發(fā)布時(shí)間：2018-11-09 16:52

【摘要】：隨著山區(qū)高速公路的不斷發(fā)展,陡傾角的巖質(zhì)邊坡也越來(lái)越多,由于受地形地貌、地質(zhì)特征、降雨作用等多種因素的影響,其災(zāi)變破壞機(jī)理比較復(fù)雜,在工程建設(shè)的過(guò)程中,往往會(huì)因?yàn)閷?duì)其災(zāi)變破壞機(jī)理認(rèn)識(shí)的不足而導(dǎo)致防護(hù)工程的失敗。因而,深入開展陡傾巖質(zhì)邊坡災(zāi)變機(jī)理的研究,對(duì)于陡傾巖質(zhì)邊坡的風(fēng)險(xiǎn)評(píng)估、工程防護(hù)以及滑坡治理來(lái)說(shuō),有著非常重大的意義。本文以綦萬(wàn)高速公路K24+800段滑坡工程為依托,采用理論分析與數(shù)值模擬相結(jié)合的手段,對(duì)陡傾巖質(zhì)邊坡的災(zāi)變破壞機(jī)理及風(fēng)險(xiǎn)評(píng)估進(jìn)行了深入研究,得到的如下成果：①結(jié)合巖質(zhì)邊坡幾種常見(jiàn)的破壞類型,總結(jié)了影響陡傾巖質(zhì)邊坡穩(wěn)定性的因素,分析了陡傾巖質(zhì)邊坡的基本破壞模式、平面受力狀態(tài)以及其災(zāi)變破壞機(jī)理,認(rèn)為其是滑移一彎曲破壞,即屈服性破壞,并將其災(zāi)變破壞過(guò)程劃分為卸荷回彈、拉裂下錯(cuò)、擠壓彎曲與整體滑動(dòng)四個(gè)階段。②以綦萬(wàn)高速公路K24+800段滑坡工程為背景,系統(tǒng)地分析了滑坡區(qū)的水文地質(zhì)條件,闡述了滑坡的變形特征與結(jié)構(gòu)特征,對(duì)其變形破壞的原因進(jìn)行了深入的研究與分析。③選取K24+800段滑坡最為典型的Ⅲ-Ⅲ斷面,采用離散元程序UDEC對(duì)其災(zāi)變破壞的過(guò)程進(jìn)行了有效的模擬。通過(guò)對(duì)不同計(jì)算時(shí)步下坡體的最大不平衡力圖、速度矢量圖、位移矢量圖、應(yīng)力圖以及塑性區(qū)分布圖進(jìn)行綜合分析,總結(jié)出陡傾巖質(zhì)邊坡的破壞主要是剪切破壞,由于上部巖體沿軟弱面的滑移破壞導(dǎo)致了下部巖體的擠壓彎曲(剪切)破壞,最終造成了邊坡的整體失穩(wěn)。④基于模糊數(shù)學(xué)理論,選取了合適的評(píng)估指標(biāo),采用AHP法確定各分類指標(biāo)和基礎(chǔ)指標(biāo)的權(quán)重值,提出并建立了巖質(zhì)邊坡的二級(jí)模糊綜合評(píng)判模型,并用其對(duì)綦萬(wàn)高速公路K24+800段滑坡進(jìn)行風(fēng)險(xiǎn)評(píng)估,模型的最終評(píng)估結(jié)果與工程實(shí)際較為吻合,具有一定的指導(dǎo)意義。
[Abstract]:With the continuous development of highway in mountainous area, there are more and more rock slopes with steep dip angle. Due to the influence of many factors, such as topography, geological features, rainfall and so on, the catastrophic failure mechanism is quite complex, and in the process of engineering construction, The failure of protective engineering is often due to the lack of understanding of its catastrophic failure mechanism. Therefore, it is of great significance for the risk assessment, engineering protection and landslide control of steep slope to deeply study the catastrophic mechanism of steep dip rock slope. In this paper, based on the landslide engineering of K24,800 section of Qi-Wan Expressway, the catastrophic failure mechanism and risk assessment of steep inclined rock slope are deeply studied by means of theoretical analysis and numerical simulation. The results obtained are as follows: 1 combined with several common failure types of rock slope, the factors influencing the stability of steep dip rock slope are summarized, and the basic failure mode, plane stress state and catastrophic failure mechanism of steep dip rock slope are analyzed. It is considered that it is sliding bending failure, that is, yield failure, and the process of catastrophic failure is divided into four stages: unloading and springback, tension crack down fault, extrusion bending and integral sliding. 2. The landslide engineering of K24,800 section of Qiqi Expressway is taken as the background. The hydrogeological conditions of landslide area are systematically analyzed, the deformation and structural characteristics of landslide are expounded, and the causes of deformation and failure are deeply studied and analyzed. 3 the section 鈪，

本文編號(hào)：2321009