泡沫混凝土回填斜逆断层埋地管道管沟的数值模拟

Numerical simulation of backfilling buried pipe trenches crossing oblique reverse faults with foam concrete

管沟回填材料对保证埋地管道的安全至关重要,泡沫混凝土由于其自重小、强度可控、自密实等优良特性,为埋地管道管沟的回填材料提供了新选择。为研究泡沫混凝土对穿越斜逆断层的埋地管道的保护作用,采用泡沫混凝土对该种管道管沟进行回填,建立泡沫混凝土/砂土-管道-原状土穿越斜逆断层的非线性数值模型,对比泡沫混凝土与砂土回填管沟下管道的应力应变,并进一步分析泡沫混凝土主要性能参数对管道应变的影响。结果表明:在斜逆断层位错下,与砂土回填相比,泡沫混凝土回填埋地管道管沟能有效降低管道应力应变;对于泡沫混凝土,其较大的抗压强度对于降低管道的应变效果较好,但泡沫混凝土-管道的摩擦因数不宜过大,以能保证其对管道间的约束即可。研究结果可为泡沫混凝土回填跨断层埋地管道管沟的应用提供参考。

The backfilling material of pipe trenches is very important to ensure the safety of buried pipelines.Due to its small self-weight,controllable strength and self-compaction property,foam concrete is a preferred choice for backfilling buried pipe trenches.In order to study the protective effect of foam concrete on pipelines,buried pipe trenches crossing the oblique reverse faults were backfilled with foam concrete.Then,a nonlinear numerical model for buried pipelines crossing the faults in foam concrete/sand-pipeline-undisturbed soil structure was established through numerical simulation,so as to comparatively analyze the stress and strain of pipelines in the trenches backfilled with foam concrete and sand,respectively.Besides,the effect of the main performance parameters of foam concrete on pipeline strain was further analyzed.As shown by the results,compared with sand,the foam concrete backfilling buried pipe trenches could effectively reduce the stress and strain of pipelines under the dislocation of oblique reverse fault.Meanwhile,the great compressive strength of foam concrete has better effect on reducing the pipeline strain,while the friction coefficient of foam concrete and pipelines should not be too large but sufficient to ensure its friction with pipeline.Generally,the research results could provide reference for the application of foam concrete to backfill buried pipe trenches crossing the fault.