摘要
以光敏树脂为原材料设计制作了不同裂隙倾角的3D打印岩体试样,开展了单轴压缩试验并结合数字图像相关(Digital Image Correlation,DIC)技术对试样破坏模式、力学特性、能量演化和破裂机制进行分析。结果表明:单轴压缩荷载下,试样在预制裂隙端部萌生剪切裂纹或张拉裂纹,预制裂隙角度对试样破坏模式影响显著;试样应力应变曲线分为4段:压密、弹性变形、塑性变形和破坏段;试样峰值应力和弹性模量在裂隙倾角22.5°和90°时分别取得最小和最大值;试样能量演化曲线分为5段,即压密耗能、线性储能、能量跳跃积聚、弹性应变能释放和能量耗散段;加载初期试样存在不均匀应变区域,随着荷载增大,高应变带有规律地出现;试样上下翼起裂角相近且随预制裂隙倾角增加而有规律地减小;试样畸变能越大,承载能力越差。
3D printed rock specimens with different fracture inclination angles were designed and fabricated using photosensitive resin as raw material.Uniaxial compression tests were carried out and combined with Digital Image Correlation(DIC)technique to analyze the damage mode,mechanical properties,energy evolution and rupture mechanism of the specimens.The results showed that the specimens developed shear cracks or tension cracks at the end of the prefabricated fracture under uniaxial compression loading,and the angle of the prefabricated fracture had a significant effect on the damage mode of the specimens;Specimen stress-strain curves were divided into four segments:compression-density,elastic deformation,plastic deformation and damage segments;The specimen peak stress and elastic modulus achieved minimum and maximum values at the crack inclination angle of 22.5°and 90°,respectively;The energy evolution curve of the specimen is divided into 5 segments:compression-density energy dissipation,linear energy storage,energy jump accumulation,elastic strain energy release and energy dissipation segments;Uneven strain regions exist in the specimen at the beginning of loading,and high strain bands appear regularly as the load increases;the cracking angles of the upper and lower wings of the specimen are similar and decrease regularly with the increase of the prefabricated fracture inclination;The larger the distortion energy of the specimen,the weaker the bearing capacity.
作者
邢国华
罗小宝
秦拥军
刘彬
孙强
Xing Guohua;Luo Xiaobao;Qin Yongjun;Liu Bin;Sun Qiang(School of Civil Engineering Chang’an University,Xi’an 710061,P.R.China;School of Civil Engineering and Architecture Xinjiang University,Urumqi 830047,P.R.China;Xinjiang Construction Engineering(Group)Co.,Ltd.,Urumqi 830002,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2023年第4期1177-1187,1243,共12页
Chinese Journal of Underground Space and Engineering
基金
兵团国际科技合作计划项目(2019BC005)。
关键词
裂隙岩体
光敏树脂
3D打印
单轴压缩
能量演化
破裂机制
cracked rock mass
photosensitive resin
3D printing
uniaxial compression
energy evolution
cracking mechanism
