【摘要】：本文以銀百高速(G69)羅圈溝段義子頭滑坡為研究對象,概述了滑坡所在地的氣象水文、地形地貌、地層巖性、地質構造等工程地質條件,并通過前期的資料收集、野外實地調繪、鉆探及室內試驗等手段,對滑坡穩(wěn)定性和變形機理進行研究,采用極限平衡法對該滑坡進行了穩(wěn)定性評價和滑坡下滑推力計算,同時對該滑坡進行二維數值模擬,得到其應力、應變、位移云圖及穩(wěn)定性系數、,最后結合滑坡與實際工程的關系對該滑坡進行了治理設計并對該治理方案進行數值模擬,以此來驗證具體治理設計方法的合理性。論文的主要研究內容和研究成果如下:(1)根據野外滑坡工程地質調繪和勘探可知,按滑體規(guī)模及物質組成劃分,義子頭滑坡屬于巨型黃土滑坡。義子頭滑坡在平面上呈簸箕狀,滑體中下部較厚,上部較薄,整體形態(tài)清晰明顯,滑坡表面呈臺階狀的一面坡延伸至滑坡前緣,在滑體中后部可見多個次級滑坎及串珠狀落水洞、張拉裂縫等。(2)采用極限平衡法對該滑坡在天然工況和降雨工況下分別進行了穩(wěn)定性計算,由穩(wěn)定性結果知,在正常工況下,兩剖面整體都處于基本穩(wěn)定~穩(wěn)定狀態(tài);在降雨工況下,Ⅰ—Ⅰ’剖面前部的次級滑面處于不穩(wěn)定狀態(tài),Ⅱ—Ⅱ’剖面后部的沿路基邊坡的新剪出口處于不穩(wěn)定狀態(tài)。(3)使用Midas/GTS對該滑坡的兩個剖面進行二維模擬分析,得到其應力、應變、位移云圖及穩(wěn)定性系數,分析后可知,該滑坡Ⅰ—Ⅰ’剖面的應變和位移主要集中在滑坡前部的次級滑面處,Ⅱ—Ⅱ’剖面的應變和位移主要集中在路基邊坡處的新剪出口。對比極限平衡法的結果可知數值模擬結果與其基本吻合。(4)根據滑坡治理原則和該滑坡的基本特征并結合與公路的關系等,確定對義子頭滑坡采用抗滑樁+削方,并對該治理方案進行數值模擬,結果顯示相對于滑坡治理前滑體的應變和位移都大大減小,且樁頂位移小于允許位移量,滑坡穩(wěn)定性系數明顯提高,滑坡處于穩(wěn)定狀態(tài)。這些都表明該滑坡的治理方案合理、防護效果較好。數值模擬同時得到了該滑坡抗滑樁的剪力和彎矩云圖,從云圖中可以直觀的看到抗滑樁在滑面附近和錨固段中部的內力最大,這可以用于指導抗滑樁的配筋計算。
[Abstract]:Taking Yizitou landslide in Luohuangou section of YinbaiExpressway (G69) as the research object, this paper summarizes the engineering geological conditions such as meteorology and hydrology, topography and geomorphology, stratigraphic lithology, geological structure and other engineering geological conditions in the site of the landslide. The stability and deformation mechanism of the landslide are studied by means of field mapping, drilling and laboratory test. The stability evaluation and slide thrust calculation of the landslide are carried out by using the limit equilibrium method. At the same time, the stress, strain, displacement cloud map and stability coefficient of the landslide are obtained by two-dimensional numerical simulation. Finally, the control design of the landslide and the numerical simulation of the treatment scheme are carried out in the light of the relationship between the landslide and the actual engineering. To verify the rationality of the specific governance design method. The main research contents and results are as follows: (1) according to the field landslide engineering geological survey and exploration, according to the size and material composition of the landslide, Yizitou landslide belongs to the giant loess landslide. The Yizitou landslide is dustpan shape on the plane, the middle and lower part of the slide body is thicker, the upper part is thinner, the whole form is clear and obvious, and the slope on the surface of the landslide extends to the front edge of the landslide. In the middle and back of the slider, there are many secondary sliders and beaded caverns, tension cracks and so on. (2) the stability of the landslide under natural and rainfall conditions is calculated by using the limit equilibrium method, and the results of stability are obtained. Under normal working conditions, the whole of the two sections is in a stable to stable state. Under rainfall conditions, the secondary slip surface in front of 鈪，

本文編號：2343113