【正文】
l. (1997) 分析了力學(xué)機(jī)制 和 FLAC 隧道 襯里復(fù)雜的承載能力,得到一些有用的 結(jié)論。 ZHU et al. 1996)。 YAN et 在不同施工 2 方案中支撐的 機(jī)械特性 和 變形規(guī)則。 2 工程概況 工程地質(zhì) 地質(zhì)調(diào)查顯示 ,底部隧道主要打通 的 是下面的基礎(chǔ) , 主要是泥巖,砂巖 。, 結(jié)合層巖石 很普通, 巖石的 等級是五級。地質(zhì)構(gòu)造的表面非常 發(fā)達(dá),巖體 極其支離破碎 ,而且塊強(qiáng)度不夠強(qiáng)。先進(jìn) 小管 的外半徑是 Φ42mm, 長度 是四十厘米 。隧道圍巖被認(rèn)為是彈塑性材料。為確保計(jì)算 的 準(zhǔn)確性該模型維度 可以設(shè)為 :左和右都長 50米垂直于地 球表面下為 50米。后期隧道拱頂端地面沉降量是 。 與一般的大垮較淺深度的隧道地表沉降的現(xiàn)場測量值相比,頂部處理的沉降值略小。在施工過程中應(yīng)該加強(qiáng)現(xiàn)場監(jiān)測的力度。符合螺栓軸向力在柔弱巖石上的分布格局。 先進(jìn)的小管的支持、初期支護(hù) ,其次 內(nèi) 襯可以預(yù)防 塑性區(qū) 進(jìn)一步擴(kuò)張 ,塑性區(qū)深度 ,不會(huì)超過一半 的 隧道寬度 ,而在允許范圍內(nèi)。 對 上述結(jié)果進(jìn)行分析地面沉降、隧道周邊的垂直位移 ,支撐的承載力和 塑性區(qū) 雙邊墻建設(shè)方案 是合理的。 ) 力學(xué)模擬及軟弱巖石中的行為分析 , 興建一條隧道開放。 【 巖石和土壤力學(xué) 】 ( 3, 193200) 模擬三維隧道挖掘。 ( 2020 年) 。 肖明( 2020年)。 【高速 公路 】 ( 7, 5558) 討論環(huán)境對小間距研究 長 隧道 的影響。 【 中國巖石 工程 力學(xué) 】 ( 3, 572577) 對軟巖 施工 特性 和 動(dòng)態(tài) 行為 的研究 。 劉 紅州, 陳三佳( 2020 年) 圖 1 有限元分析模型 5 圖 2 地表沉陷圖表 圖 3 圍巖的垂直位移( mm) 圖 4 主要支撐的等量壓力 圖 5 螺栓的軸力圖 圖 6 次連接的等量應(yīng)力 圖 7 圍巖的塑性區(qū) Study on Dynamic Construction Mechanics of SmallDistance Tunnel in Soft and Weak Rocks Hengbin Wu (Corresponding author) Department of Civil Engineering, Chongqing Three Gorge University 780 Erduan Shalong Road, Wanzhou District, Chongqing 404000, China Email: Yunxiang He Department of Civil Engineering, Chongqing Three Gorge University 780 Erduan Shalong Road, Wanzhou District, Chongqing 404000, China Guoliang Song Liaocheng Jianyu Construction Engineering Co.,Ltd Liaocheng 252020, China Abstract 6 Based on the construction theory of New Austria Method(NAM), relyed on a tunnel project of small distance in soft and weak rocks, this paper builds the numerical model and simulates 3D finite element method elastoplastic of the construction process by the construction method of doublesidewalls. The displacement changes of some points around the tunnel are analysised with the tunnel’s excavation. The safety of the tunnel structure and stability of surrounding rock are estimated by analyzing the surface subsidence, forces undertaken by the supporting structures and plastic zone. The results show that the method of construction mentioned above is reasonable, the influence of the later tunnel excavation on the surface subsidence and tunnel deformations of the earlier tunnel excavation is relatively obvious. Keywords: Soft and weak rocks, Small distance tunnel, Dynamic construction mechanics, Numerical simulation 1. Introduction The excavation and supporting process of tunnel is a plicated mechanical process, the differences of construction process, excavation sequence and supporting time greatly influence on the mechanics effects of engineering structure systematic(SHE et al., 2020). Because of the plexity of the condition of surrounding rock, the ordinary analogy of projects is not enough in the plex lining in soft and weak rocks especially in the tunnel engineering with small distance, so it’s necessary to conduct the mechanical simulating and analyzing in different surrounding rock characters according to the different forcing stages in each load case during construction processes. In the aspect of the research on the tunnel lining in soft and weak rocks, SUN et al. (1994) builded the three dimension model considering the timespace effect of tunnel excavating surface. CHENG et al. (1997) analyzed the mechanical mechanism and carrying capacity of plex lining for tunnels with FLAC, and got some useful conclusions. JIN et al. (1996) conducted three dimension FEM (finite element method) numerical simulation to the excavation processes of circle tunnel using the nonlinear viscoelastic theory. Karakus(2020)elaborated three dimension excavating effect caused by plane strain analyses. Because the timespace effect could not be fu