云南松侧根摩擦型根土粘合键的破坏机制及模型

以云南松侧根为研究对象，探讨了侧向牵引情况下，云南松测根与土壤之间摩擦型根土粘合键的力学作用机制，阐述了侧根从土中拔出时，摩擦型根土粘合健破坏的实质，并基于莫尔-库仑破坏准则建立了极限平衡条件下的摩擦型根土粘合键破坏模型。该模型除了可以描述摩擦型根土粘合键的破坏原理外，还可用于定量地估算、预测摩擦型根土粘合健能够提供的最大牵引阻力。最后，通过实测与模型理论计算结果进行了比较，结果表明，所建立的模型具有一定的精度和适用性。

Study for the Destroy Principle and Model of the Yunnan Pine's Lateral Root-soil Friction Bond

Today, using vegetation to protect and steady slope has been an important content in the ecologically protecting slope engineering. Therefore, researchers made many quantitative studies for the mechanical effect of reinforcing soil and steadying slope caused by plant roots. Now, there is a basic opinion among researchers as to this problem. It suggests that the action of plant roots reinforcing soil is caused by vertical roots and lateral roots mainly. Lateral roots can improve the soil layer's whole tensile strength. Vertical roots can make the shallow soil layer anchored to the deep soil layer. These will increase the soil layer's moving resistance, reinforce the soil layer, and restrain soil layer coast. Following some quantificational studies for the lateral root traction being developed, some models have been established to forecast the lateral root traction effect. But these models are imperfect with low precision because of lacking in deep research to the root soil bond's function regulation and destroy principle. The root soil bond, which is a kind of mechanical action at interface between root and soil, is an important factor for the lateral root traction. The strain can be passed between soil and lateral roots only because of existence of the root soil bond. So, it is obvious that ignoring studying dynamic function principle of the root soil bond deeply is an important reason to make the model have a low accuracy. Now, seeking more accurate and more perfect model is still a warm work in this field. In this paper, with Yunnan pine's lateral roots being a research object, we discuss the dynamic function regulation of the Yunnan pine's root soil friction bond, and describe the destroyed essential of the root soil friction bond when lateral roots are pulled out from soil. Further more, based on the Mohr Coulomb destroy theory, the destroy model of root soil bond is established under the utmost balance condition. This model can not only depict the destroy principle of the fiction root soil bond, but also be used to quantificationally estimate and forecast the traction resistance provided by the friction root soil bond. Then, the difference between theoretical result and experimental testing result shows that the model has good accuracy and applicability.