摘要
在基坑开挖过程中,基坑内外土压力失去平衡,往往会造成支护结构的过度变形。不同的支护体系在土压力的影响下所产生的变形也会有所差异。在软土地区,支护结构一般都会选择灌注桩重力式挡墙或灌注桩+内支撑的支护形式。近年来,一种利用反压土的无内支撑支护基坑形式得以应用于实际工程,其支护桩变形特点与常规有内支撑的基坑具有明显差异。为研究该支护形式与常规有内支撑支护形式的基坑支护桩水平位移的变化差异,本文选取了两开挖深度和土层类别接近的工程案例进行对比。通过分析其测斜监测结果,本文得出采用反压土隔墩支护的基坑其水平位移最大点位于基坑顶面,其最大位移不一定大于有内支撑的基坑,但须着重注意地表裂缝的结论。本文通过工程实例讨论了采用反压土隔墩支护的基坑支护桩水平位移变化规律,为该支护结构形式在工程实践中的科学应用积累了经验。
During the excavation of the foundation pit,if the soil pressure inside and outside the foundation pit loses its balance,it will result in excessive deformation of the supporting structure.Different support systems have different deformations under the influence of earth pressure.When located in soft soil areas,the supporting structure will generally be chosen as the filling pile gravity retaining wall or the filling pile with internal support.In recent years,a form of foundation pits using back pressure soil with no internal supports has been applied to practical projects,and the deformation characteristics of the supporting piles within it are significantly different from those of conventional foundation pits with internal supports.In order to study the difference between the horizontal displacement of this supporting form and the conventional supporting form of foundation pit supporting piles,this paper selects two engineering cases with similar excavation depths and soil types for comparison.By analyzing the monitoring results of the inclination,this paper concludes that the maximum horizontal displacement of the foundation pit supported by back-pressure soil piers is located on the top surface of the foundation pit,and the maximum displacement is not necessarily greater than that of the foundation pit with internal support,but special attention must be paid on the surface cracks.By studying the horizontal displacement change law of foundation pit supporting piles supported by back-pressure soil isolation piers through engineering examples,this paper accumulated a small amount of experience for the scientific application of this supporting structure in engineering practice.
作者
戴远俊
DAI Yuan-jun(Zhuhai Jinwan District Construction Project Quality Supervision and Inspection Station,Zhuhai 519090,China)
出处
《广东交通职业技术学院学报》
2021年第4期21-24,共4页
Journal of Guangdong Communication Polytechnic
关键词
反压土隔墩
水平位移
内支撑
支护结构
back-pressure soil isolation piers
horizontal displacement
internal support
supporting structure
