摘要
将增敏微型光纤光栅传感器(以下简称FBG传感器)、土压力传感器成功应用于静压桩室内模型试验中,对贯入黏性土地基中双壁开口试桩TP1压桩力、桩端阻力、桩身内外管轴力、内外管侧摩阻力、单位侧摩阻力等的发展变化情况进行了监测。试验结果表明:FBG传感器、土压力传感器能较好地监测沉桩过程中的桩身受力状态。开口试桩TP1的压桩力、桩端阻力、桩内外管侧摩阻力均随着沉桩深度的增加而逐渐增大,而不同贯入深度下的内外管桩身轴力逐渐递减且斜率逐渐减小。静力沉桩过程中土塞逐渐形成并趋于稳定,沉桩结束时土塞高度超过3L/100。在沉桩过程中,随着贯入深度的增加,同一沉桩深度处桩侧水平应力逐渐释放,桩侧摩阻力出现“退化效应”。沉桩结束时,外管侧摩阻力值是内管侧摩阻力值的3倍。
The sensitized miniature fiber Bragg grating sensor(hereinafter referred to as FBG sensor)and the earth pressure sensor are successfully applied to the indoor model tests of static pressure piles.The developmental changing rules for the pile pressing force of the double-walled open testing pile in the clay foundation,the end resistance,the axial force of the inner and outer tubes of the pile,the side friction resistance of the inner and outer tubes and the friction resistance at the unit side are monitored.The testing results show that the FBG sensor and the earth pressure sensor can better monitor the stress state of the pile during the pile sinking process.The pile pressing force of the open testing pile TP1,the pile end resistance,and the lateral friction resistance of the inner and outer tubes of the pile gradually increase with the increase of the pile depth,while the axial force of the inner and outer tube piles at different penetration depths gradually decreases and the slope gradually decreases.During the static pile sinking process,the soil plug is gradually formed and stabilized,and the height of the soil plug exceeds 3L/100 at the end of the pile.During the pile sinking process,with the increase of the penetration depth,the horizontal stress of the pile side is gradually released at the same pile depth,and the side frictional resistance has a“degradation effect”.At the end of the pile sinking,the lateral friction resistance of the outer tube is three times that of the inner tube.
作者
张明义
孙绍霞
王永洪
桑松魁
苗德滋
Zhang Mingyi;Sun Shaoxia;Wang Yonghong;Sang Songkui;Miao Dezi(School of Civil Engineering,Qingdao Technological University,Qingdao 266033,China;Collaborative Innovation Center for Engineering Construction and Safety of Blue Economic Zone,Shandong Province,Qingdao 266033,China)
出处
《工程勘察》
2019年第12期1-8,29,共9页
Geotechnical Investigation & Surveying
基金
国家自然科学基金资助项目(No.4177231,No.51778312,No.51809146)
山东省重点研发计划项目(No.2017GSF16107,No.2018GSF117010,No.2018GSF117008)
关键词
FBG传感器
土压力传感器
开口试桩
土塞
静力压桩
FBG sensor
earth pressure sensor
open testing pile
soil plug
static pressure pile
