Study On The Micro-pore Characteristics And Structure Of Q₃ Loess In Lv-liang Mountainous Area

Studying of loess structure and the establishment of micro structure model of loess play an important role in the loess area,especially in the Loess Plateau region-disaster prevention and mitigation and guiding engineering construction.In this paper,L₁ loess in Lvliang Mountain area is included in the analysis system,which integrates the selection of loess sampling location,routine analysis and testing of samples,micro testing and typical mechanical experiments,so as to preliminarily explore the relationship between micro pore characteristics and macro mechanical indexes(structure index).The main achievements are as follows:(1)The particle fraction test shows that the L₁ loess in Lvliang Mountains area is dominated by powder and clay particles.For the L₁ layer loess,all particle sizes are concentrated between 0 and 0.25 mm,and the content of clay particles(d?0.005 mm)is in6.06%?11.45%;the natural water content of this layer of loess ranges from 3.6%to 12.2%;the plastic index of L₁ loess to the west of Lvliang Mountain ranges from 8.88 to 14.68,with an average value of 11.40;the plastic index range of L₁ loess to the east of Lvliang Mountains area From 8.32 to 15.97,the average value is 13.466.(2)Through CT scanning analysis and evaluation of loess samples,the results show that the proportion of micro-pores in loess is the highest,and the proportion of macro-pores that have an important influence on structural strength is the smallest.(3)The L₁ loess in the Lvliang Mountains area shows a softening stress-strain curve;the structure index decreases with the increase of water content;the harder the soil,the stronger its structure,and the larger the structure index;consider the dry density and At the initial porosity,the larger the ?_d/e₀,the larger the configuration index.(4)Structure index has polynomial function relation with the average aperture,face clearance and roundness,and fitting effect is good.