Study On Road Performance And Construction Technique Of Yunnan Red Clay

This paper, relying on Meng-Wen-Yan highway construction, through laboratory experiment and field test, studied deeply and systematically on road performance and construction technology.The main results are obtained as follows:1.By X diffraction experiment, the mineral of Yunnan red clay was studied, which the main mineral is quartz and only a little hydrophilic mineral is montmorillonite; To name after the soli, we studied on water ration limit including liquid limit and plastic limit of Yunnan red clay; According to particle analysis result,Yunnan red clay belong to fine grained soil; To study expansibility of Yunnan red clay,free expansive was studied that the soil is not expansive.2. Through the standard heavy compaction test, the effect of different sampling methods on the compaction effect of Yunnan red clay was studied, and the maximum dry density and optimum water content of red clay under wet and dry conditions were obtained; Through the heavy compaction test under different compaction work, the effect of different compaction work on the red clay of Yunnan was studied, and the maximum dry density and optimum water content of red clay filler under different compaction work were obtained; Through shaking table test, the effect of vibration frequency, amplitude and water content on dry density of Yunnan red clay was studied, and the maximum dry density of red clay filler under the optimum frequency and the optimum amplitude was obtained.3. The effect of compaction work and water content on the CBR of Yunnan red clay was studied by means of indoor test, and the variation law of CBR value with compaction and water content was obtained, which provided the basis for the road performance of red clay. The water stability of the red clay filler was studied by soaking swelling test, and the better water stability was obtained when the moisture content of the filler was more than 26%. Starting from the modulus of the red clay, the different degrees of compaction and moisture effect on red clay resilient modulus, the resilient modulus and moisture content using the power function fitting has good correlation; Through consolidation test, study the variation coefficient of compressibility of red clay with compaction degree and water content, the compression coefficient of red clay is less than 0.1 MPa-1, which belongs to the low compressibility of soil.4.Through the field compaction test,when the compaction water ratio in 27%~29%, loose paving thickness 25 cm, under the construction technology of vibratory road roller pressure again, weak vibration again and 4 times of the strong vibration with vibratory road roller, red clay embankment can obtain higher strength, better water stability. According to the indoor experimental research results, we preliminary discuss the basis and the scope to reduce the red clay compaction degree.