›› 2017, Vol. 38 ›› Issue (7): 1856-1862.doi: 10.16285/j.rsm.2017.07.002

• 基础理论与实验研究 • 上一篇    下一篇

筒型基础在粉质黏土中的静压沉放试验研究

练继建1, 2,马煜祥1, 2,王海军1, 2,王芃文1, 2,蒋杏雨1, 2   

  1. 1. 天津大学 水利工程仿真与安全国家重点试验室,天津 300350;2. 天津大学 建筑工程学院,天津 300350
  • 收稿日期:2015-08-31 出版日期:2017-07-10 发布日期:2018-06-05
  • 通讯作者: 王海军,男,1978年生,博士,副教授,主要从事水工结构与风电基础静动力特性研究。E-mail: bookwhj@163.com E-mail:tju_luntan@126.com
  • 作者简介:练继建,男,1965年生,博士,长江学者特聘教授,院长,从事水利枢纽工程和风能工程安全研究。
  • 基金资助:

    国家创新研究群体科学基金(No. 51321065);高等学校学科创新引智计划资助(No. B14012);国家国际科技合作专项资助(No. 2012DFA70490);天津市海洋经济创新发展区域示范专项(No. cxsf2014-15)。

Experimental study on static pressure sedimentation for bucket foundation in silty clay

LIAN Ji-jian1, 2, MA Yu-xiang1, 2, WANG Hai-jun1, 2, WANG Peng-wen1, 2, JIANG Xing-yu1, 2   

  1. 1. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300350, China; 2. School of Civil Engineering, Tianjin University, Tianjin 300350, China
  • Received:2015-08-31 Online:2017-07-10 Published:2018-06-05
  • Supported by:

    This work was supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (51321065) , the Program of Introducing Talents of Discipline to Universities (B14012), the International Science & Technology Cooperation Program of China(2012DFA70490)and Tianjin Regional Demonstration Program for Marine Economical Innovation and Development (cxsf2014-15).

摘要: 筒型基础是一种常见的海洋基础型式,其成功地沉放就位是正常使用的前提。故针对筒型基础,在均匀粉质黏土中开展了不同长径比的模型静压沉放试验,得到了筒型基础在静压沉放过程中的筒端和筒壁内外压力的变化情况。试验结果表明:筒内压力呈双折线形式,筒外压力线性增加,筒壁的侧向挤压是产生筒内压力的主要原因,筒内的挤土效应明显高于筒外;筒外的挤土程度为上部小,下部大,并与土塞增长率IFR成线性关系;筒端阻力与土的强度直接相关。根据规范,基于不排水剪强度和静力触探(CPT)可较准确的计算筒侧阻力和端阻力,由于挤土效应的差异,计算筒内阻力时的?、kf要取较大值。在基础沉放过程中主要阻力由端阻转变为侧阻,静压阻力和土塞的发展对0.1~0.2 cm/s之间的下沉速度不敏感,长径比L/D在1~2间的筒型基础的挤土效应和阻力特性是相近的。

关键词: 筒型基础, 静压沉放, 挤土效应, 沉放阻力

Abstract: Successful installation of bucket foundations, a common foundation in ocean engineering, is a prerequisite for normal use. Static pressure sedimentation tests on the bucket foundations with different length-to-diameter ratios are performed in homogeneous silty clay to determine the change of pressure inside and outside the cylinder wall and the cylinder end during the static pressure sedimentation process. The results show that the inner pressure is in the form of double broken line. The outer pressure increases linearly, and the lateral extrusion of the wall is the main reason for the inner pressure generation. The soil squeezing effect in the interior wall is much significant than the exterior wall. The soil squeezing extent of the exterior is small on the upper portion and large on the lower portion of the foundation, which has a linear relationship with the IFR. The tip resistance is directly related to the strength of the soil. According to the standard, based on the undrained shear strength and the CPT, the lateral and tip resistance can be calculated accurately. Due to the difference of soil squeezing effect, ? and kf will take larger value when the inner resistance is calculated. The major part of resistance is tip resistance, and then lateral resistance becomes the major during installation. The resistance and the development of soil plug are not sensitive to the speed range of 0.1-0.2 cm/s. The soil squeezing effect and resistance characteristic of bucket foundations with length-to-diameter ratio between 1 and 2 are similar.

Key words: bucket foundation, static pressure sedimentation, soil squeezing effect, submergence resistance

中图分类号: 

  • TU 43

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