本文關(guān)鍵詞： 大斷面小凈距隧道 監(jiān)控量測(cè) 參數(shù)反演 數(shù)值模擬 圍巖穩(wěn)定性　出處：《西安科技大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：本文通過(guò)對(duì)隧道施工過(guò)程監(jiān)測(cè)項(xiàng)目進(jìn)行監(jiān)測(cè),然后對(duì)監(jiān)測(cè)所得數(shù)據(jù)進(jìn)行整理和線性回歸分析,找出圍巖在開(kāi)挖支護(hù)后變形的內(nèi)在規(guī)律,反演出隧道洞室圍巖的綜合物理力學(xué)參數(shù),以此來(lái)進(jìn)行隧道施工方案等方面的研究,主要內(nèi)容如下:⑴本文結(jié)合巖石力學(xué)理論計(jì)算方法和現(xiàn)場(chǎng)監(jiān)控量測(cè)的特點(diǎn),立足于隧道典型斷面觀測(cè)點(diǎn)模擬所得數(shù)據(jù),從隧道圍巖的穩(wěn)定性定量評(píng)價(jià)方法著手,進(jìn)行隧道圍巖穩(wěn)定方面的探討。隧道在不同的斷面形式情況下,圍巖應(yīng)力分布不盡相同。隧道斷面形式為五心圓時(shí),其圍巖應(yīng)力狀態(tài)更接近實(shí)際工程中對(duì)隧道結(jié)構(gòu)受力均勻性方面的要求。⑵基于現(xiàn)場(chǎng)監(jiān)控量測(cè)數(shù)據(jù),及時(shí)運(yùn)用圍巖參數(shù)反演程序進(jìn)行分析,可以比較準(zhǔn)確的反演隧道圍巖等效力學(xué)參數(shù),以此能夠快速、準(zhǔn)確地對(duì)隧道施工中圍巖穩(wěn)定性做出合理的評(píng)價(jià),及預(yù)測(cè)未開(kāi)挖段隧道在開(kāi)挖支護(hù)后圍巖的穩(wěn)定性。然后利用參數(shù)反演得出的巖體物理力學(xué)參數(shù)建立三維數(shù)值模型,通過(guò)計(jì)算對(duì)比得出,大斷面小凈距隧道使用三臺(tái)階七步開(kāi)挖法進(jìn)行施工時(shí)相對(duì)于CD工法的施工組織設(shè)計(jì)復(fù)雜,施工速度緩慢等缺點(diǎn),施工成本降低,具有廣泛地推廣價(jià)值以及應(yīng)用前景,在國(guó)內(nèi)同類大斷面小凈距隧道施工方面提供一定的參考依據(jù)。⑶通過(guò)數(shù)值模擬研究了凈距在10m、12m、15m、18m、20m等5種工況下,隧道圍巖典型觀測(cè)點(diǎn)處應(yīng)力應(yīng)變特征等,得出大斷面小凈距隧道在使用三臺(tái)階七步開(kāi)挖法,埋深為30m、圍巖等級(jí)為Ⅴ級(jí)的情況下,和本文地形及地質(zhì)等限制條件相似地段,隧道雙洞凈距選用12~15m的范圍較為合適。⑷通過(guò)數(shù)值模擬研究了掌子面間距為3m、6m、9m、12m、15m共五種工況進(jìn)行數(shù)值模擬,得出當(dāng)施工間距為12m時(shí),隧道圍巖穩(wěn)定性相對(duì)較差,但在安全可控范圍,另外也有利于縮短施工工期。
[Abstract]:In this paper, the monitoring project of tunnel construction process is monitored, and then the monitoring data are sorted out and linear regression analysis is made to find out the inherent law of the deformation of surrounding rock after excavation and support. The comprehensive physical and mechanical parameters of surrounding rock of tunnel chamber are inversely performed to study the tunnel construction scheme. The main contents are as follows: 1 this paper combines the calculation method of rock mechanics theory and the characteristics of on-site monitoring measurement. Based on the simulation data obtained from the observation points of typical section of tunnel, the stability of surrounding rock of tunnel is discussed from the quantitative evaluation method of the stability of surrounding rock of tunnel. The stress distribution of surrounding rock is different. When the cross section of tunnel is five-center circle, the stress state of surrounding rock is closer to the requirement of uniform stress of tunnel structure in actual engineering based on field monitoring data. By using the inversion program of surrounding rock parameters in time, the equivalent mechanical parameters of surrounding rock can be retrieved accurately, so that the stability of surrounding rock in tunnel construction can be evaluated quickly and accurately. And to predict the stability of surrounding rock after excavation and support of unexcavated tunnel. Then the three-dimensional numerical model of rock mass physical and mechanical parameters obtained by parameter inversion is established, and the results are obtained by calculation and comparison. Compared with CD method, the construction organization design is complex, the construction speed is slow and the construction cost is reduced when the three-step and seven-step excavation method is used in large section and small clear distance tunnel, so it has extensive popularization value and application prospect. By numerical simulation, the stress and strain characteristics of tunnel surrounding rock at typical observation point of surrounding rock are studied under 5 conditions, such as 10m ~ 12m ~ 15m ~ 15m ~ 18m ~ 20m, etc., which provide some reference basis for the construction of similar large section and small net distance tunnel in our country, and through numerical simulation, the stress and strain characteristics of tunnel surrounding rock at typical observation points are studied. It is concluded that in the case of large section and small clear distance tunnel excavation with three steps and seven steps, the buried depth is 30m and the surrounding rock grade is grade 鈪，

本文編號(hào)：1494141