Dynamic compressive strength model for rock-steel fiber-reinforced concrete composite layer
-
摘要: 为了研究冲击荷载下岩石-钢纤维混凝土(R-SFRC)复合层的抗压强度模型,利用分离式霍普金森压杆对花岗岩、混凝土和R-SFRC复合层进行动态冲击压缩试验,并通过回归试验结果得到R-SFRC复合层的对数型、幂函数型和强度-应变率依赖机制型3种强度模型,同时考虑R-SFRC复合层界面相互作用,基于Mohr-Coulomb强度准则建立复合层动态抗压强度计算模型。结果表明,R-SFRC复合层动态抗压强度随应变率及钢纤维掺量增大而增大;3种回归模型拟合复合层动态抗压强度试验结果的相关系数范围为0.918~0.999,其中依赖机制型模型与试验结果的相关性最大;基于Mohr-Coulomb强度准则的3种模型得到的复合层抗压强度计算值相对试验值的误差范围为-9.23%~3.16%,对数型模型的误差最大值较小。R-SFRC复合层动态抗压强度计算模型可为混凝土支护隧道围岩设计提供理论基础。Abstract: In order to study the compressive strength model for rock-steel fiber-reinforced concrete (R-SFRC) composite layer under impact loading, the dynamic impact compression tests on the granite, concrete and R-SFRC composite layer are carried out by using the separated Hopkinson pressure bar to obtain the dynamic compressive strengths of different materials. With the regression fitting of the test results, three types of strength models for the R-SFRC composite layer called logarithmic, power function and strength-strain rate dependent mechanism are obtained, and the dynamic compressive strength models for the R-SFRC composite layer are established based on the Mohr-Coulomb strength criterion considering the interface interaction of the R-SFRC composite layer. The results show that the dynamic compressive strength of the R-SFRC composite layer increases with the increase of the strain rate and steel fiber content, and the range of the correlation coefficient of three regression models is 0.918~0.999, and the R2 of the dependent mechanism model is the largest. The error range of the theoretical value of the dynamic compressive strength calculated based on the Mohr-Coulomb strength criterion relative to the test value is -9.23%~3.16%, and the maximum error value of the logarithmic model is the smallest. The computational model for the dynamic compressive strength of the R-SFRC composite layer can provide a theoretical basis for the design of the surrounding rock of concrete-supported tunnels.
-
-
表 1 花岗岩的物理及力学性能
Table 1 Physical and mechanical properties of granite
密度/
(kg·m-3)弹性模量/
GPa单轴抗压强度/MPa 泊松比 内摩擦角/(°) 3000 67.41 187.1 0.207 53 表 2 钢纤维的物理及力学性能
Table 2 Physical and mechanical properties of steel fiber
长度/
mm直径/
mm密度/
(kg·m-3)抗拉强度/
MPa弹性模量/
GPa35 0.3 7850 1150 220 表 3 混凝土配合比
Table 3 Mixture proportions of concrete
单位: kg/m3 材料类型 水泥 水 细骨料 粗骨料 减水剂 钢纤维 FC0 418 182 611 1239 4.18 0 FC4 418 182 611 1239 4.18 40 FC6 418 182 611 1239 4.18 60 FC8 418 182 611 1239 4.18 80 注:FC4,FC6和FC8分别表示钢纤维掺量为40,60,80 kg/m3的钢纤维混凝土。 表 4 回归模型中R-SFRC复合层的参数拟合值
Table 4 Fitting values of parameters of R-SFRC composite layer using regression models
复合层类型 对数型 幂函数型 依赖机制型 k1 k2 k4 R-FC0 1.132 -0.608 0.996 0.356 0.991 0.833 61.348 2.731 0.999 R-FC4 0.998 -0.207 0.963 0.362 0.980 3.873 364.699 1.198 0.998 R-FC6 1.001 -0.172 0.942 0.382 0.918 3.623 298.722 1.196 0.971 R-FC8 1.100 -0.456 0.979 0.378 0.977 1.584 108.280 1.392 0.993 表 5 回归模型中混凝土的参数拟合值
Table 5 Fitting values of parameters of concrete using regression models
材料类型 对数型 幂函数型 依赖机制型 FC0 0.842 -0.357 0.941 0.287 0.961 0.476 81.603 4.923 0.988 FC4 0.940 -0.448 0.957 0.309 0.961 0.494 64.627 5.211 0.980 FC6 1.031 -0.516 0.947 0.334 0.966 0.725 68.548 3.012 0.972 FC8 1.038 -0.530 0.987 0.333 0.989 0.784 71.679 2.734 0.998 表 6 R-SFRC复合层的动态抗压强度计算值与试验值对比
Table 6 Comparison of calculated and tested values of dynamic compressive strength of R-SFRC composite layer
复合层类型 应变率/s-1 /MPa /MPa /MPa /MPa /% /% /% R-FC0 38.3 82.5±1.1 75.1 75.0 81.0 -8.93 -9.09 -1.87 55.4 94.2±3.0 89.5 88.2 85.5 -5.02 -6.33 -9.23 72.1 105.6±2.5 98.5 97.7 96.0 -6.77 -7.48 -9.08 97.2 114.6±6.4 105.9 106.3 107.4 -7.62 -7.27 -6.31 111.5 118.4±4.0 110.3 111.7 112.3 -6.87 -5.65 -5.17 R-FC4 33.9 88.8±4.3 82.8 83.4 83.9 -6.76 -6.03 -5.50 57.6 99.2±3.0 97.6 96.7 94.4 -1.59 -2.54 -4.83 73.5 109.9±5.8 105.9 104.9 106.9 -3.66 -4.52 -2.76 94.1 119.3±5.9 115.9 115.9 118.0 -2.86 -2.85 -1.13 115.9 129.6±4.6 121.9 123.1 120.8 -5.91 -5.03 -6.80 R-FC6 34.5 99.2±3.5 91.0 92.1 91.3 -8.28 -7.20 -8.01 58.1 109.7±4.9 106.3 105.4 103.5 -3.13 -3.88 -5.67 72.6 114.2±4.9 117.8 116.8 117.1 3.16 2.31 2.51 93.8 129.8±5.3 128.3 128.2 128.6 -1.16 -1.19 -0.95 116.3 135.6±5.4 133.8 134.7 133.2 -1.33 -0.68 -1.78 R-FC8 38.5 100.7±0.6 94.4 95.3 95.2 -6.26 -5.38 -5.51 53.7 112.7±2.7 109.2 108.3 113.3 -3.12 -3.92 0.56 76.5 121.5±4.0 119.7 118.6 119.3 -1.50 -2.40 -1.78 93.0 135.2±6.4 131.6 131.5 132.6 -2.67 -2.75 -1.91 114.4 140.7±5.7 138.9 140.0 139.0 -1.31 -0.49 -1.24 注:为R-SFRC复合层的动态抗压强度试验值;,和分别为基于Mohr-Coulomb强度准则建立的对数型、幂函数型和强度-应变率依赖机制型模型的R-SFRC复合层动态抗压强度计算值。为的误差,,=1,2,3。 -
[1] 郭东明, 闫鹏洋, 凡龙飞, 等. 喷层混凝土-围岩组合体波动特性及动力特性研究[J]. 振动与冲击, 2018, 37(24): 85-91, 136. GUO Dongming, YAN Pengyang, FAN Longfei, et al. A study on the stress wave characteristics and dynamic mechanical property of the sprayed concrete-surrounding rock combined body[J]. Journal of Vibration and Shock, 2018, 37(24): 85-91, 136. (in Chinese)
[2] JIANG Q, YANG Y, YAN F, et al. Deformation and failure behaviours of rock-concrete interfaces with natural morphology under shear testing[J]. Construction and Building Materials, 2021, 293: 123468. doi: 10.1016/j.conbuildmat.2021.123468
[3] MOUZANNAR H, BOST M, LEROUX M, et al. Experimental study of the shear strength of bonded concrete–rock interfaces: surface morphology and scale effect[J]. Rock Mechanics and Rock Engineering, 2017, 50(10): 2601-2625. doi: 10.1007/s00603-017-1259-2
[4] CHANG X, LU J Y, WANG S Y, et al. Mechanical performances of rock-concrete bi-material disks under diametrical compression[J]. International Journal of Rock Mechanics and Mining Sciences, 2018, 104: 71-77. doi: 10.1016/j.ijrmms.2018.02.008
[5] ZHU J B, BAO W Y, PENG Q, et al. Influence of substrate properties and interfacial roughness on static and dynamic tensile behaviour of rock-shotcrete interface from macro and micro views[J]. International Journal of Rock Mechanics and Mining Sciences, 2020, 132: 104350. doi: 10.1016/j.ijrmms.2020.104350
[6] ZHAO B Y, LIU Y, LIU D Y, et al. Research on the influence of contact surface constraint on mechanical properties of rock-concrete composite specimens under compressive loads[J]. Frontiers of Structural and Civil Engineering, 2020, 14(2): 322-330. doi: 10.1007/s11709-019-0594-7
[7] 陈猛, 王浩, 齐迈, 等. 岩石–钢纤维混凝土复合层动态压缩性能试验研究[J]. 岩石力学与工程学报, 2020, 39(6): 1222-1230. CHEN Meng, WANG Hao, QI Mai, et al. Experimental study on dynamic compressive properties of composite layers of rock and steel fiber reinforced concrete[J]. Chinese Journal of Rock Mechanics and Engineering, 2020, 39(06): 1222-1230. (in Chinese)
[8] 赵坚, 李海波. 莫尔-库仑和霍克-布朗强度准则用于评估脆性岩石动态强度的适用性[J]. 岩石力学与工程学报, 2003, 22(2): 171-176. doi: 10.3321/j.issn:1000-6915.2003.02.001 ZHAO Jian, LI Haibo. Estimating the dynamic strength of rock using Mohr-coulomb and hoek-brown criteria[J]. Chinese Journal of Rock Mechanics and Engineering, 2003, 22(2): 171-176. (in Chinese) doi: 10.3321/j.issn:1000-6915.2003.02.001
[9] 宫凤强, 司雪峰, 李夕兵, 等. 基于应变率效应的岩石动态Mohr-Coulomb准则和Hoek-Brown准则研究[J]. 中国有色金属学报, 2016, 26(8): 1763-1773. GONG Fengqiang, SI Xuefeng, LI Xibing, et al. Rock dynamic Mohr-Coulomb and Hock-Brown criteria based on strain rate effect[J]. The Chinese Journal of Nonferrous Metals, 2016, 26(8): 1763-1773. (in Chinese)
[10] 宫凤强, 陆道辉, 李夕兵, 等. 不同应变率下砂岩动态强度准则的试验研究[J]. 岩土力学, 2013, 34(9): 2433-2441. GONG Fengqiang, LU Daohui, LI Xibing, et al. Experimental research of sandstone dynamic strength criterion under different strain rates[J]. Rock and Soil Mechanics, 2013, 34(9): 2433-2441. (in Chinese)
[11] 钱七虎, 戚承志. 岩石、岩体的动力强度与动力破坏准则[J]. 同济大学学报(自然科学版), 2008, 36(12): 1599-1605. doi: 10.3321/j.issn:0253-374X.2008.12.001 QIAN Qihu, QI Chengzhi. Dynamic strength and dynamic fracture criteria of rock and rock mass[J]. Journal of Tongji University (Natural Science), 2008, 36(12): 1599-1605. (in Chinese) doi: 10.3321/j.issn:0253-374X.2008.12.001
[12] GONG F Q, SI X F, LI X B, et al. Dynamic triaxial compression tests on sandstone at high strain rates and low confining pressures with split Hopkinson pressure bar[J]. International Journal of Rock Mechanics and Mining Sciences, 2019, 113: 211-219. doi: 10.1016/j.ijrmms.2018.12.005
[13] SI X F, GONG F Q, LI X B, et al. Dynamic Mohr–Coulomb and Hoek–Brown strength criteria of sandstone at high strain rates[J]. International Journal of Rock Mechanics and Mining Sciences, 2019, 115: 48-59. doi: 10.1016/j.ijrmms.2018.12.013
[14] FU Q, XU W R, HE J Q, et al. Dynamic strength criteria for basalt fibre-reinforced coral aggregate concrete[J]. Composites Communications, 2021, 28: 100983. doi: 10.1016/j.coco.2021.100983
[15] LU D C, WANG G S, DU X L, et al. A nonlinear dynamic uniaxial strength criterion that considers the ultimate dynamic strength of concrete[J]. International Journal of Impact Engineering, 2017, 103: 124-137. doi: 10.1016/j.ijimpeng.2017.01.011
[16] ZHAO B Y, LIU Y, HUANG T Z, et al. Experimental study on strength and deformation characteristics of rock–concrete composite specimens under compressive condition[J]. Geotechnical and Geological Engineering, 2019, 37(4): 2693-2706. doi: 10.1007/s10706-018-00787-9
[17] 陈猛, 崔秀文, 颜鑫, 等. 岩石-钢纤维混凝土复合层抗压强度预测模型[J]. 岩土力学, 2021, 42(3): 638-646. CHEN Meng, CUI Xiuwen, YAN Xin, et al. Prediction model for compressive strength of rock-steel fiber reinforced concrete composite layer[J]. Rock and Soil Mechanics, 2021, 42(3): 638-646. (in Chinese)
[18] ZHANG X H, CHIU Y W, HAO H, et al. Dynamic compressive properties of Kalgoorlie basalt rock[J]. International Journal of Rock Mechanics and Mining Sciences, 2020, 135: 104512. doi: 10.1016/j.ijrmms.2020.104512
[19] 袁良柱, 苗春贺, 单俊芳, 等. 冲击下混凝土试样应变率效应和惯性效应探讨[J]. 爆炸与冲击, 2022, 42(1): 1-13. YUAN Liangzhu, MIAO Chunhe, SHAN Junfang, et al. On strain-rate and inertia effects of concrete samples under impact[J]. Explosion and shock waves, 2022, 42(1): 1-13. (in Chinese)
[20] FENG S W, ZHOU Y, WANG Y, et al. Experimental research on the dynamic mechanical properties and damage characteristics of lightweight foamed concrete under impact loading[J]. International Journal of Impact Engineering, 2020, 140: 103558. doi: 10.1016/j.ijimpeng.2020.103558
[21] 王健, 李二兵, 谭跃虎, 等. 层状盐岩及泥岩夹层动态力学特性对比试验研究[J]. 岩石力学与工程学报, 2017, 36(12): 3002-3011. WANG Jian, LI Erbing, TAN Yuehu, et al. Comparative experimental study on dynamic mechanical properties of bedded salt rock and mudstone interbed[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(12): 3002-3011. (in Chinese)
[22] LI X Z, QI C Z. A micro-macro dynamic compressive-shear fracture model under static confining pressure in brittle rocks[J]. International Journal of Impact Engineering, 2018, 122: 109-118. doi: 10.1016/j.ijimpeng.2018.07.010
[23] ZHAO J, LI H B, WU M B, et al. Dynamic uniaxial compression tests on a granite[J]. International Journal of Rock Mechanics and Mining Sciences, 1999, 36(2): 273-277. doi: 10.1016/S0148-9062(99)00008-X
-
其他相关附件