大直径超长钻孔灌注桩承载性状

冯忠居; 谢永利; 李哲; 张宏光

大直径超长钻孔灌注桩承载性状

长安大学特殊地区公路工程教育部重点实验室, 陕西西安 710064

基金项目:

国家西部交通建设科技项目 2001 318 000 17

详细信息

作者简介:
冯忠居(1965-), 男, 山西万荣人, 长安大学副教授, 博士, 从事岩土工程研究

中图分类号: U443.15
计量
- 文章访问数: 291
- HTML全文浏览量: 76
- PDF下载量: 621
- 被引次数: 0
出版历程
- 收稿日期: 2004-12-05
- 刊出日期: 2005-03-25

Bearing property of large-diameter over-length nonplacement pile

Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang'an University, Xi'an 710064, China

More Information

Author Bio:
FENG Zhong-ju(1965-), male, PhD, associate professor, 86-29-82336860, zhongjufeng@tom.com

摘要

摘要: 基于芝川河特大桥的桩基原位试验, 对粉质砂土地区大直径超长钻孔灌注桩的承载力性状进行了分析, 并将实测成果与现行《公路桥涵地基与基础设计规范》中经验公式的计算结果进行了对比分析。发现大直径超长钻孔灌注桩的承载力性状和中长桩或短桩的承载力性状具有明显差异; 粉质砂土处于地面以下的不同部位, 其侧阻力有较大差异; 规范公式计算承载力结果明显小于原位试验结果, 相差超过50%。研究结果表明, 相同土质处于地面以下不同部位对桩产生的极限摩阻力不同, 规范公式不适于评价大直径超长桩的承载力。
- 桥梁工程 /
- 大直径超长桩 /
- 承载力 /
- 粉质砂土 /
- 极限侧阻力 /
- 极限端阻力
Abstract: Based on the field test of pile foundation in Zhichuan river bridge, the bearing property of large-diameter over-length nonplacement pile in the area of powder sandy soil was studied, a comparison was made between the test result and the calculation value of empirical formula. It is pointed that there is a remarkable difference between the bearing property of large-diameter over-length nonplacement pile and that of medium length or short ones, when powder sandy soil is in different depth underground, its lateral resistance is different significantly, the bearing capacity difference of experimental piles and normalized formula is over 50%. The results show that the limiting lateral resistances of powder sandy soil of different depth are different, the normalized formula is not suited to evaluate the bearing capacity of large-diameter over-length nonplacement pile.
- bridge engineering /
- large-diameter over-length pile /
- bearing capacity /
- silty sand /
- limiting lateral resistance /
- limiting end resistance

HTML全文

图 1 荷载(Q) 与沉降(S) 分布曲线

Figure 1. Load-settlement curves

下载: 全尺寸图片幻灯片

图 2 桩的轴力分布

Figure 2. Arrangement curves of axial force

下载: 全尺寸图片幻灯片

图 3 桩端阻力分布曲线

Figure 3. Arrangement curve of pile end resistance

下载: 全尺寸图片幻灯片

图 4 桩侧阻力分布曲线

Figure 4. Arrangement curves of side resistance

下载: 全尺寸图片幻灯片

表 1 各级荷载下桩端阻力

Table 1. Pile end resistance under different loads

	荷载等级/MN
	1.6、3.2、4.8、8.0、9.6	11.2	12.8	14.4	16.0	17.6	19.2
桩端荷载/MN	0	0.44	0.88	1.14	1.28	1.62	1.75
端阻占各级荷载百分比/%	0	3.7	6.9	7.9	8.0	9.2	9.1

下载: 导出CSV

表 2 桩侧土层极限侧摩阻力

Table 2. Limiting lateral resistance of side pile soil layers

土层	土名	测试极限摩阻力/kPa	规范值/kPa
1	细砂	90.82	20~80
2	中砂	53.20	55~90
3	卵石	77.09	—
4	细砂	27.44	20~80
5	粉质粘土	49.06	15~95
6	细砂	84.31	20~80
7	粉质粘土	27.55	15~95
8	细砂	83.06	20~80

下载: 导出CSV

表 3 各土层参数取值

Table 3. Parameters of different soil layers

承载力	土名
承载力	细砂	中砂	卵石	粉质粘土
[σ]/kPa	80	300	600	280
[τ]/kPa	30	40	150	40
λ=0.85 m₀=0.90

下载: 导出CSV

参考文献(9)

[1]	冯忠居, 黄安录. 大直径钻孔灌注桩承载力的研究[J]. 工程力学学报, 2000, 17(4): 449-453. https://www.cnki.com.cn/Article/CJFDTOTAL-JCJG200105024.htm FENG Zhong-ju, HUANG An-lu. Study on bearing capacity of large diameter bored piles[J]. Journal of Engineering Mechanics, 2000, 17(4): 449-453. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-JCJG200105024.htm
[2]	冯忠居. 基础工程[M]. 北京: 人民交通出版社, 2001.
[3]	冯忠居, 张永清, 李晋. 堆载引起桥梁墩台与基础的偏移与防治技术研究[J]. 中国公路学报, 2004, 17(3): 74-77. doi: 10.3321/j.issn:1001-7372.2004.03.015 FENG Zhong-ju, ZHANG Yong-qing, LI Jin. Study of displacement of bridge and abutment foundation caused by earth piling load and its prevention technique[J]. China Journal of Highway and Transport, 2004, 17(3): 74-77. (in Chinese) doi: 10.3321/j.issn:1001-7372.2004.03.015
[4]	李素华, 周健, 殷建华, 等. 摩擦型单桩承载性能设计理论研究[J]. 岩石力学与工程学报, 2004, 23(15): 2 659-2 664. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200415033.htm LI Su-hua, ZHOU Jian, YIN Jian-hua, et al. Study on bearing performance of friction pile foundation in complicated soil-layers[J]. Chinese Journal of Rock Mechanics and Engineering, 2004, 23(15): 2 659-2 664. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX200415033.htm
[5]	胡庆立, 张克绪. 大直径桩的竖向承载性能研究[J]. 岩土工程学报, 2002, 24(4): 491-495. doi: 10.3321/j.issn:1000-4548.2002.04.018 HU Qing-li, ZHANG Ke-xu. Research on axial bearing behavior of large diameter piles[J]. Chinese Journal of Geotechnical Engineering, 2002, 24(4): 491-495. (in Chinese) doi: 10.3321/j.issn:1000-4548.2002.04.018
[6]	李晋, 冯忠居, 谢永利. 大直径桩承载性状的数值仿真[J]. 长安大学学报(自然科学版), 2004, 24(4): 36-39. doi: 10.3321/j.issn:1671-8879.2004.04.009 LI Jin, FENG Zhong-ju, XIE Yong-li. Numerical simulation of large diameter hollow pile bearing performance[J]. Journal of Chang'an University(Natural Science Edition), 2004, 24(4): 36-39. (in Chinese) doi: 10.3321/j.issn:1671-8879.2004.04.009
[7]	JTJ 024-85, 公路桥涵地基与基础设计规范[S].
[8]	杜海珍, 荣见华, 傅建林, 等. 基于应变能的结构拓扑优化设计[J]. 交通运输工程学报, 2004, 4(3): 34-37. doi: 10.3321/j.issn:1671-1637.2004.03.009 DU Hai-zhen, RONG Jian-hua, FU Jian-lin, et al. Structural topology optimization design based on strain energy[J]. Journal of Traffic and Transportation Engineering, 2004, 4(3): 34-37. (in Chinese) doi: 10.3321/j.issn:1671-1637.2004.03.009
[9]	王磊, 马骉. 黄土地区公路排水系统病害防治[J]. 长安大学学报(自然科学版), 2003, 23(1): 15-18. doi: 10.3321/j.issn:1671-8879.2003.01.004 WANG Lei, MA Biao.Prevention and treatment for disasters of highway drainage system in loess[J].Journal of Chang'an University(Natural Science Edition), 2003, 23(1): 15-18.(in Chinese) doi: 10.3321/j.issn:1671-8879.2003.01.004