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姓名 林貽謙(Yi-Chian Lin) 查詢紙本館藏 畢業系所 土木工程學系 論文名稱 自承式鋼軌樁擋土系統之離心模擬 相關論文 檔案 [Endnote RIS 格式]
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摘要(中) 摘 要
國內外的開挖工程，大都採用連續壁作為擋土設施，隨著挖土作業的逐漸進行，圍苓及水平支撐逐層施作，以達到擋土的目的。但是如果進行大面積的開挖，則水平支撐的架設顯得無效率，而且挖土作業及後續的地下結構物的構築也不方便。因此工程界逐漸於較堅硬的土層中發展出雙排樁無支撐開挖工法。
本研究利用離心模型試驗，藉由模擬開挖過程，探討於砂土層中以自承式單排或雙排鋼軌樁擋土系統作為擋土設施時，不同的開挖與貫入深度比對擋土系統及鄰近地盤之影響。
研究結果顯示，砂土層中以自承式單排或雙排鋼軌樁擋土系統作為擋土設施時，開挖所引致之地表沉陷槽皆屬於三角槽型，影響範圍皆為鋼軌樁擋土壁壁後1.1倍樁長之遠，而壁後最大地表沉陷量可利用樁頂水平變位求得。然而在相同的開挖貫入比之下，使用雙排樁擋土系統之樁頂水平變位、壁後最大地表沉陷量與鋼軌樁樁身所產生之彎矩與剪力確實會比單排樁小；因此，使用雙排鋼軌樁將能大幅提升擋土系統之穩定性。研究結果亦指出，當開挖進行時，雙排樁之前後排樁會透過頂繫樑的束制而產生互拉的作用，進而影響彎矩與剪力的分佈；另外，將雙排鋼軌樁擋土系統視為一重力式擋土牆來進行穩定分析為一可行之方法。摘要(英) ABSTRACT
Diaphragm walls are frequently adopted as soil retaining systems for excavation. However, it is inefficient to excavate in a vast area by using horizontal struts and it is not convenient to do the underground construction work afterward. As a consequence, a double-wall retaining system was developed and used for excavation in a good ground condition.
In this research, centrifuge modeling tests were adopted to simulate the process of excavation to investigate the effects upon adjacent area in various excavation depths and penetration depths by using a single-rail pile wall or a double-rail pile wall as retaining systems.
The results show that the shape of the ground settlement induced by excavation in this study was a triangular one, when a single-rail pile wall or a double-rail pile wall was selected to be the retaining system in sandy layer. The extent of affected area was 1.1 times the pile length behind the wall. Furthermore, the maximum surface settlement can be calculated from the horizontal deformation of the top of pile. Nevertheless, in the same excavation/penetration depth ratio, the horizontal displacement on the top of pile and the maximum surface settlement induced by the single-rail pile wall system were larger than those induced by the double-rail pile wall retaining system. Moreover, the moment and shear force which occurred in the double-rail pile wall system were also less than those in the single-rail pile wall system. Therefore, it would be more stable if the double-rail piles were used as a retaining system. The research also indicated that the front piles and the rear piles would interact with each other during excavation due to the constraint of the cap beam and the distribution of moment and shear force is quite different. According to the research, it may be suitable to assess the stability of the double-rail pile wall system by treating it as a gravity type retaining wall.關鍵字(中) ★ 雙排樁
★ 鋼軌樁
★ 開挖
★ 地盤變位關鍵字(英) ★ Double-rail pile wall
★ Soldier pile
★ Excavation
★ Ground deformation論文目次 目 錄
中 文 摘 要.............................................................................Ⅰ
英 文 摘 要.............................................................................Ⅱ
目 錄.........................................................................................Ⅲ
表 目 錄...................................................................................Ⅴ
圖 目 錄...................................................................................Ⅵ
照 片 目 錄.............................................................................Ⅸ
符 號 說 明.............................................................................Ⅹ
第一章 緒論.............................................................................1
1-1 緣起...........................................................................................1
1-2 研究動機及目的.......................................................................2
1-3 研究架構...................................................................................2
1-4 論文內容...................................................................................3
第二章 文獻回顧.....................................................................5
2-1 懸臂式擋土壁分析...................................................................5
2-2 現場觀測分析...........................................................................7
2-3 數值分析方法.........................................................................10
2-4 物理模型試驗.........................................................................12
2-4-1 1g下之物理模型試驗..............................................................12
2-4-2 離心模型試驗...........................................................................12
2-5 離心模型原理.........................................................................17
2-5-1 離心模型之基本相似律...........................................................18
2-5-2 離心模型試驗之模型模擬.......................................................20
第三章 試驗土樣、儀器設備及試驗方法............................43
3-1 試驗土樣.................................................................................43
3-2 試驗儀器及相關設備.............................................................43
3-2-1 地工離心機...............................................................................43
3-2-2 模型試驗箱...............................................................................44
3-2-3 移動式霣降機...........................................................................45
3-2-4 模型鋼軌樁檔土系統...............................................................47
3-2-5 開挖模擬系統...........................................................................48
3-2-6 相關量測儀器...........................................................................49
3-3 砂試體準備與試驗步驟.........................................................50
3-3-1 試體準備...................................................................................50
3-3-2 離心模型試驗...........................................................................51
第四章 試驗結果與分析.......................................................71
4-1 試驗種類.................................................................................71
4-2 鋼軌樁樁身彎矩分佈.............................................................72
4-2-1 單排鋼軌樁之彎矩分佈............................................................72
4-2-2 雙排鋼軌樁之彎矩分佈............................................................73
4-3 鋼軌樁樁頂水平變位與地表沉陷.........................................75
4-3-1 鋼軌樁樁頂水平變位...............................................................75
4-3-2 地表沉陷型態...........................................................................76
4-3-3 地表沉陷槽分佈範圍...............................................................78
4-4 重覆性試驗之比較.................................................................79
4-5 鋼軌樁樁體變形分析.............................................................80
4-6 鋼軌樁樁體剪力與地盤反力分析.........................................81
4-6-1 樁身所承受之剪力...................................................................82
4-6-2 地盤反力分析...........................................................................84
4-7 自承式鋼軌樁擋土系統穩定分析.........................................86
4-7-1 單排鋼軌樁擋土系統...............................................................86
4-7-2 雙排鋼軌樁擋土系統...............................................................88
第五章 結論與建議.............................................................121
5-1 結論.......................................................................................121
5-2 建議.......................................................................................123
參考文獻.................................................................................125
表 目 錄
表2-1 離心模型試驗與數值模擬之比較 (Zhang and Zhang, 1994)..................23
表2-2 試驗條件 (Kimura et al., 1994).................................................................23
表2-3 原型與離心模型其主要物理量與相似性比較 (李崇正，1994).................24
表3-1 試驗土樣之基本物理性質............................................................................52
表3-2 中央大學地工離心機基本規格 (Acutronic, 1995)....................................53
表3-3 鋼軌樁模型與原型之基本尺寸....................................................................54
表4-1 試驗類別........................................................................................................91
表4-2 各試驗之樁頂水平變位、旋轉角與最大地表沉陷量..................................91
表4-3 前後排樁所受之軸力....................................................................................92
表4-4 單排鋼軌樁之穩定分析................................................................................92
表4-5 雙排鋼軌樁之穩定分析................................................................................92
圖 目 錄
圖2-1 自由端支撐法................................................................................................25
圖2-2 固定端支撐法................................................................................................25
圖2-3 Peck法估計地表沉陷....................................................................................26
圖2-4 Clough and O’Rourke法估計地表沉陷........................................................26
圖2-5 三角槽型地表沉陷剖面預測圖 (歐章煜，2002).........................................27
圖2-6 凹槽型地表沉陷剖面預測圖 (歐章煜，2002).............................................27
圖2-7 最大地表沉陷量與最大擋土壁側向位移量之關係圖 (歐章煜，2002).....28
圖2-8 VERT擋土牆拌合樁配置圖 (Briaud et al., 2000).......................................28
圖2-9 雙排鋼板樁開挖擋土設施圖 (陳厚銘，1999).............................................29
圖2-10 雙排鋼版樁變形示意圖 (陳厚銘，1999)...................................................29
圖2-11 深開挖問題的簡化模式..............................................................................30
圖2-12 winkler樑模式.............................................................................................30
圖2-13 連續體模式..................................................................................................30
圖2-14 兵樁牆後側向土壓力的分佈 (Vermeer et al., 2001).................................31
圖2-15 兵樁牆後主應力的分佈 (Vermeer et al., 2001).........................................31
圖2-16 試驗配置 (Georgiadis and Anagnostopoulos, 1999)..................................32
圖2-17 未支撐開挖試驗配置圖 (陳志豪，2003)...................................................32
圖2-18 氯化鋅模擬土壤重量試驗配置圖 (Bolton and Powrie, 1987).................33
圖2-19 機器手臂開挖試驗配置圖 (Kimura et al., 1994)......................................33
圖2-20 半斷面模型 (Zhang and Zhang, 1994)......................................................34
圖2-21 全斷面模型 (Zhang and Zhang, 1994).......................................................34
圖2-22 沉陷量與隆起量之關係圖 (Zhang and Zhang, 1994)...............................35
圖2-23 邊坡穩定模型 (Zhang and Zhang, 1994)...................................................35
圖2-24 各種方法之比較 (Zhang and Zhang, 1994)...............................................36
圖2-25 未支撐開挖之破壞型態 (Liu, 2002)..........................................................36
圖2-26 支撐開挖之破壞型態 (Liu, 2002)..............................................................37
圖2-27 貫入深度不足之破壞機制 (Bolton and Powrie, 1987).............................37
圖2-28 試驗配置圖 (Leung et al., 2000)................................................................38
圖2-29 擋土壁頂部之變位及轉角與開挖深度之關係圖 (Leung et al., 2000)....38
圖2-30 試驗配置圖 (Leung et al., 2003)................................................................39
圖2-31 開挖過程之沈陷量變化 (Kimura et al., 1994)..........................................39
圖2-32 試驗配置圖 (Khan et al., 2001)..................................................................40
圖2-33 隧道原型與1/N縮尺之離心模型分別在1g及Ng離心力場及有效覆土應力之示意圖..............................................................................................40
圖2-34 1/N縮尺之離心模型座標系統....................................................................41
圖2-35 A’元素在局部座標之加速度分量示意圖..................................................41
圖2-36 模型模擬之觀念..........................................................................................42
圖3-1 試驗土樣之粒徑分布曲線............................................................................55
圖3-2 中央大學地工離心機側視圖 (Acutronic, 1995).........................................56
圖3-3 中央大學地工離心機上視圖 (Acutronic, 1995).........................................57
圖3-4 中央大學地工離心機控制與資料擷取系統示意圖....................................58
圖3-5 模型試驗箱立體分解圖 (陳思宏，1996).....................................................59
圖3-6 移動式霣降機 (陳泓文，1998).....................................................................60
圖3-7 二維滑動架....................................................................................................60
圖3-8 不同鋼管直徑(d)下的相對密度(Dr)與霣降高度(h)之關係圖......................61
圖3-9 不同霣降高度(h)下的相對密度(Dr)與鋼管直徑(d)之關係圖......................61
圖3-10 砂試體之霣降路徑示意圖..........................................................................62
圖3-11 模型鋼軌樁應變計配置圖..........................................................................62
圖3-12 模型鋼軌樁以簡支樑校正示意圖..............................................................63
圖3-13 量測樁頂水平變位示意圖..........................................................................63
圖3-14 PDCR81型迷你孔隙水壓計幾何構造圖 (陳思宏，1996).......................64
圖3-15 迷你孔隙水壓計之包覆層..........................................................................64
圖3-16 鋼軌樁擋土系統試驗配置圖......................................................................65
圖4-1-(a) 雙排鋼軌樁擋土系統..............................................................................93
圖4-1-(b) 符號系統之定義......................................................................................93
圖4-2 STest1鋼軌樁樁身彎矩分佈.........................................................................94
圖4-3 STest2鋼軌樁樁身彎矩分佈.........................................................................94
圖4-4 STest3鋼軌樁樁身彎矩分佈.........................................................................95
圖4-5 STest4鋼軌樁樁身彎矩分佈.........................................................................95
圖4-6 單排鋼軌樁試驗樁身彎矩分佈......................................................................96
圖4-7 STest1與DTest1鋼軌樁樁身彎矩分佈........................................................96
圖4-8 STest2與DTest2鋼軌樁樁身彎矩分佈........................................................97
圖4-9 STest3與DTest3鋼軌樁樁身彎矩分佈........................................................97
圖4-10 STest4與DTest4鋼軌樁樁身彎矩分佈......................................................98
圖4-11 前排鋼軌樁樁身彎矩分佈..........................................................................98
圖4-12 後排鋼軌樁樁身彎矩分佈..........................................................................99
圖4-13 STest1～STest4樁頂水平變位與開挖貫入比之關係圖............................99
圖4-14 DTest1～DTest5樁頂水平變位與開挖貫入比之關係圖.........................100
圖4-15 STest1～STest4樁頂水平變位與開挖深度關係圖..................................100
圖4-16 DTest1～DTest5樁頂水平變位與開挖深度關係圖.................................101
圖4-17 STest1～STest4地表沉陷槽分佈圖..........................................................101
圖4-18 DTest1～DTest5地表沉陷槽分佈圖.........................................................102
圖4-19 最大地表沉陷量與開挖貫入比之關係圖................................................102
圖4-20 最大地表沉陷量與樁頂水平位移關係圖................................................103
圖4-21 各種預測地表沉陷的方法與STest1結果的比較....................................103
圖4-22 各種預測地表沉陷的方法與STest2結果的比較....................................104
圖4-23 各種預測地表沉陷的方法與STest3結果的比較....................................104
圖4-24 各種預測地表沉陷的方法與STest4結果的比較....................................105
圖4-25 各種預測地表沉陷的方法與DTest1結果的比較....................................105
圖4-26 各種預測地表沉陷的方法與DTest2結果的比較....................................106
圖4-27 各種預測地表沉陷的方法與DTest3結果的比較....................................106
圖4-28 各種預測地表沉陷的方法與DTest4結果的比較....................................107
圖4-29 各種預測地表沉陷的方法與DTest5結果的比較....................................107
圖4-30 單排樁開挖引致沉陷影響範圍................................................................108
圖4-31 雙排樁開挖引致沉陷影響範圍................................................................108
圖4-32 STest2與STest5鋼軌樁樁身彎矩分佈....................................................109
圖4-33 STest2與STest5地表沉陷槽分佈圖........................................................109
圖4-34 單排樁樁體位移圖....................................................................................110
圖4-35 前排樁樁體位移圖....................................................................................110
圖4-36 後排樁樁體位移圖....................................................................................111
圖4-37 單排樁之樁體剪力分佈圖........................................................................111
圖4-38 STest2與DTest2之樁體剪力分佈圖........................................................112
圖4-39 STest3與DTest3之樁體剪力分佈圖........................................................112
圖4-40 STest4與DTest4之樁體剪力分佈圖........................................................113
圖4-41 DTest2之前後排樁體剪力相加分佈圖....................................................113
圖4-42 DTest3之前後排樁體剪力相加分佈圖....................................................114
圖4-43 DTest4之前後排樁體剪力相加分佈圖....................................................114
圖4-44 樁頂自由體圖............................................................................................115
圖4-45 單排樁試驗之土壤反力圖........................................................................115
圖4-46 STest2與DTest2之土壤反力圖................................................................116
圖4-47 STest3與DTest3之土壤反力圖................................................................116
圖4-48 STest4與DTest4之土壤反力圖................................................................117
圖4-49 DTest2之前後排土壤反力相加圖............................................................117
圖4-50 DTest3之前後排土壤反力相加圖............................................................118
圖4-51 DTest4之前後排土壤反力相加圖............................................................118
圖4-52 單排樁穩定分析........................................................................................119
圖4-53 雙排樁穩定分析........................................................................................119
照 片 目 錄
照片3-1 試驗箱與可升降式推車............................................................................66
照片3-2 模型鋼軌樁................................................................................................66
照片3-3 模型鋼軌樁擋土系統................................................................................67
照片3-4 自行製作之水袋........................................................................................67
照片3-5 氣水轉換瓶................................................................................................68
照片3-6 壓克力塊....................................................................................................68
照片3-7 LVDT及孔隙水壓計.................................................................................69
照片3-8 置入模型鋼軌樁擋土系統........................................................................69
照片3-9 試驗儀器配置圖(a)....................................................................................70
照片3-10 試驗儀器配置圖(b).................................................................................70參考文獻 參考文獻
[1] 王建智、林宏達、吳明峰，「黏土層深開挖引致之地表沉陷」，地工技術雜誌，第七十六期，第51-62頁(1999)。
[2] 王凱民，「黏土層中懸臂式擋土壁開挖行為探討」，碩士論文，國立中央大學土木工程學系，中壢(2004)。
[3] 江國輝，「通隧引致鄰近基樁之荷重傳遞行為」，碩士論文，國立中央大學土木工程學系，中壢(2003)。
[4] 李崇正，林志棟，林俊雄，「大地工程研究者知新工具：離心模型試驗」，岩盤工程研討會論文集，中壢，第649-669頁(1994)。
[5] 林婷媚，「雙排樁無支撐擋土結構壁體變形行為之研究」，碩士論文，國立雲林科技大學營建工程學系，雲林(2003)。
[6] 莊孟翰，「未襯砌隧道壁變形引致地盤下陷分布形態分析」，碩士論文，國立中央大學土木工程學系，中壢(1996)。
[7] 陳思宏，「黏土層中未襯砌隧道之破壞機制」，碩士論文，國立中央大學土木工程學系，中壢(1996)。
[8] 陳厚銘，「自承式雙排鋼版樁工法擋土開挖行為探討」，地工技術雜誌，第七十五期，第41-48頁(1999)。
[9] 陳志豪，「懸臂式擋土牆開挖之離心模型試驗」，碩士論文，國立中央大學土木工程學系，中壢(2003)。
[10] 歐章煜、謝百鉤，「以經驗公式預測台北盆地深開挖引致之地表沉陷」，地工技術雜誌，第五十三期，第5-14頁(1996)。
[11] 歐章煜、謝百鉤、唐雨耕，「深開挖穩定分析與變形分析」，地工技術雜誌，第七十六期，第25-38頁(1999)。
[12] 歐章煜，深開挖工程分析設計與實務，科技圖書，台北(2002)。
[13] 謝百鉤，「黏土層深開挖引致地盤最大位移預測」，中國土木水利工程學刊，第十三卷，第三期，第489-498頁(2001)。
[14] 謝旭昇、石強、林婷媚，「淺論雙排樁無支撐工法」，地工技術雜誌，第九十七期，第5-14頁(2003)。
[15] Acutronic, Geotechnical Centrifuge Model 665-1 Product Description 5933H, France (1993).
[16] Bolton, M. D., and Powrie, W., “The collapse of diaphragm walls retaining clay,” Geotechnique, Vol. 37, No. 3, pp. 335-353 (1987).
[17] Briaud, J. L., Nicholson, P., and Lee, J., “Behavior of full-scale VERT wall in sand,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 126, No. 9, pp. 808-818 (2000).
[18] Clough, G.W., and O’Rourke T. D., “Construction induced movement of insitu walls,” Proceedings Design and performance of earth retainingst structures, ASCE, pp. 439-470 (1990).
[19] Frydman, S., and Baker, R., “Modelling the soil nailing-Excavation process,” centrifuge 94, Rotterdam, pp. 669-674 (1994).
[20] Georgiadis, M., Anagnostopoulos, C., and Saflekou, S., “Centrifuge testing of laterally loaded piles in sand,” Canadian Geotechnical Journal, Vol. 29, pp. 208-216 (1992).
[21] Georgiadis, M., and Anagnostopoulos, C., “Displacement of structures adjacent to cantilever sheet pile walls,” Soil and Foundations, Vol. 39, No. 2, pp. 99-104 (1999).
[22] Hashash, Y. M. A., and Whittle, J. A., “Ground movement prediction for deep excavations in soft clay,” Journal of Geotechnical Engineering, ASCE, Vol. 122, No. 6, pp. 474-486 (1996).
[23] Ilyas, T., Leung, C. F., and Budi, S. S., “Centrifuge model study of laterally loaded pile groups in clay,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 130, No. 3, pp. 274-283 (2004).
[24] Kimura, T., Takemura, J., Hiro-oka, A., Okamura, M., and Park, J., “Excavation in soft clay using an in-flight excavator,” Centrifuge 94, Rotterdam, pp. 649-654 (1994).
[25] Khan, M. R. A., Takemura, J., Fukushima, H., and Kusakabe, O., “Behavior of double sheet pile wall cofferdam on sand observed in centrifuge tests,” International Journal of Physical Modelling in Geotechnics, IJPMG, Vol. 1, No. 4, pp. 1-16 (2001).
[26] Leung, C. F., Chow, Y. K., and Shen, R. F., “Behavior of pile subject to excavation-induced soil movement,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 126, No. 11, pp. 947-954 (2000).
[27] Liu, J., “Centrifugal modeling of multi-braced and unbraced excavation failures,” Physical Modelling in Geotechnics, Canadian, pp. 841-845 (2002).
[28] Leung, C. F., Lim, J. K., Shen, R. F., and Chow, Y. K., “Behavior of pile groups subject to excavation-induced soil movement,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 129, No. 1, pp. 58-65 (2003).
[29] McNamara, A. M., and Taylor, R. N., “Use of heave reducing piles to control ground movements around excavations,” Physical Modelling in Geotechnics, Canadian, pp. 847-852 (2002).
[30] Madabhushi, S. P., and Chandrasekaran, V. S., “Rotation of cantilever sheet pile walls,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 131, No. 2, pp. 202-212 (2005).
[31] Nahas, A. EL., and Takemura, J., “External stability of vertical excavations in soft clay with self-supported DMM walls,” Soil and Foundations, Vol. 42, No. 1, pp. 53-69 (2002).
[32] Nip, D. C. N., and Ng, C. W. W., “Back-analysis of laterally loaded bored piles,” Geotechnical Engineering, ICE, Vol. 158, pp. 63-73 (2005).
[33] Ou, C. Y., and Lai, C. H., “Finite-element analysis of deep excavation in layered sandy and clayey soil deposits,” Canadian Geotechnical Journal, Vol. 31, pp. 204-214 (1994).
[34] Peck, R. B., “Deep Excavation and tunneling in soft ground,” Proc. 7th Int. Conf. On Soil Mech. Found. Eng., State of Art Volume, pp. 225-290 (1969).
[35] Powrie, W., “Limit equilibrium analysis of embedded retaining walls,” Geotechnique, Vol. 46, No. 4, pp. 709-723 (1996).
[36] Poh, T. Y., Goh, A. T. C., and Wong, I. H., “Ground movements associated with wall construction：case histories,” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 127, No. 12, pp. 1061-1069 (2001).
[37] Takemura, J., Kondoh, M., Esaki, T., Kouda, M., and Kusakabe, O., “Centrifuge model tests on double propped wall excavation in soft clay,” Soil and Foundations, Vol. 39, No. 3, pp. 75-87 (1999).
[38] Tsai, J. S., Jou, L. D., and Hsieh, H. S., “A full-scale stability experiment on a diaphragm wall trench,” Canadian Geotechnical Journal, Vol. 37, pp. 379-392 (2000).
[39] Vermeer, P. A., Punlor, A., and Ruse, N., “Arching effects behind a soldier pile wall,” Computer and Geotechnics, Vol. 28, No. 6, pp. 379-396 (2001).
[40] Zhang, S. D., and Zhang, H. D., “Stability of deep excavations in soft clay,” Centrifuge 94, Rotterdam, pp. 643-648 (1994).指導教授 李崇正(Chung-Jung Lee) 審核日期 2006-6-6 推文 plurk
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