冻土切削力学特性的试验和理论分析  

An Experimental and Theoretical Investigation on the Cutting Resistance of Frozen Soil

作　　者：张招祥[1] 余群[1] 

机构地区：[1]北京农业工程大学

出　　处：《冰川冻土》1994年第2期104-112,共9页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金

摘　　要：利用笔者所研制的冻土切削试验台，在室内对不同冻土在不同温度、含水量、切削速度、切削深度和切刀前角下进行了一系列切削试验。结果表明，切削时，冻土主要呈脆性断裂破坏，其切削过程被认为是刀刃切入和撕裂冻土的结果，切削阻力随冻土温度降低而非线性增加，随切削速度提高而略有增加，随切削深度增加而近似线性增加，最佳切刀前角随切削深度增大有增大趋势。但平均切削阻力与最大切削阻力之比值对不同试验条件基本在０．４－０．６５间变化。同时，根据切削过程机理，从理论上建立了最大切削力模型，此模型考虑了切入和撕裂冻土阻力。A sefics of cutting tests on frozen soils were conducted by means of an apparatus devel-oped by the authors to investigate variations of frozen soil cutting with temperature, watercontest, cutting velocity, cutting depth and rake angle, etc. It is found that the main failure offrozen soil during cutting is due to brittle fracture. The cutting process is deseribled as thecombination of blade penetrating into and tearing away frozen soil. Cutting resistance in-creases nonlinearly with decreasing of temperature, but increases nearly linearly as cuttingdepth increases. There is a slight increase of the resistance with increase of cutting velocity.The optimal rake angle tends to increase when cutting depth increases.The ratio of meanforce over peak force remains in the range of 0．4-0．65 for various testing parameters. Atheorelical model to prodict the peak cutting resistance is also obtained based on the mecha-nism of cutting frozen soil.

关 键 词：冻土 切削力学 切削模型 试验 

分 类 号：P642.14[天文地球—工程地质学]