岩土力学2026，Vol.47Issue(1)：140-148,159,10.DOI:10.16285/j.rsm.2025.0441
根系衰亡对根-土复合体力学性能的影响
Effect of root decay on mechanical properties of root-soil composite
摘要
Abstract
Plant roots undergo a life cycle of growth,maturation,and decay,yet the effect of dynamic process of this cycle on the mechanical behavior of the root–soil composite have been largely overlooked.Long-term deterioration of root–soil mechanical properties caused by root decay is a critical consideration in assessing the durability of ecological slope-protection structures.Using Masson pine–covered slopes in Wuping County,Fujian Province as the study subject,this paper employs single-root tensile tests and large-scale direct shear tests on root–soil composites to systematically investigate the evolution of root mechanical properties during mortality dynamics and the corresponding changes in the shear strength of the root–soil composite.The results show that the tensile strength and ultimate tensile force of Masson pine roots decrease exponentially with decay duration.In the early stage of decay,tensile strength declines rapidly by 30%–50%,after which the degradation rate gradually levels off.Root decay significantly affected the shear strength of the root–soil composite:the root-conferred additional cohesion decreases progressively with decay duration,whereas the internal friction angle remains essentially unchanged.Based on the experimental data,we developed a power-law model for root tensile strength and an exponential-decay model for composite shear strength.We further modified the Wu model by introducing a cohesion-decay coefficient to quantify the decay-duration-dependent reduction in shear strength.These findings clarify the mechanism by which root decay undermines soil reinforcement and provide a theoretical basis for long-term stability assessment and maintenance planning of ecological slope-protection projects.关键词
根系衰亡/根-土复合体/单根拉伸试验/大型直剪试验/浅层滑坡Key words
root decay/root-soil composite/single-root tensile test/large-scale direct shear test/shallow landslide分类
建筑与水利引用本文复制引用
吴宜龙,简文彬,林昀昭,朱祖腾,郑国明..根系衰亡对根-土复合体力学性能的影响[J].岩土力学,2026,47(1):140-148,159,10.基金项目
国家自然科学基金(No.U2005205). This work was supported by the National Natural Science Foundation of China(U2005205). （No.U2005205）
