摘要
某水库蓄水之后,通过坝体表面变形测点监测到部分坝体表面持续抬升,造成大坝部分坝段下游坡马道上侧排水沟护砌块石受坝坡变形挤压存在倾斜现象,其中部分坝段倾斜严重。在现场调查的基础上,结合大坝安全监测与检测资料,考虑包括库水位变化、坝体渗流场变化、地形地貌、地层岩性及坝基岩体应力等因素,初步认定坝体表面抬升是由于坝基岩体在渗漏条件下吸水膨胀所致。进而通过现场坝基取样试验检测坝基岩体膨胀情况,并结合大型通用有限元软件ANSYS,采用等效热应变模拟坝基岩体膨胀特性,与实际观测资料进行对比,在修正的材料力学参数基础上,拟合了坝基岩体的膨胀系数,较好地模拟了坝体表面变形,验证了坝基岩体膨胀这一结论的合理性。
After the impoundment of a reservoir, some parts of the dam surface have persistent uplift discovered by the dam surface deformation measure points. The drainage ditch supporting block stone on the downstream slope berm of parts of the dam has been extruded to tilt, and some of them isin a severe situation. Based on the site survey, the cause of the partial uplift in the dam foundation is comprehensively analyzed according to the dam safety monitoring and testing data, including water level change, seepage field change, topographic features, stratum lithology and dam foundation rock mass stress. It is preliminarily determined that the foundation rock absorbed water and swelled under leakage situa- tion which caused the uplift of the dam surface. The expansion of dam foundation rock mass is examined by taking dam foundation rock samples. The large finite element analysis software ANSYS is also adopted to simulate the swelling prop- erties of the dam foundation rock mass using equivalent thermal strain simulation. The expansion coefficient of the dam foundation rock mass is fitted based on modified material mechanics parameters. The dam surface deformation is well simulated in line with real monitoring data, which confirms the conclusion that the dam foundation rock mass expanded is reasonable.
出处
《水电能源科学》
北大核心
2018年第2期97-100,155,共5页
Water Resources and Power
基金
国家重点研发计划(2016YFC0401601)
水利部公益性行业科研专项(201501033)
南京水利科学研究院基金项目(Y715008)
关键词
坝体抬升
膨胀
有限元方法
等效热应变
dam body uplift
swell
finite element method
equivalent thermal strain
