研究生: |
李俊葦 Chun-wei Lee |
---|---|
論文名稱: |
利用三軸無圍試驗探討纖維與水泥對粉土剪力強度與纖維握裹力的影響 Unconfined compression test on Fiber-Reinforced Cemented Silt: Effect of Cement on Fiber Bonding Strength |
指導教授: |
楊國鑫
Kuo-Hsin Yang |
口試委員: |
劉家男
Chia-Nan LIU 廖敏志 Min-Chih Liao |
學位類別: |
碩士 Master |
系所名稱: |
工程學院 - 營建工程系 Department of Civil and Construction Engineering |
論文出版年: | 2016 |
畢業學年度: | 104 |
語文別: | 中文 |
論文頁數: | 118 |
中文關鍵詞: | 無圍壓縮試驗 、加勁纖維 、電子顯微鏡 、低滲透性土壤 |
外文關鍵詞: | Unconfined Compression Test, Fiber-reinforced, Silt, Scanning Electron Microscopy |
相關次數: | 點閱:187 下載:6 |
分享至: |
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
加勁纖維土壤為在土壤中添加人造或者天然纖維拌合,藉以提升土壤剪力強度及整體穩定性,可以應用在修復局部邊坡破壞,提升邊坡穩定性與坡面抗沖蝕性。本研究探討纖維與水泥對低滲透性土壤不排水剪力強度之影響。本研究以三軸無圍壓縮試驗求取粉土添加纖維與水泥後的無圍壓縮強度。此外,本研究亦利用電子顯微鏡觀察纖維、土壤與水泥顆粒的互制行為,進而驗證添加水泥對纖維握裹力的影響。本研究試驗變因包括纖維含量、纖維長度、水泥含量。試驗結果顯示,當加勁纖維含量提升,其無圍壓縮強度提升但勁度下降,試體破壞模式由原本脆性轉為韌性;而纖維長度提升對於強度影響較不明顯。此外,水泥的添加使強度以及勁度皆大幅提升,隨著纖維含量增加勁度逐漸下降,但仍大於純粉土之勁度。水泥加勁試體之破壞模式也隨纖維含量加,其破壞模式也由脆性轉為韌性。本研究探討添加水泥與纖維造成土壤強度提升增加之原因,研究發現除了纖維以及水泥自身對強度增加的貢獻外,添加水泥後,纖維將獲得額外握裹力造成更有效的土壤-纖維互制機制,故強度大幅提升。最後,在後續工程應用上,依據本研究結果,在加勁纖維土壤內添加微量之水泥能有效增加加勁纖維土壤的勁度與強度,進而提升整體地工構造物之穩定性。
Marginal soils (i.e., silt and clay) have not been a preferred option of a backfill material for reinforced soil structures due to its low shear strength and permeability. In this research, fiber-reinforced silt (FRS) and fiber-reinforced cemented silt (FCS) were studied as a measure of improving the stability of reinforced soil structures backfilled with marginal soil. A series of triaxial unconfined compression tests are perform to investigate the effect of adding polypropylene (PP) fibers and cement on the shear behavior and failure mode of silty soil subject to undrained loadings. The test variables considered in this study are fiber content (0, 1, 2, 3%), fiber length (6, 12, 19 mm) and cement content (0, 5%). The specimens were prepared at a maximum dry unit weight and optimum moisture content based on standard proctor compaction test results. For FCS specimens, the 7 day curing strength was obtained and compared in this study. The experimental results revealed that adding fiber and cement substantially increased the undrained shear strength and reduced the loss of post peak strength of the reinforced soil. The failure mode steadily transformed from brittle to ductile type as the fiber content increased. Test results also indicated that the modulus of FRS under working stress conditions (at 2% of axial strain) decreased as fiber content increased but increased as fiber length increased. Regardless of fiber content and length, the modulus of FRS is less than that of unreinforced silt, whereas the modulus of FCS is larger than that of unreinforced silt. The improvement of undrained shear strength as a result of cement-induced extra boning strength was determined by quantifying the strength increment between FRS and FCS specimens. The analytical results suggested that for reinforced specimens with 2 and 3% of fiber content the strength improvement from the contribution of cement-induced extra boning strength is larger than that from the contribution of fiber alone. This observation demonstrated the significance of adding cement as an adhesive to improve the bonding strength between fiber and soil matrix. As a result, higher fiber tensile strength could be mobilized and contributed to the increase of overall undrained shear strength of reinforced soil. Images acquired from scanning electron microscope (SEM) also provided clear visual evidences of soil-fiber interaction improved by adding cement.
1.ASTM D421, (2007). “Standard Practice for Dry Preparation of Soil Samples for Particle-Size Analysis and Determination of Soil Constants ” Designation: D421-85.
2.ASTM D422, (2007). “Standard Test Method for Dispersive Characteristics of Clay Soil by Double Hydrometer” Designation: D422-63.
3.ASTM D4318, “Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils” Designation: D4318-84.
4.ASTM D698, “Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort” Designation: D698-12e2.
5.ASTM D5084, “Standard Test Methods for Measurement of Hydraulic Conductivity of Saturated Porous Materials Using a Flexible Wall Permeameter” Designation: D5084-10.
6.ASTM D2166, “Standard Test Methods for Unconfined Compressive Strength of Cohesive Soil” Designation: D2166/D2166M − 13.
7.Anagnostopoulos, C. A., Papaliangas, T. T., Konstantinidis, D., & Patronis, C. (2013). Shear Strength of Sands Reinforced with Polypropylene Fibers. Geotechnical and Geological Engineering, 31(2), 401-423.
8.Bouhicha, M., Aouissi, F., & Kenai, S. (2005). Performance of composite soil reinforced with barley straw. Cement and Concrete Composites, 27(5), 617-621.
9.C, C., P, M., M, D., & M, P. (2004). Effect of material properties on the behavior of sand-cement-fiber composites. Ground Improvement, 8(2), 77-90.
10.Chauhan, M. S., Mittal, S., & Mohanty, B. (2008). Performance evaluation of silty sand subgrade reinforced with fly ash and fibre. Geotextiles and Geomembranes, 26(5), 429-435.
11.Choudhary K, J. J., Gill S. (2010). A study on CBR behavior of waste plastic strip reinforced soil. Emirates Journal for Engineering Research, 15, 51-57.
12.Consoli, N. C., Vendruscolo, M. A., Fonini, A., & Rosa, F. D. (2009). Fiber reinforcement effects on sand considering a wide cementation range. Geotextiles and Geomembranes, 27(3), 196-203.
13.Ghavami, K., Toledo Filho, R. D., & Barbosa, N. P. (1999). Behaviour of composite soil reinforced with natural fibres. Cement and Concrete Composites, 21(1), 39-48.
14.Gosavi M, P. A., Mittal S, Saran S. (2004). Improvement of properties of black cotton soil subgrade through synthetic reinforcement. Journal of The Institution of Engineers (India), 84, 257-262.
15.Gray, D., & Ohashi, H. (1983). Mechanics of Fiber Reinforcement in Sand. Journal of Geotechnical Engineering, 109(3), 335-353. doi:10.1061/(ASCE)0733-9410(1983)109:3(335)
16.Hejazi, S. M., Sheikhzadeh, M., Abtahi, S. M., & Zadhoush, A. (2012). A simple review of soil reinforcement by using natural and synthetic fibers. Construction and Building Materials, 30, 100-116.
17.Hossain, M. A., Hossain, M. S., & Hasan, M. K. (2015). Application of Jute Fiber for the Improvement of Subgrade Characteristics. American Journal of Civil Engineering, 3(2), 26-30.
18.Ibraim, E., & Fourmont, S. (2007). Behaviour of Sand Reinforced with Fibres. In H. I. Ling, L. Callisto, D. Leshchinsky, & J. Koseki (Eds.), Soil Stress-Strain Behavior: Measurement, Modeling and Analysis: A Collection of Papers of the Geotechnical Symposium in Rome, March 16–17, 2006 (pp. 807-818). Dordrecht: Springer Netherlands.
19.Kaniraj, S., & Havanagi, V. (2001). Behavior of Cement-Stabilized Fiber-Reinforced Fly Ash-Soil Mixtures. Journal of Geotechnical and Geoenvironmental Engineering, 127(7), 574-584. doi:10.1061/(ASCE)1090-0241(2001)127:7(574)
20.Kim, Y. T., Kim, H. J., & Lee, G. H. (2008). Mechanical behavior of lightweight soil reinforced with waste fishing net. Geotextiles and Geomembranes, 26(6), 512-518.
21.Kumar, A., Walia, B. S., & Mohan, J. (2006). Compressive strength of fiber reinforced highly compressible clay. Construction and Building Materials, 20(10), 1063-1068.
22.Kumar S, T. E. (2003). Strength characteristics of silty clay reinforced with randomly oriented nylon fibers. Electronic Journal of Geotechnical Engineering, 127, 774-782.
23.Li, C. (2005). Mechanical response of fiber-reinforced soil Retrieved fromhttp://repositories.lib.utexas.edu/bitstream/handle/2152/1781/lic25697.pdf
24.Li, J., Tang, C., Wang, D., Pei, X., & Shi, B. (2014). Effect of discrete fibre reinforcement on soil tensile strength. Journal of Rock Mechanics and Geotechnical Engineering, 6(2), 133-137.
25.Maher, M. H., & Ho, Y. C. (1994). Mechanical Properties of Kaolinite/Fiber Soil Composite. Journal of Geotechnical Engineering, 120(8), 1381-1393.
26.Marandi, S. M., Bagheripour, M. H., Rahgozar, R., & Zare, H. (2008). Strength and Ductility of Randomly Distributed Palm Fibers Reinforced Silty-Sand Soils. American Journal of Applied Sciences, 5(3), 209-220
27.Mirzababaei, M., Miraftab, M., Mohamed, M., & McMahon, P. (2012). Unconfined Compression Strength of Reinforced Clays with Carpet Waste Fibers. Journal of Geotechnical and Geoenvironmental Engineering, 139(3), 483-493.
28.Muntohar, A. S., Widianti, A., Hartono, E., & Diana, W. (2013). Engineering Properties of Silty Soil Stabilized with Lime and Rice Husk Ash and Reinforced with Waste Plastic Fiber. Journal of Materials in Civil Engineering, 25(9), 1260-1270.
29.Nasr, A. M. (2014). Behavior of strip footing on fiber-reinforced cemented sand adjacent to sheet pile wall. Geotextiles and Geomembranes, 42(6), 599-610.
30.Park, S.-S. (2009). Effect of fiber reinforcement and distribution on unconfined compressive strength of fiber-reinforced cemented sand. Geotextiles and Geomembranes, 27(2), 162-166.
31.Prabakar, J., & Sridhar, R. S. (2002). Effect of random inclusion of sisal fibre on strength behaviour of soil. Construction and Building Materials, 16(2), 123-131.
32.Puppala, A. J., & Musenda, C. (2000). Effects of fiber reinforcement on strength and volume change behavior of expansive soils. Transportation Research Record: Journal of the Transportation Research Board, 1736, 134-140.
33.S. M. Marandi, M. H. B., R. Rahgozar and H. Zare. (2008). Strength and Ductility of Randomly Distributed Palm Fibers Reinforced Silty-Sand Soils. American Journal of Applied Sciences, 5(3), 209-220.
34.Sadek, S., Najjar, S., & Freiha, F. (2010). Shear Strength of Fiber-Reinforced Sands. Journal of Geotechnical and Geoenvironmental Engineering, 136(3), 490-499. doi:10.1061/(ASCE)GT.1943-5606.0000235
35.Santoni, R., & Webster, S. (2001). Airfields and Roads Construction Using Fiber Stabilization of Sands. Journal of Transportation Engineering, 127(2), 96-104. doi:10.1061/(ASCE)0733-947X(2001)127:2(96)
36.Segetin, M., Jayaraman, K., & Xu, X. (2007). Harakeke reinforcement of soil–cement building materials: Manufacturability and properties. Building and Environment, 42(8), 3066-3079.
37.Tang, C.-S., Shi, B., & Zhao, L.-Z. (2010). Interfacial shear strength of fiber reinforced soil. Geotextiles and Geomembranes, 28(1), 54-62.
38.Tang, C., Shi, B., Gao, W., Chen, F., & Cai, Y. (2007). Strength and mechanical behavior of short polypropylene fiber reinforced and cement stabilized clayey soil. Geotextiles and Geomembranes, 25(3), 194-202.
39.V., M. (2011). Performance of fiber reinforced clayey soil. Electronic Journal of Geotechnical Engineering, 16, 1067-1087.
40.Yetimoglu, T., Inanir, M., & Esat Inanir, O. (2005). A study on bearing capacity of randomly distributed fiber-reinforced sand fills overlying soft clay. Geotextiles and Geomembranes, 23(2), 174-183.
41.Yetimoglu, T., & Salbas, O. (2003). A study on shear strength of sands reinforced with randomly distributed discrete fibers. Geotextiles and Geomembranes, 21(2), 103-110.
42.Yi, X. W., Ma, G. W., & Fourie, A. (2015). Compressive behaviour of fibre-reinforced cemented paste backfill. Geotextiles and Geomembranes, 43(3), 207-215.
43.Z., J., Z., T., R., K., & N., N. (2010). The effect of oil palm fibre on strength behaviour of soil. Paper presented at the SANREM, Kota Kinabalu, Malaysia.