| The roadbed is an important foundation of the pavement structure.It supports all the loads on the pavement structure and above.The bearing capacity of the roadbed directly determines the overall performance of the road,and the quality of the roadbed will affect the performance of the pavement structure.The occurrence and extent of such.Roads in the use of the process,the road will often appear a variety of diseases,and most of these diseases because of the lack of roadbed strength caused.Therefore,a solid and stable and meet the needs of the roadbed is to ensure the overall good performance of the road to ensure the safety of transport key.The resilient modulus is an important index for highway subgrade design,construction control and acceptance testing,and it can make an accurate evaluation of the quality performance of subgrade.But the elastic modulus is affected by soil,water content,compaction and other factors,the numerical determination is more difficult,especially the special soil subgrade rebound modulus,the specification did not give the recommended value,plus The detection method used in the actual detection will be different,which is caused by the unity of the results.Therefore,it is necessary to study the rebound modulus of special soil subgrade,and compare the test results of common detection methods,and draw the conclusion of their applicability and accuracy.In this paper,the influence of moisture content and compaction on the resilient modulus is analyzed.A kind of expressway is used as the research carrier to analyze the gravel and loess roadbed by FWD.Comparison between the plate method and the Beckman method.The regression model is used to analyze the correlation between the different indexes,and the results show that the measured changes of the three kinds of test methods are consistent and can be objective.To make an accurate evaluation of the roadbed performance.Based on the actual situation of this project,FWD,bearing plate and Beckman beam were used to detect the same gravel soil subgrade and the test section of loess roadbed,which proved that the crushed soil used in this section Subgrade quality,performance is much better than loess roadbed.Through the simple economic comparison,although the use of crushed earth as a roadbed filler,the construction cost is much lower than the use of loess,but the roadbed quality has been significantly enhanced,a greater degree of protection of the use of the road function to extend the service life,Conservation frequency and cost. |
