桩前预留土体对抗滑桩影响的分析与计算研究

Researches on the anti-slide pile with remainning soils in front of pile

本文在前人研究的基础上对桩前土体需要开挖的抗滑桩提出了一种新的计算方法,即似m法。文中将单排抗滑桩分为三类:第一类为桩前土体不开挖,但与抗滑桩分离形成桩后缝隙;第二类为桩前土体不开挖,但与抗滑桩相贴且有抵挡抗滑桩的作用;第三类为桩前土体需要开挖,并对各类抗滑桩给出了相应的设计计算方法。对于第一类抗滑桩可用本文改进的m法和有限线单元法计算;对于第二类抗滑桩考虑桩前抗力值大小后也可用本文改进的m法和有限单元法计算;对于第三类抗滑桩可用本文提出的似m法和改进的有限线单元法计算。通过与实际工程测量值对比分析,得出结论:在抗滑桩工程中对桩的钢筋受力进行实测以推断桩的受力性能,弥补滑坡推力及桩前抗力勘测、分析、计算值可靠性差的弱点。该方法与二维、三维有限元法相比,具有计算方法简单、可靠的特点,值得广泛应用和发展。

In this paper, the two calculation methods including M method and finite linear element method（FLEM） of anti-slide pile are improved based on the researches of the predecessors. The similar M method which is a new one to counter the excavation before the anti-slide pile is proposed. The problem of single row anti-slide pile is divided as three types： the first type is that the slope body before pile is not excavated but divorced from pile; the second type is that the slope body before pile is not excavated and is capable of resisting the anti-slide pile; the third type is that the slope body before pile is excavated. The calculation methods are established to every type of the anti-slide pile： the first type of anti-slide pile can be calculated and designed with M method and the FLEM improved in this paper; the second type of anti-slide pile can also be calculated and designed with the same methods but need count the resistant force of slope body before pile to pile; the another type of anti-slide pile can be calculated and designed with the similar M method proposed in this paper and the FLEM. A series of significant results are obtained comparing with practical engineering. For the safe and economy of engineering, the surveys of reinforcing bar stress in the anti-slide pile are praised highly to remedy the inaccurate of the determining of the landslide force and resistant force before pile. These methods proposed in this paper nearly suit every types of slope and it takes advantages of simply and reliably calculating compared with two-dimension and three-dimension finite element method. It is suggested to extensively use and develop these methods.