基于FLAC3D的人工堆山稳定性分析

Numerical analysis of stability for artificial land-scape hill based on FLAC3D

建筑垃圾堆山造景,是目前城市建筑垃圾处理的有效途径。但堆山工程占地范围大,荷载高,会产生很多工程地质问题,严重影响工程体的稳定性。天津某拟建堆山工程地基中分布有厚度较大的软土层,加之拟建工程自荷载很大,在建造过程中会产生地面沉降、隆起等工程地质问题。本文以该工程为例,采用FLAC3D对软土地基上人工堆山稳定性进行研究,分别针对两种场景(天然基础、桩基础)模拟不同填筑高度条件下地基土竖、侧向位移分布。分析结果表明:采用桩基础的沉降量一般在30~90 cm,采用天然基础的沉降量一般可达30~270 cm;采用桩基础的侧向位移量一般在-12~11 cm,侧向变形较为均匀。采用天然基础,侧向位移量一般在-17~11 cm,侧向变形较不均匀。通过分析各监测线(点)竖、侧向位移变化曲线表明,相对于天然基础,采用桩基础后,各监测点处地基土变形均明显降低,整体变形量较均匀,变形差异减小。这说明布置桩基础可以有效控制堆山施工对周围环境的影响,为今后优化工程设计和施工方案提供有力依据。

Construction garbage heaping mountain and landscaping is an effective way to deal with urban construction garbage.However,due to the large area of the mountain and the high load,many engineering geological problems will arise.The stability of the mountain construction project has gradually attracted people’s attention.A soft soil layer with a large thickness is distributed in the foundation of a proposed mountainous project in Tianjin.In addition,the proposed project has a large self-load,and engineering geological problems such as land subsidence and uplift will occur during the construction process.Taking the project as an example,this paper studies the stability on soft soil foundation by FLAC3 D,and simulates the vertical and lateral displacement distribution of foundation soil under different filling height conditions for two scenarios(natural foundation and pile foundation).The analysis results show that the vertical displacement of the project using pile foundation is generally 30~90 cm,and the settlement with natural foundation can generally reach 30~270 cm;the lateral displacement of pile foundation is generally-12~11 cm,lateral deformation is more uniform.With natural foundation,the lateral displacement is generally-17~11 cm,and the lateral deformation is less uniform.By analyzing the monitoring curves of each monitoring line(point),it is shown that the deformation of the pile foundation soil at each monitoring point is significantly reduced compared with the natural foundation,the overall deformation is more uniform,and the deformation difference is reduced.This indicates that the layout of the pile foundation can effectively control the impact of the construction of the mountain on the surrounding environment,and provide a strong basis for optimizing the engineering design and construction plan in the future.