高级检索

胡世杰,王方田,高 翔,等. 三向应力状态下超高水材料固结体损伤特征及力学特性研究[J]. 煤炭科学技术,2022,50(12):128−135

. DOI: 10.13199/j.cnki.cst.2021-0392
引用本文:

胡世杰,王方田,高 翔,等. 三向应力状态下超高水材料固结体损伤特征及力学特性研究[J]. 煤炭科学技术,2022,50(12):128−135

. DOI: 10.13199/j.cnki.cst.2021-0392

HU Shijie,WANG Fangtian,GAO Xiang,et al. Damage characteristics and mechanical properties of superhigh-water material consolidated body under triaxial stress[J]. Coal Science and Technology,2022,50(12):128−135

. DOI: 10.13199/j.cnki.cst.2021-0392
Citation:

HU Shijie,WANG Fangtian,GAO Xiang,et al. Damage characteristics and mechanical properties of superhigh-water material consolidated body under triaxial stress[J]. Coal Science and Technology,2022,50(12):128−135

. DOI: 10.13199/j.cnki.cst.2021-0392

三向应力状态下超高水材料固结体损伤特征及力学特性研究

Damage characteristics and mechanical properties of superhigh-water material consolidated body under triaxial stress

  • 摘要: 为研究超高水材料固结体在三向应力状态下的损伤特征及力学特性,进行不同养护时间(1、7、14、21、28 d)下超高水材料固结体的单轴压缩试验。借助PFC3D的平行黏结模型建立不同养护时间下的单轴压缩模型,得出与单轴试验强度相符合的5组PFC3D单轴压缩模拟试验强度。并统计各组平行黏结模型的细观物理力学参数,依据所得参数建立不同养护时间下超高水固结体的三轴压缩模型,施加与轴向应力相等的围压,记录不同养护时间下三轴试验过程中的应力-应变曲线及破坏时的力链分布。分析了超高水固结体在三向应力状态下的损伤特征,研究结果表明:①超高水材料固结体三向应力状态下的极限强度随养护时间的变化规律可由波尔茨曼方程表示。养护时间1~14 d时,极限强度增长最快;养护时间28 d时达到最大极限强度3.1 MPa。②超高水材料固结体三轴压缩模型力链贯通程度随养护时间的变化规律为:养护时间1~28 d,横向接触力链数目分别为4 006、4 561、4 891、5 017、5 062;纵向接触力链数目为4 029、4 439、4 716、4 917、5 123。表明超高水材料固结体的承载能力随养护时间的增加而增强,在养护时间0~14 d增长最快,14~28 d时承载能力趋于稳定。③以受拉力链模拟超高水材料固结体三轴压缩模型破坏过程中的裂隙发育过程,得出养护时间为1 d的超高水材料固结体破坏时的裂隙主要集中试样的上下两端。随着养护时间的增加,裂隙的发育程度增加,破坏时试样的中部开始出现裂隙,与上下两端的裂隙逐步贯通。

     

    Abstract: In order to study the damage characteristics of superhigh-wate consolidated body under triaxial stress state, uniaxial experiments of superhigh-water consolidated body under different curing time (1, 7, 14, 21, 28 d) were carried out. Uniaxial compression models under different curing times were established by the parallel bonding model of PFC3D, and five groups of uniaxial strength of PFC3D simulation experiment were obtained, which were consistent with the uniaxial strength of the uniaxial experiment. Statistics each simulation experiment of uniaxial compression parallel bond, mesoscopic physical and mechanical parameters in the model on the basis of the parameters under different curing time, superhigh-water consolidation triaxial compression model body, the same confining pressure and axial stress is applied, record the triaxial experiments under different curing time in the process of stress-strain curve and the force when the damage distribution chain. Analyzed superhigh-water body of consolidation in the damage characteristics of three to the stress state, the results show that: ① the superhigh-water concretion body three to the stress state of the changing rule of the ultimate strength with curing time can be represented by the Bohr boltzmann equation. When curing time is 1 to 14 days, the ultimate strength increases fastest, and the maximum ultimate strength reaches 3.1 MPa when curing time is 28 days. ② The variation rule of the degree of penetration of force chains in the triaxial compression model of superhigh-water consolidated body with curing time is as follows: within curing time of 1-28 d, the number of transverse contact force chains is 4 006, 4 561, 4 891, 5 017, 5 062, respectively. The number of longitudinal contact force chains is 4 029, 4 439, 4 716, 4 917 and 5 123. The results show that the carrying capacity of the superhigh-water consolidated body increases with the increase of curing time, and increases fastest during the curing time from 0 to 14 days, and tends to be stable during 14 to 28 days. ③ The tensile chain was used to simulate the fracture development in the triaxial compression model of superhigh-water consolidated body. The results show that the cracks concentrate on the upper and lower ends of the specimen when the curing time is 1 d. With the increase of curing time, the cracks in the middle of the specimen begin to increase and finally connect with the cracks at the upper and lower ends of the specimen.

     

/

返回文章
返回