桩挤土现象的若干问题的思考
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摘要
随着我国现代化建设的深入发展，民用高层建筑、工业厂房、公路、机场、铁路等领域有很大发展，被开发利用的土地越来越多，因此，桩基础被使用的概率越来越高。挤土桩的施工对周边的土体产生挤压，造成邻近建(构)的变形，进行导致建(构)筑物的正常使用功能被破坏，这个问题在深厚软土发育地区显得尤为突出。
本论文的主要任务是努力认识清楚，在施工现场，实际打桩过程中，桩周土的附加应力响应和附加位移的响应，揭示出桩挤土现象的内在本质，以及所牵涉到的影响因素。
为了达到这一目标，本论文完成的主要工作有以下几个方面：
对沉桩过程中桩挤土在桩周土中所产生的位移场、应力场等问题进行计算分析，该计算既考虑桩周土的弹性性能，也涉及土的塑性性能；能够回答出桩周土行为对附近其它既有构造物所产生的不良影响与土的性质(弹性模量、内摩擦角、粘性土的粘聚力等)间的定性与定量关系。
结合实际工程，考察理论解对理想模型中的桩周土行为的描述与现实桩体周围土的行为实测资料之间的关系，确定出这两者之间的一致的地方和不同之处。尽可能地减少同一问题的理论解答与实测资料之间的偏差，从而更有效地发挥理论推导解答对实际施工的指导作用。
基于已有现场实测到的资料，尝试提出对论文前面提出的理想模型改进的意见和建议。
With further development of construction in China, there is much achievement in several fields, such as buildings of skyscrapers, building highways, railways, airports, and so on. As a result, more and more lands have been used. So have the pile foundations. Pile driving has squeezing effect on the soil in the vicinity, and the squeezing may cause damage on surrounding buildings, which is prominent in soft clay.
The task the essay includes is getting the answers to questions of stress and displacement of the soil with the pile into soil, and the factors that do something with the questions, showing the reason for the behavior of soil, which is around the pile.
For the sake of achieving the task, things that have been done are as follows:
Firstly, answers are gotten according to foundations of elasticity and plasticity theories.
Secondly, all the answers are tested by the fact in order to show whether hypotheses found from theory are true or not. If the equations are right, they could be used to guide doing actually. If the data is inadequate or contrary to the expectations which have been gotten before, it should be written honestly and completely. Then the third section would be done.
Thirdly, some modifications to the results obtained from theory should be done, basing on the report of the experiment.
本论文的主要任务是努力认识清楚，在施工现场，实际打桩过程中，桩周土的附加应力响应和附加位移的响应，揭示出桩挤土现象的内在本质，以及所牵涉到的影响因素。
为了达到这一目标，本论文完成的主要工作有以下几个方面：
对沉桩过程中桩挤土在桩周土中所产生的位移场、应力场等问题进行计算分析，该计算既考虑桩周土的弹性性能，也涉及土的塑性性能；能够回答出桩周土行为对附近其它既有构造物所产生的不良影响与土的性质(弹性模量、内摩擦角、粘性土的粘聚力等)间的定性与定量关系。
结合实际工程，考察理论解对理想模型中的桩周土行为的描述与现实桩体周围土的行为实测资料之间的关系，确定出这两者之间的一致的地方和不同之处。尽可能地减少同一问题的理论解答与实测资料之间的偏差，从而更有效地发挥理论推导解答对实际施工的指导作用。
基于已有现场实测到的资料，尝试提出对论文前面提出的理想模型改进的意见和建议。
With further development of construction in China, there is much achievement in several fields, such as buildings of skyscrapers, building highways, railways, airports, and so on. As a result, more and more lands have been used. So have the pile foundations. Pile driving has squeezing effect on the soil in the vicinity, and the squeezing may cause damage on surrounding buildings, which is prominent in soft clay.
The task the essay includes is getting the answers to questions of stress and displacement of the soil with the pile into soil, and the factors that do something with the questions, showing the reason for the behavior of soil, which is around the pile.
For the sake of achieving the task, things that have been done are as follows:
Firstly, answers are gotten according to foundations of elasticity and plasticity theories.
Secondly, all the answers are tested by the fact in order to show whether hypotheses found from theory are true or not. If the equations are right, they could be used to guide doing actually. If the data is inadequate or contrary to the expectations which have been gotten before, it should be written honestly and completely. Then the third section would be done.
Thirdly, some modifications to the results obtained from theory should be done, basing on the report of the experiment.
引文
1. Cooke, R. W. (1974). The settlement of friction pile foundation. Proc. Conf. on Tall Buildings, Kuala Lumpur
2. Griffiths, D. V. , Clancy, P. and Randolph, M. F. (1991). Piled raft foundation analysis by finite elements. Proc. 7th Int. Conf. on Comp. Methods and Adv. in Geomech. , Vol. 2
3. Horikoshi, K. and Randolph, M. F. (1996). Centrifuge modeling of piled raft foundations on clay. Geotechnique Vol. 46, No. 4
4. Jendeby, L. (1986). Friction piled foundations in soft clay—a study of load transfer and settlements. Chalmers University of Technology
5. Poulos, H. G. (1972). Load-settlment prediction for piles and piers. J. Soil Mech. Found. Engrg. Div. , Vol. 98, No. SM9
6. Randolph, M. F. & Worth, C. P. (1979). An analysis of vertical deformation of pile groups. Geotechnique Vol. 29, No. 4
7. Sowers, G. F. et al. (1961). The bearing capacity of friction pile groups in homogeneous clay from model studies. Proc. 5th ICSMFE, Paris 2.
8．陈仲颐，叶书麟(1990)．基础工程学．中国建筑工业出版社
9．傅永华(2003)．有限元分析基础．武汉大学出版社
10．龚晓南(1999)．土塑性力学．浙江大学出版社
11．龚晓南(2002)．复合地基理论及工程应用．中国建筑工业出版社
12．蒋镇华，龚晓南，曾国熙(1996)．成层土单桩有限里兹单元法分析．浙江大学学报，Vol．30 No．4
13．雷晓燕(2000)．有限元法．中国铁道出版社
14．王元汉，李丽娟，李银平(2001)．有限元法基础与程序设计．华南理工大学出版社
15．杨克己，韩理安(1992)．桩基工程．人民交通出版社
16．杨敏，艾智勇(1997)．沉降控制设计桩基础的理论、方法和计算．同济大学地下建筑与工程系
17．杨敏，赵锡宏(1992)．分层土中的单桩分析方法。同济大学学报，Vol．20 No．4
18．伊颖锋，施建勇，周清华(2002)．土体弹塑性本构模型研究概述．岩土工程师，Vol．14 No．2
19．郑颖人，沈珠江，龚晓南(2003)．岩土塑性力学原理．中国建筑工业出版社
20．龚晓南(1996)．高等土力学．浙江大学出版社
21．杨克己，韩理安(1992)．桩基工程．人民交通出版社
22．杨贵通(2004)．弹塑性力学引论。清华大学出版社
23．罗惟德(1990)．单桩承载机理分析与载荷—沉降曲线的理论推导．岩土工程学报，Vol．12 No．1
24．徐志英．岩石力学．水利电力出版社．
25．刘亚莲，李永见，茜平一(2002)．竖向荷载下复合桩基承台特性的弹塑性分析．中国农村水利水电，9：32～34
26．谢康和，周健(2002)．岩土工程有限元分析理论与应用．科学出版社
27．伊颖锋，施建勇，周清华(2002)．土体弹塑性本构模型研究概述．岩土工程师，Vol．14 No．2
28．宰金珉(2001)．半解析半数值方法在岩土工程中的几项应用．全国第七届岩土力学数值分析与解析方法讨论会论文集．大连理工大学出版社
29．宰金珉(1995)．桩土明确分担荷载的复合桩基及其设计方法．建筑结构学 报，Vol．16 No．4
30．宰金珉(2001)．塑性支承桩—卸荷减沉桩的概念及其工程应用．岩土工程学报，Vol．23 No．3
31．郑颖人，沈珠江，龚晓南(2003)．岩土塑性力学原理．中国建筑工业出版社
32．黄昱挺，朱向荣，林柏(1994)．复合桩基沉降初探．浙江省第六届土力学及基础工程学术讨论会论文集．浙江大学出版社
33．J．塔罗勃著，林天健等译．岩石力学．中国工业出版社，1965年．
2. Griffiths, D. V. , Clancy, P. and Randolph, M. F. (1991). Piled raft foundation analysis by finite elements. Proc. 7th Int. Conf. on Comp. Methods and Adv. in Geomech. , Vol. 2
3. Horikoshi, K. and Randolph, M. F. (1996). Centrifuge modeling of piled raft foundations on clay. Geotechnique Vol. 46, No. 4
4. Jendeby, L. (1986). Friction piled foundations in soft clay—a study of load transfer and settlements. Chalmers University of Technology
5. Poulos, H. G. (1972). Load-settlment prediction for piles and piers. J. Soil Mech. Found. Engrg. Div. , Vol. 98, No. SM9
6. Randolph, M. F. & Worth, C. P. (1979). An analysis of vertical deformation of pile groups. Geotechnique Vol. 29, No. 4
7. Sowers, G. F. et al. (1961). The bearing capacity of friction pile groups in homogeneous clay from model studies. Proc. 5th ICSMFE, Paris 2.
8．陈仲颐，叶书麟(1990)．基础工程学．中国建筑工业出版社
9．傅永华(2003)．有限元分析基础．武汉大学出版社
10．龚晓南(1999)．土塑性力学．浙江大学出版社
11．龚晓南(2002)．复合地基理论及工程应用．中国建筑工业出版社
12．蒋镇华，龚晓南，曾国熙(1996)．成层土单桩有限里兹单元法分析．浙江大学学报，Vol．30 No．4
13．雷晓燕(2000)．有限元法．中国铁道出版社
14．王元汉，李丽娟，李银平(2001)．有限元法基础与程序设计．华南理工大学出版社
15．杨克己，韩理安(1992)．桩基工程．人民交通出版社
16．杨敏，艾智勇(1997)．沉降控制设计桩基础的理论、方法和计算．同济大学地下建筑与工程系
17．杨敏，赵锡宏(1992)．分层土中的单桩分析方法。同济大学学报，Vol．20 No．4
18．伊颖锋，施建勇，周清华(2002)．土体弹塑性本构模型研究概述．岩土工程师，Vol．14 No．2
19．郑颖人，沈珠江，龚晓南(2003)．岩土塑性力学原理．中国建筑工业出版社
20．龚晓南(1996)．高等土力学．浙江大学出版社
21．杨克己，韩理安(1992)．桩基工程．人民交通出版社
22．杨贵通(2004)．弹塑性力学引论。清华大学出版社
23．罗惟德(1990)．单桩承载机理分析与载荷—沉降曲线的理论推导．岩土工程学报，Vol．12 No．1
24．徐志英．岩石力学．水利电力出版社．
25．刘亚莲，李永见，茜平一(2002)．竖向荷载下复合桩基承台特性的弹塑性分析．中国农村水利水电，9：32～34
26．谢康和，周健(2002)．岩土工程有限元分析理论与应用．科学出版社
27．伊颖锋，施建勇，周清华(2002)．土体弹塑性本构模型研究概述．岩土工程师，Vol．14 No．2
28．宰金珉(2001)．半解析半数值方法在岩土工程中的几项应用．全国第七届岩土力学数值分析与解析方法讨论会论文集．大连理工大学出版社
29．宰金珉(1995)．桩土明确分担荷载的复合桩基及其设计方法．建筑结构学 报，Vol．16 No．4
30．宰金珉(2001)．塑性支承桩—卸荷减沉桩的概念及其工程应用．岩土工程学报，Vol．23 No．3
31．郑颖人，沈珠江，龚晓南(2003)．岩土塑性力学原理．中国建筑工业出版社
32．黄昱挺，朱向荣，林柏(1994)．复合桩基沉降初探．浙江省第六届土力学及基础工程学术讨论会论文集．浙江大学出版社
33．J．塔罗勃著，林天健等译．岩石力学．中国工业出版社，1965年．