草本植物根系网固土原理的力学试验探究

An Experimental Study on Herb Plant Root System for Strength Principle of Soil-fixation

通过试验测定了生物软措施草本植物根系的最大拉力及最大拉力作用下根系断裂面直径 ,计算植物根系最大抗拉强度 ,结果表明香根草根系平均抗拉强度 85 m Pa>假俭草 2 7.3m Pa>白三叶 2 4 .6 m Pa>莎草 2 4 .5 m Pa>宜安草 19.7m Pa>马尼拉草 17.5 m Pa>狗牙根 13.4 m Pa。土壤剪切力试验表明香根草根系 +沙土处理 >沙土对照 ,香根草根系 +黏土 >黏土对照。探讨了草本植物根系网的固土性能 ,提出根系最大抗拉强度代表根系材料的受力潜能 ,可作为评判根系网的固土刚性的一个有效指标 ,为利用生物软措施代替或部分代替工程措施的作用 。

An experiment is conducted for testing the greatest strength of herb root system meanwhile measuring the root diameter under the condition of the greatest tensile strength. It provids where root was tore out and the potential root tensile strength is caculated. The result was revealed that the root average tensile strength vetiver grass of 85 mPa> common cetipede grass of 27.3 mPa> white clover of 24.6 mPa> Juncelles serotinus of 24.5 mPa > paspalum dilatatum poir of 19.7 mPa > Bahio grass of 19.2 mPa > manila grass of 17.5 mPa > Bermuda grass of 13.4 mPa. The shear strength test shows that the soil plus vetiver grass root made the shear strength increased, compared to the CK in sandy or clay soil. The feature of holding up soil of herb root network is discussed and the potential capacity of holding up soil ie. the tensile strength of root network is put forword as one of the most important factor. It justifies the basic mechanics theories substituding soft bioengineering approach for the hard engineering approach in completely or partially to hold up soil and slope and resistant against soil erosion and control the landslide and mud rock flow etc.