为研究竹网在软土地基表层处理中的作用、受力和变形规律,通过实验确定实验材料参数并设计使用液压千斤顶加载的竹网加固软基的室内模型荷载实验,研究载荷作用下竹网的变形和受力特性.实验结果表明:毛竹单杆简支梁在集中荷载作用下的破坏形式为纵向开裂或弯折,弯曲比例极限为6.6~107.2 MPa,极限强度为71.9~117.8 MPa,弹性模量11.59~19.57 GPa;间距为15 cm×15 cm的对边简支竹网的承载能力是单根竹竿的3.7~5.9倍;随着上覆土层厚度的增加,地基压力明显增加,当厚宽比在0~0.69时,对应沉降40 mm的地基压力与软土地基的压力比为2.66~6.96;竹网上应变和应力由于砂土层的扩散作用而降低.
In order to study the effect, stress and deformation of bamboo net in surface treatment of soft soil foundation, the experimental material parameters were determined through experiments, and the indoor model load test of bamboo net reinforced soft foundation with hydraulic jack was designed to study the deformation and stress characteristics of bamboo net under load. The test results show that the failure mode of bamboo single pole simply supported beam under concentrated load is longitudinal cracking or bending, the bending ratio limit is 6.6—107.2 MPa, the ultimate strength is 71.9—117.8 MPa, and the elastic modulus is 11.59—19.57 GPa. The bearing capacity of bamboo net with a spacing of 15 cm×15 cm is 3.7—5.9 times that of a single bamboo rod. With the increase of the thickness of the overlying soil layer, the foundation pressure increases obviously, and when the thickness width ratio is 0—0.69, the foundation pressure over that of soft soil foudation with a corresponding settlement of 40 mm is 2.66—6.96. The strain and stress of bamboo net decrease due to the diffusion of sandy soil layer.
[1] KHOSROW G. Bamboo as reinforcement in structural concrete elements[J]. Cement & Concrete Composites. 2005, 27: 637-649. DOI:org/10.1016/j.cemconcomp.2004.06.002.
[2] 毛筱霏,胡富利.夯筑遗址加固中楠竹锚杆应力分布变化规律研究[J]. 应用力学学报. 2021, 38(1): 345-353.DOI:10.11776/cjam.38.01.B144.
[3] AAZOKHI W. Bamboo reinforcement in shallow foundation on the peat soil[J]. Journal of Civil Engineering Research, 2014, 4(3A): 96-102. DOI:10.5923/c.jce.201402.16.
[4] HEGDE A, SITHARAM T G. Experimental and analytical studies on soft clay beds reinforced with bamboo cells and geocells[J]. International Journal of Geosynthetics and Ground Engineering, 2015, 1(2): 1-13. DOI:10.1007/s40891-015-0015-5.
[5] ASADUZZAMAN M,MUHAMMAD I I. Soil improvement by using bamboo reinforcement[J]. American Journal of Engineering Research, 2014, 3(8):362-368.
[6] WARUWU A, HALIM H. Bamboo grid reinforcement on peat soil under repeated loading[J]. Journal of Engineering and Applied Sciences, 2018, 13(8): 2190-2196. DOI:10.36478/jeasci.2018.2190.2196.
[7] 邓友生,程志和. 竹材结构的抗压试验研究[J]. 科学技术与工程, 2018, 18(27): 223-227.
[8] 祝明桥,张紫薇,王华,等. 竹材力学性能及混凝土环境中影响[J]. 湖南科技大学学报(自然科学版), 2020, 35(3): 50-56. DOI:10.13582/j.cnki.1672-9102.2020.03.008.
[9] 黄松涛. 超软土地基加固现场常见问题及处理对策[J]. 水运工程, 2008(10): 176-182. DOI:10.16233/j.cnki.issn1002-4972.2008.10.028.
[10] 邹光汉. 竹网-土工布处治软基[J]. 国外公路, 1999, 19(4): 54-56. DOI:10.14048/j.issn.1671-2579.1999.04.013.
[11] 孙亮富,张孟喜,林永亮,等. 单向网格状带齿加筋砂垫层加固道路软基的变形特性研究[J]. 土木工学报, 2011, 44(S2): 13-17. DOI:10.15951/j.tmgcxb.2011.s2.023.
[12] 陈楚南,许进明. 竹网在超软基工程淤泥表层处理中的应用[J]. 水运工程, 2007(10): 75-77. DOI:10.16233/j.cnki.issn1002-4972.2007.10.019. (
