白龙运动场边坡稳定性及加固分析

【作者】 唐正光；

【导师】 徐则民；

【作者基本信息】 昆明理工大学 ， 工程力学， 2006， 硕士

【摘要】 白龙运动场边坡自1997年雨季发生滑坡以来，于1998年，采用人工挖孔桩与混凝土挡墙进行治理，然而边坡整治没有达到预期的效果，随着时间的推移，边坡变形越来越明显，尤其中段危险段侧移变形，导致坡顶出现较大裂逢、沉降。1999年雨季，边坡再次发生滑坡；2000年，采用预应力锚钉挡土墙进行治理，也没有达到预期的效果，观测资料反映，中段边坡侧向破坏变形仍在继续，边坡目前处于不稳定状态。此边坡经过两次治理，历时5年之久，还没有稳定，表明本边坡是一个典型的复杂的土质边坡稳定性问题。用非饱和土理论来分析雨水诱发滑坡的内在机理，同时采用极限平衡理论来模拟分析边坡前期和当前的稳定状态，通过改变土体的抗剪强度指标C、f值来模拟非饱和土--水特性变化，模拟雨水对边坡稳定性的影响，得出此边坡滑移变形的真正原因：降雨是诱发此次滑坡的真正原因，本滑坡属于边坡上部的非饱和土的浅层滑坡。对边坡实地进行了详细的地形图测量，获得可靠的边坡地形资料、剖面图，另外，通过多次深入实地对边坡进行勘察，很好了解和掌握了边坡目前表现出来的现象，获得了边坡的全面资料。依据极限平衡理论分析边坡加固后的稳定性得出：边坡安全系数K随着预应力地锚力的降低而下降。针对白龙运动场边坡问题，边坡目前的不稳定状态是由于抗滑桩锚固力不够、预应力地锚力失效所致。地下水在白龙运动场边坡工程中起到了破坏的作用，降低土体的抗剪强度，是边坡失稳、变形的根源。边坡经过治理后，边坡上部得到加固，边坡内部的应力进行了重分布。采用有限单元法、有限差分法对边坡的应力、变形进行了分析计算，得出了边坡的变形趋势，为边坡加固分析提供可靠数据。针对上述计算分析的结果，提出边坡加固方案一：抗滑桩加固边坡分别按弹性桩和刚性桩对抗滑桩进行了设计计算。边坡加固方案二：边坡土体加固注浆加固边坡土体和降低边坡土体含水加固边坡通过对白龙运动场边坡的稳定性及加固分析，总结了边坡分析治理的方法。更多还原

【Abstract】 During the rainy season in 1997,BaiLong playground slope slided, manpower-dig-hole-picket and concrete wall was constructed to fasten the slope in 1998,however repair not meet anticipation.As time goes on,the deformation of slope geted expand,especially the middle segmentmid, resulting in crack and subside at the crest of slope. In 1999 rainy season, slided further,pre-stress anchor-nail was adopted to fasten the slope in 2000 with the same result. Observation data shows BaiLong playground slope is still in a state of instability,and its side deformation continues in middle segmentEndured two repairs in five years, The slope is not still stable.So it indicates that the slope stability problem is typical of complicated soil slope.By applying the theory of inherent mechanism of rainwater inducing a premium on slope with non-saturatied soil,simulating slope stability in prophase and current with limit equilibrium of soil,changing soil’s resist shear intensity index value of C(cohesion) and f to simulated non-saturatied soil-water characteristic change,to simulate stability variation from water to slope,conclusion can be made that rainfall was the real cause of slid which located on the fleet layer of non-saturatied soil in the top of slope.By measuring the slope in detail on the spot,accurate landform information and section plane drawing can be obtained,In addition, many reconnaissance on the slope helps find out current evidence of slope and achieve full informations of slope which is needed for studing the slope.Analzing the slope after repair with limiting equilibrium theory indicates that safety factor K goes down with the declining of pre-stress anchor-hold. The instability state of BaiLong playground slope was caused by anchor-hold of anti-slide pile and invalidation of pre-stress anchor-pire.Groundwater reduces resist shear intensity of soil,destructed stability of the BaiLong playground slope, resulting in slope deformation.The two repairs have reinforced the top of the slope,and the stress of the slope has been redistributed distribut. Analzing the slope with FEM(finite elements method) and FDM(finite difference method) contributes to finding the deformation trend of the slope,offening reliable data for reinforce.On the base of the abave analysis,the first reinforce scheme is anti-slide pile to reinforceslope.Design and calculate anti-slide pile on theory of elasticity pile and rigidity pile.The second reinforcing scheme: reinforce soil of slope.Pour plasm and reduce containing water to reinforce the soil of the slope.The paper summarizes methods of analysing and reinforcing slope on the base of analyzing stability and reinfotcement (a cast study) of BaiLong playground slope.更多还原