【摘要】：我國西南地區(qū)地質條件復雜、地震頻發(fā),特別是部分地區(qū)還屬于高烈度地震區(qū),地震區(qū)隧道工程就必須解決地震條件下隧道穩(wěn)定性的問題。在山區(qū)修建隧道時,受到特殊地形及地質條件、橋隧搭接方式等因素的限制,雙洞隧道的左右洞間距已經不能保證達到規(guī)范的要求,為此修建了較多的淺埋偏壓小凈距隧道。由于此隧道形式在地震下的響應情況還不明確,也少見于文獻報道,故本文利用振動臺試驗研究淺埋偏壓小凈距隧道在地震下的響應規(guī)律,探究其地震響應機理。本文以國家自然科學基金項目“含地下洞室(群)巖石邊坡地震災變行為與抗震性能評價"(編號:51204125)為依托,開展了淺埋偏壓小凈距隧道的大型振動臺試驗,并采用MidasGTS/NX軟件對左右洞隧道在不同方向、不同加速度峰值的汶川波作用下隧道的響應規(guī)律進行了分析。主要研究內容與結論如下:(1)進行大型振動臺模型試驗,得出了在不同方向、不同加速度峰值汶川地震波輸入下淺埋偏壓小凈距隧道模型的加速度與動應變響應規(guī)律,并分析其原因與特性。認為襯砌加速度受地震波的入射方向影響較大,且Z向的影響大于X向,XZ雙向的影響大于單向。左洞隧道的加速度響應大于右洞隧道。左洞隧道的左半部分,由于埋深較淺、接近臨空坡面,且地震波在坡面會產生波場分裂現象,不同類型的波疊加形成復雜的波場,對隧道襯砌的加速度影響較大。右洞隧道的拱頂和拱腳區(qū)域加速度響應較為劇烈,是抗震設防應著重考慮的部位。(2)襯砌應變受地震加速度峰值的影響較大。隧道襯砌在地震作用下承受拉壓循環(huán)荷載,以受拉為主。右洞隧道襯砌的動應變響應大于左洞隧道。右洞隧道由于上覆巖層較厚,在地震作用下,隧道襯砌的拱腳處,拉壓應變變化劇烈,是最危險的區(qū)域。在對襯砌進行配筋時,左洞隧道應采取非對稱配筋,在接近臨空面的部分適當增加配筋率。隧道的拱腳處應配置雙向受力鋼筋,防止拉壓破壞。(3)建立地震作用下淺埋偏壓小凈距隧道的數值計算三維數值模型,得到了在相同工況下隧道的加速度、內力等響應規(guī)律,并通過隧道襯砌的加速度進行對比分析,驗證了數值模型的可靠性。利用數值模型計算了地震作用下隧道橫截面和縱向的軸力、彎矩和剪力值,隧道橫截面的拱腳部位內力值最大,沿隧道的縱向內力值變化不大。
[Abstract]:The geological conditions in southwest China are complicated and the earthquakes occur frequently, especially in some areas, which belong to the high-intensity seismic area. Tunnel engineering in the seismic area must solve the problem of tunnel stability under earthquake conditions. In the construction of tunnels in mountainous areas, due to special terrain and geological conditions, bridge and tunnel overlap mode and other factors, the distance between left and right tunnels of double-hole tunnel can no longer meet the requirements of the code. For this reason, more shallow burying tunnels with small offset and clear spacing have been built. Because the response of this tunnel form under earthquake is not clear, and is seldom reported in the literature, this paper studies the response law of shallow bias pressure and small net distance tunnel under earthquake by shaking table test, and probes into its seismic response mechanism. Based on the project of National Natural Science Foundation, "earthquake disaster behavior and Seismic performance Evaluation of Rock Slope with Underground cavern (Group)" (No.: 51204125), a large-scale shaking table test of a tunnel with shallow partial pressure and small spacing is carried out in this paper. MidasGTS/NX software is used to analyze the response law of the tunnel under the action of Wenchuan wave in different directions and different acceleration peaks. The main research contents and conclusions are as follows: (1) the response law of acceleration and dynamic strain of the tunnel model with small net distance of shallow buried bias under different direction and different acceleration peak value Wenchuan earthquake wave input is obtained by the model test of large shaking table. The causes and characteristics are analyzed. It is considered that the lining acceleration is greatly affected by the incident direction of seismic wave, and the influence of Z direction is greater than that of X direction XZ direction is greater than that of one direction. The acceleration response of the left tunnel is larger than that of the right tunnel. The left half of the left side of the left tunnel is shallow in depth, close to the slope surface, and the seismic wave will produce wave field splitting phenomenon on the slope surface. Different types of wave superposition form complex wave field, which has a great influence on the acceleration of tunnel lining. The acceleration response of the arch roof and arch foot of the right tunnel is more intense, which should be considered in seismic fortification. (2) the lining strain is greatly affected by the peak seismic acceleration. The tunnel lining is subjected to the cyclic load of tension and compression under earthquake action, mainly under tension. The dynamic strain response of right tunnel lining is larger than that of left tunnel. Due to the thick overlying strata in the right tunnel, the tension and compression strain of the arch of the tunnel lining changes sharply under the earthquake, which is the most dangerous area. When lining is reinforced, asymmetric reinforcement should be adopted in the left tunnel, and the reinforcement ratio should be increased appropriately in the part near the empty surface. In order to prevent the damage of tension and compression, the tunnel arch should be equipped with bidirectional steel bar. (3) the numerical model of shallow buried bias small net distance tunnel under earthquake action is established, and the response law of tunnel acceleration and internal force under the same working condition is obtained. The reliability of the numerical model is verified by comparing and analyzing the acceleration of tunnel lining. The axial force, bending moment and shear force of the tunnel cross section and longitudinal are calculated by using the numerical model. The internal force of the arch foot of the tunnel cross section is the largest, but the longitudinal force along the tunnel does not change much.
【學位授予單位】：中南林業(yè)科技大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：U452.28

【相似文獻】

相關期刊論文 前10條

1 劉明高;高文學;張飛進;;小凈距隧道建設的關鍵技術及其應用研究[J];地下空間與工程學報;2005年06期

2 潘雪峰;;小凈距隧道設計與施工淺談[J];山西交通科技;2007年06期

3 田志宇;林國進;;四川小凈距隧道的發(fā)展與技術要點總結[J];現代隧道技術;2012年01期

4 徐靖;付斌;;小凈距隧道施工[J];山西建筑;2012年22期

5 胡澤書;;淺談高速公路小凈距隧道設計和施工方法[J];黑龍江交通科技;2013年05期

6 倪新興;小凈距隧道施工技術[J];西部探礦工程;2002年03期

7 賴德良;金旗山小凈距隧道施工技術探討[J];華東公路;2003年01期

8 林立彬;金旗山小凈距隧道設計要點與施工中的優(yōu)化處理[J];東北公路;2003年02期

9 叢恩偉;公路并行雙洞小凈距隧道施工技術[J];西部探礦工程;2003年11期

10 齊春峰;小凈距隧道施工工藝[J];西部探礦工程;2004年07期

相關會議論文 前10條

1 劉亮;黃明;鐘祖良;梁寧慧;;高速公路小凈距隧道建設關鍵技術分析[A];第十屆全國青年巖石力學與工程學術大會論文集[C];2009年

2 賴錦興;;里洋小凈距隧道設計[A];2001年全國公路隧道學術會議論文集[C];2001年

3 黃波;;小凈距隧道施工技術要點[A];第二屆全國公路科技創(chuàng)新高層論壇論文集（上卷）[C];2004年

4 姚勇;何川;田志宇;;小凈距隧道爆破振動特征及控爆分析[A];城市地下空間開發(fā)與地下工程施工技術高層論壇論文集[C];2004年

5 汪子勇;孟凡良;;小凈距隧道施工[A];全國礦山建設學術會議論文選集（下冊）[C];2004年

6 T3家惠;曾何，

本文編號：2202941