本文關(guān)鍵詞： 地基基礎(chǔ)工程 土釘支護(hù) 降雨入滲 土釘軸力 穩(wěn)定性 數(shù)值模擬　出處：《鄭州大學(xué)》2013年碩士論文　論文類型：學(xué)位論文

【摘要】：自上世紀(jì)90年代以來,隨著城市建設(shè)的不斷發(fā)展,建筑趨向高層化,地下空間開發(fā)利用的需求量越來越大,相應(yīng)地基坑工程數(shù)量增多。對于工程地質(zhì)條件相對復(fù)雜的地方,基坑開挖施工過程中安全性問題越來越多,特別是降雨、震動(dòng)等誘發(fā)因素對基坑的穩(wěn)定性有很大不利影響。 土釘支護(hù)體系以其構(gòu)造簡單、施工快捷可靠且工期較短、經(jīng)濟(jì)性好等優(yōu)點(diǎn),在我國基坑圍護(hù)、邊坡支護(hù)、隧道圍巖支護(hù)方面得到了快速推廣和應(yīng)用。但工程實(shí)踐中,土釘支護(hù)體系的失穩(wěn)破壞事故時(shí)常發(fā)生,特別是雨季施工過程中,降雨入滲導(dǎo)致的失穩(wěn)破壞成為土釘支護(hù)體系失效的主要原因之一。本文在總結(jié)前人相關(guān)研究基礎(chǔ)上,采用理論分析和數(shù)值模擬方法,對不同降雨入滲條件下土釘支護(hù)基坑工程的穩(wěn)定性進(jìn)行了研究,得到了一些研究成果： (1)在入滲深度和寬度一定的情況下,隨著入滲位置從開挖面向遠(yuǎn)離開挖面方向移動(dòng),基坑水平位移和沉降先逐漸增大,隨后逐漸減小,在入滲范圍內(nèi)基坑沉降有突增,基坑穩(wěn)定安全系數(shù)隨著入滲位置移動(dòng),先逐漸減小,然后逐漸增大,在土釘長度末端入滲時(shí),達(dá)到峰值,土釘支護(hù)穩(wěn)定性最低。 (2)在入滲深度和位置一定的情況下,隨著降雨入滲寬度的增加,基坑水平位移和沉降逐漸增大,入滲范圍之外土釘軸力相應(yīng)逐漸增大,基坑穩(wěn)定安全系數(shù)逐漸減小。 (3)在入滲寬度和位置一定的情況下,隨著降雨入滲深度的增大,基坑水平位移和沉降也逐漸增大,入滲范圍外土釘軸力也逐漸增大,但當(dāng)入滲達(dá)到一定深度時(shí),基坑水平位移和沉降基本保持穩(wěn)定,隨著入滲深度的繼續(xù)增加,基本保持不變,基坑穩(wěn)定安全系數(shù)隨著入滲深度的增大而減小。 (4)在入滲寬度、深度和位置一定的情況下,隨著降雨導(dǎo)致的土體強(qiáng)度衰減程度的增大,基坑水平位移和沉降逐漸增大,入滲范圍外的土釘軸力也相應(yīng)增大,基坑穩(wěn)定安全系數(shù)逐漸減小。
[Abstract]:Since the last century since 90s, with the continuous development of city construction, the construction tends to be high, the development and utilization of underground space demand is growing, the number of the corresponding foundation pit increased. For relatively complicated engineering geological conditions, more and more security problems in the construction process of foundation pit excavation, especially rainfall, have great adverse effects the stability of vibration induced factors of foundation pit.
Soil nailing system with simple structure, convenient construction and reliable short duration, economical and good in our country, bracing of foundation pit, slope support, tunnel has been rapid promotion and application. But in engineering practice, soil nailing system failure accidents often occur, especially the rainy season in the construction process, rainfall infiltration failure becomes one of the main causes of soil nailing failure caused loss. Based on the summary of previous research on the basis of the theoretical analysis and numerical simulation of different rainfall infiltration in soil nailing bracing of foundation pit stability were studied, and obtained some research results:
(1) the infiltration depth and width is certain, with the infiltration from the excavation location oriented away from the excavation surface direction, and the settlement of foundation pit horizontal displacement increases first, then decreases gradually, the infiltration within the scope of foundation settlement has suddenly increased, the stability of foundation pit safety coefficient with infiltration move gradually decreases, then increases gradually, reached a peak at the end of the infiltration length of soil nailing, and the stability of soil nailing is lowest.
(2)鍦ㄥ叆娓楁繁搴﹀拰浣嶇疆涓，

本文編號(hào)：1505611