.B., 2013. Deduction and use of an analytical expression for the characteristic curve of a support based on yielding steel ribs. Tunnelling and Underground Space Technology, 33:159-170.

[18]SAC (Standardization Administration of China), 2014. Technical Code for Concrete Filled Steel Tubular Structures, GB 50936-2014. China Construction Industry Press, Beijing, China (in Chinese).

[19]Schumacher, F.P., Kim, E., 2013. Modeling the pipe umbrella roof support system in a Western US underground coal mine. International Journal of Rock Mechanics and Mining Sciences, 60:114-124.

[20]Wang, C., Wang, Y., Lu, S., 2000. Deformational behaviour of roadways in soft rocks in underground coal mines and principles for stability control. International Journal of Rock Mechanics and Mining Sciences, 37(6):937-946.

[21]Wang, Q., Jiang, B., Li, S.C., et al., 2016a. Experimental studies on the mechanical properties and deformation & failure mechanism of U-type confined concrete arch centering. Tunnelling and Underground Space Technology, 51:20-29.

[22]Wang, Q., Jiang, B., Shao, X., et al., 2016b. Mechanical properties of square-steel confined-concrete quantitative pressure-relief arch and its application in a deep mine. International Journal of Mining, Reclamation and Environment, 30(5):438-460.

[23]Wang, S.H., Qi, J.L., Yu, F., et al., 2016. A novel modeling of settlement of foundations in permafrost regions. Geomechanics and Engineering, 10(2):225-245.

[24]Wong, L.N.Y., Fang, Q., Zhang, D., 2013. Mechanical analysis of circular tunnels supported by steel sets embedded in primary linings. Tunnelling and Underground Space Technology, 37:80-88.

[25]Wu, H.M., Shu, Y.M., Zhu, J.G., 2011. Implementation and verification of interface constitutive model in FLAC^3D. Water Science and Engineering, 4(3):305-316.

[26]You, C.A., 2000. Calculation Theory of Roadway Steel Support. China Coal Industry Publishing House, Beijing, China, p.45-67 (in Chinese).

[27]Yu, Y., Bathurst, R.J., Damians, I.P., 2016a. Modified unit cell approach for modelling geosynthetic-reinforced column-supported embankments. Geotextiles and Geomembranes, 44(3):332-343.

[28]Yu, Y., Bathurst, R.J., Allen, T.M., 2016b. Numerical modeling of the SR-18 geogrid reinforced modular block retaining walls. Journal of Geotechnical and Geoenvironmental Engineering, 142(5):04016003.