The Contrast Research On Compaction Tests Of Typical Dry And Wet Subgrade Soil In South Warm-Wet Area

As the basis of the pavement structure, subgrade is not only to bear their fill and overlying the gravity of the pavement structure, in addition, it need to support the traffic load from the upper road. For a long time, there has always been in road engineering research the phenomenon of "heavy road, light subgrade", result in subgrade construction technology related research lags behind. During the process of subgrade construction, the amount of moisture containing in subgrade had a great influence.on the quality of subgrade filling, an inappropriate treatment will be readily causing the damages such as unbalanced settlement,rutting,dehiscence,etc.Serious impact on road use performance and service life of the road. China southern humid area subgrade humidity is bigger, so the southern humid area highway subgrade soil typical differences between dry and wet compaction test and find different corresponding subgrade soil moisture content to guide the reasonable construction of subgrade pavement design is of great significance.Based on the construction of nanchang to camphor tree highway reconstruction project as the backing,focused on the typical subgrade soil in warm-wet area of the south,expanding the study of subgrade soil of test in-and-out door. In this thesis, it consisted two parts:firstly, under the circumstance of warm-wet climate in south,the relationship between the best moisture containing in dry-method and wet-method of different sorts of typical subgrade soil, for future highway subgrade construction to provide more reliable basis and laws. Zhang high-speed sections of the reconstruction and selective in chang three types of soil samples collected:general clay, high liquid and limit soil conducted respectively screening test of soil, liquid plastic limit test of soil compaction test, dry-wet method of compaction test, and analyzes the basic soil-features and engineering specificity of soil samples, the three kinds of typical south highway subgrade soil dry and wet compaction test corresponds to the relationship between the optimum moisture content. Second, on the foundations of compaction test to obtain the best rate of moisture containing, the two sides according to the moisture content of 2%-3% increase (decrease), subgrade strength (CBR) test research, work out CBR value of the corresponding subgrade soil, make an evaluation to pavement performance of the road subgrade soil,puts forward three kinds of typical southern humid area of subgrade soil under the premise that meet the engineering requirements, the range of moisture containing rate in corresponding embankment construction,analyzed that the relationship between the best amount of moisture containing of different kinds of soil and CBR value.This article through to the south highway subgrade soil related studies, three typical has the following innovative:by analyzing the test results, summarized and worked out the relationship among three kinds dry-wet compaction tests and the best amount of moisture containing, and the range of moisture containing that can satisfy the construction requirements. After for the southern region of typical subgrade soil filling embankment has a guiding significance.