CAJ | 학술논문

膝状挠曲破碎带是某水电站坝基的主要工程地质问题。破碎带岩性为完整性较差的碎裂、碎屑软弱砂岩，并呈现孔隙式胶结接触，其工程力学特性对坝基变形和稳定存在巨大影响。基于破碎带砂岩组织结构疏松、含水率较高、物理力学性能较差等特点，首先开展了基本物理特性试验分析，认为岩石微细观结构复杂、渗透特性较好，属小孔隙率砂岩。其次，开展了室内常规和现场力学特性试验研究；最后，在宏观力学参数确定的基础上，探讨了破碎带对工程作用的响应及影响。结果表明，破碎带岩石内部结构破坏严重，矿物成分主要为石英、长石、绢云母等，化学成分以 SiO2为主，但化学侵蚀并不显著。常规剪切曲线呈现出明显的4阶段特征，三轴压缩试验破坏机制为塑性剪切破坏，表现出强度低、延性扩容明显、出现屈服平台等特征，且碎裂岩强度略高于碎屑岩；现场试验表明岩体变形均匀，变形模量较低，处于60～630 MPa；地基承载力处于0.8～2.3 MPa。研究成果对该水电站坝基工程有重要的参考价值。
슬상뇨곡파쇄대시모수전참패기적주요공정지질문제。파쇄대암성위완정성교차적쇄렬、쇄설연약사암，병정현공극식효결접촉，기공정역학특성대패기변형화은정존재거대영향。기우파쇄대사암조직결구소송、함수솔교고、물리역학성능교차등특점，수선개전료기본물리특성시험분석，인위암석미세관결구복잡、삼투특성교호，속소공극솔사암。기차，개전료실내상규화현장역학특성시험연구；최후，재굉관역학삼수학정적기출상，탐토료파쇄대대공정작용적향응급영향。결과표명，파쇄대암석내부결구파배엄중，광물성분주요위석영、장석、견운모등，화학성분이 SiO2위주，단화학침식병불현저。상규전절곡선정현출명현적4계단특정，삼축압축시험파배궤제위소성전절파배，표현출강도저、연성확용명현、출현굴복평태등특정，차쇄렬암강도략고우쇄설암；현장시험표명암체변형균균，변형모량교저，처우60～630 MPa；지기승재력처우0.8～2.3 MPa。연구성과대해수전참패기공정유중요적삼고개치。
The knee-shaped deflection fractured zone located in the dam-foundation of a hydropower station is a main engineering geological problem of the project. The lithology is soft sandstone with poor integrity and pore cementation contact, which composed by cataclastic rock and clastic rock. The engineering mechanical properties of sandstone may have a significant impact on the deformation and stability of the dam. Based on the characteristics of loose organizational structure, high moisture content and poor physical mechanical properties, the basic physical properties tests are carried out to fractured zone sandstone first. It's considered the sandstone which is extremely complex microstructure and good permeability as small porosity sandstone. Secondly, the conventional and field tests are carried out to study mechanical properties. Finally, the influences of the fractured zone are discussed based on a certain macromechanical parameter. The results show that, the internal structure of sandstone is damage seriously;and main mineral compositions are quartz, feldspar, sericite and so on;the main chemical constituent is SiO2;but the chemical erosion is not significant. The shear curve shows the characteristics of four distinct stages. The failure mechanism of triaxial compression test is plastic shearing;and the curve shows a low strength, significantly ductility dilatancy;and yield platform is formed. Also the cataclastic rock strength is slightly higher than clastic rock. The field tests show that the deformation of rock mass is uniform, but the deformation modulus is low of which the range is 60-630 MPa. And the foundation bearing capacity ranges from 0.8-2.3 MPa. The research results provide greatly referential value for dam foundation of hydropower station.