English  |  正體中文  |  简体中文  |  Items with full text/Total items : 52052/87180 (60%)
Visitors : 8895551      Online Users : 151
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version
    Please use this identifier to cite or link to this item: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/111267

    Title: 軟弱地盤中樁筏基礎構造之靜態力學行為
    Other Titles: Static behaviors of piled raft foundations in soft ground sites
    Authors: 林于茹;Lin, Yu-Ru
    Contributors: 淡江大學土木工程學系碩士班
    張德文;Chang, Der-Wen
    Keywords: 樁筏基礎;版式與箱式基礎;靜態分析;參數研究;三維有限元素分析;piled raft foundation;plate raft and cellular raft foundation;static behavior;parametric study;three-dimensional finite element analysis
    Date: 2016
    Issue Date: 2017-08-24 23:48:28 (UTC+8)
    Abstract: 本研究係採三維有限元素程式MIDAS/GTS NX模擬版式與箱式筏樁基礎於垂直向和水平向靜態均佈荷載下之力學行為。樁筏基礎數值模型係位於砂土-黏土-砂土所組合之地層,土壤材料參數及結構參數變化對基礎靜態行為之影響為觀察重點。所選擇的力加載方式包括:1.依時性壓密分析、2.階段施力(排水參數)分析、3.階段施力(不排水參數)分析,其中依時性壓密分析與階段施力(排水參數)分析中,黏土層採用修正劍橋黏土模式進行模擬,砂土層則以莫爾庫倫破壞模式進行模擬;而階段施力(不排水參數)分析中,黏土層與砂土層皆以莫爾庫倫破壞模式進行模擬。透過不同分析,本研究可以了解相關基礎在短期和長期受力情況下的差異性。
    This study intends to discuss the vertical and horizontal load on static behaviors of piled raft foundations using the three-dimensional finite element analyses based on the software MIDAS/GTS NX program. The numerical models respectively with plate raft and cellular raft underlain by a number of piles were considered. Sand-clay-sand sols are assumed for the ground site. Three types of the static analysis were considered which includes: a. Time-dependent consolidation, b. Stage load drained, and c. Stage load undrained condition. In time-dependent consolidation and stage load drained analyses, Mohr Coulomb model and Modified Cam Clay (MCC) model are respectively used for sand and clay. For staged loading undrained case, only Mohr Coulomb model is adopted. The different analyses were aimed to simulate the long-term and short-term foundation behaviors.
    This study finds that: 1.The time-dependent consolidation analysis and the staged loading drained analysis will yield similar long-term results when excess pore pressure fully dissipates. The effects of the influence factors became relatively unimportant for short-term condition. 2. The foundation settlements are in the order where center>edge>corner; loads distributed at the foundation are the opposite. 3. The foundation settlement becomes smaller when cellular raft is encountered. However since pile length is remained, the stresses of piles were increased due bearing sandy layer at bottom of the piles. 4. Soil model and soil parameters in use will affect the results. Elastic constants are more important than strength parameters when Mohr Coulomb model is used. For MCC model, the compressibility parameters are typically important. 5. Thickness of the soil layers, pile length and pile-to-pile spacing ratio (S/D) are the most significant factors; and they are more important in the cases of plate raft. 6. The resistance of sand-clay-sand site is higher than that of a single layer of soft clays. For long-term analysis, vertical and horizontal loads carried by the piles are respectively 55% and 60% of the foundation loads for plate raft, whereas the loading ratios become 34% and 57% in the case of cellular raft. 7. As S/D increased, the loads carried by piles decreased, however the internal stress of piles will be enlarged in which the pile damages could occur 8. For short-term analysis, the loads carried by piles are also found smaller in the case of cellular raft. Since the results are indeed related to site condition, the interpretations should be careful.
    Appears in Collections:[土木工程學系暨研究所] 學位論文

    Files in This Item:

    File Description SizeFormat

    All items in 機構典藏 are protected by copyright, with all rights reserved.

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - Feedback