水利水电科技进展
水利水電科技進展
수이수전과기진전
ADVANCES IN SCIENCE AND TECHNOLOGY OF WATER RESOURCES
2015年
1期
67-72
,共6页
张丽%沈振中%赵斌%李栋梁
張麗%瀋振中%趙斌%李棟樑
장려%침진중%조빈%리동량
混凝土面板砂砾石坝%超高坝面板缝失效%饱和非饱和渗流理论%三维有限元法
混凝土麵闆砂礫石壩%超高壩麵闆縫失效%飽和非飽和滲流理論%三維有限元法
혼응토면판사력석패%초고패면판봉실효%포화비포화삼류이론%삼유유한원법
concrete-faced sand-gravel dam%slab joint local failure of a superhigh dam%saturated-unsaturated seepage theory%three-dimensional finite element method
为了掌握高水头作用下面板缝止水局部失效时坝体和坝基特别其垫层局部饱和区的渗流特性,针对拟建的某混凝土面板砂砾石坝,采用饱和非饱和渗流理论,拟定不同失效缝长、缝宽、位置和垫层渗透系数等情况,建立三维有限元模型,计算面板缝失效情况下坝体和坝基的渗流场,分析不同作用水头条件下面板缝不同失效程度对渗流场的影响。计算结果表明,某处面板缝小范围失效只对失效部位附近的渗流场产生较大影响,并导致局部渗透变形,而对坝体渗流场全局的影响不大;随着失效缝长、缝宽的加大,失效缝位置的降低和垫层渗透系数的增大,失效部位附近局部饱和区变大,其中,失效缝位置的影响最大,失效缝长的影响次之,失效缝宽的影响最小;当超高水头作用下面板缝通长失效时,坝体内浸润面显著升高,因此设计时应严格控制面板缝可能失效的范围,避免出现面板缝大范围失效。
為瞭掌握高水頭作用下麵闆縫止水跼部失效時壩體和壩基特彆其墊層跼部飽和區的滲流特性,針對擬建的某混凝土麵闆砂礫石壩,採用飽和非飽和滲流理論,擬定不同失效縫長、縫寬、位置和墊層滲透繫數等情況,建立三維有限元模型,計算麵闆縫失效情況下壩體和壩基的滲流場,分析不同作用水頭條件下麵闆縫不同失效程度對滲流場的影響。計算結果錶明,某處麵闆縫小範圍失效隻對失效部位附近的滲流場產生較大影響,併導緻跼部滲透變形,而對壩體滲流場全跼的影響不大;隨著失效縫長、縫寬的加大,失效縫位置的降低和墊層滲透繫數的增大,失效部位附近跼部飽和區變大,其中,失效縫位置的影響最大,失效縫長的影響次之,失效縫寬的影響最小;噹超高水頭作用下麵闆縫通長失效時,壩體內浸潤麵顯著升高,因此設計時應嚴格控製麵闆縫可能失效的範圍,避免齣現麵闆縫大範圍失效。
위료장악고수두작용하면판봉지수국부실효시패체화패기특별기점층국부포화구적삼류특성,침대의건적모혼응토면판사력석패,채용포화비포화삼류이론,의정불동실효봉장、봉관、위치화점층삼투계수등정황,건립삼유유한원모형,계산면판봉실효정황하패체화패기적삼류장,분석불동작용수두조건하면판봉불동실효정도대삼류장적영향。계산결과표명,모처면판봉소범위실효지대실효부위부근적삼류장산생교대영향,병도치국부삼투변형,이대패체삼류장전국적영향불대;수착실효봉장、봉관적가대,실효봉위치적강저화점층삼투계수적증대,실효부위부근국부포화구변대,기중,실효봉위치적영향최대,실효봉장적영향차지,실효봉관적영향최소;당초고수두작용하면판봉통장실효시,패체내침윤면현저승고,인차설계시응엄격공제면판봉가능실효적범위,피면출현면판봉대범위실효。
We applied saturated and unsaturated theory to establish a three dimensional finite element model ( FEM ) , based on a proposed concrete faced sand-gravel dam, aiming to simulate the seepage field of the dam and its foundation under the condition of slab joint local failure. The different length, width, and position of the slab joint local failure were combined in the simulation condition. Overall, the results showed that a single local failure of slab joint had large influence on the local seepage field around the slab joint failure and little influence on the entire seepage field. Additionally, the saturated field is enlarged by the increase of length and width of the slab joint failure and the decrease of the position, besides the seepage field is affected mostly by the position and minimally by the width. The results also revealed that the great increase of the saturated surface was caused by the slab joint full-length failure under the action of superhigh-head. Thus, these factors should be taken into consideration during the design in order to avoid large-scale failure of slab joint.