Comparison and Analysis of Three Methods for Obtaining the Elastic Modulus of Roadbed through Field Tests
In order to obtain the data of subgrade elastic modulus in the construction site,based on an expressway subgrade project in Guangdong Province,the experimental research on subgrade elastic modulus are carried out by means of bearing plate method,Beckmann beam method and falling weight deflectometer method.On the premise of clarifying the theoretical basis of obtaining subgrade elastic modulus by various methods,the experimental study of three methods and the comparison test between Beckmann beam method and falling weight deflectometer method are carried out in the experimental area.Based on the test results,the technical key points that should be followed in the field test of three test methods are put forward,and at the same time,it is proposed that the surface deflection and elastic modulus of subgrade should be controlled at the same time in the acceptance of subgrade.The results show that all three methods are based on elastic half-space theory,but there are some differences.Bearing plate method is a method to obtain rebound modulus directly on the subgrade site through rigid bearing plate.BB method is the method of obtaining the modulus of subgrade by back-calculation after obtaining the deflection at the center of double-circle load.The FWD method is a method of back-calculating the elastic modulus of the roadbed by obtaining the center deflection of the flexible bearing plate.Compared with bearing plate method and BB method,FWD method has higher automation and efficiency,and is less affected by human and environmental factors.Therefore,it is recommended to use this method for subgrade surface deflection test and back calculation of elastic modulus.
road engineeringelastic modulus of subgradefield testcomparison and analysis
万方数据
维普
