Testing system and method for split resilient modulus of pavement material

Abstract

The invention discloses a testing system and method for the split resilient modulus of a pavement material. The system comprises a test piece of the pavement material and further comprises a multi-functional MTS (material testing system), a front resistance strain gauge, a back resistance strain gauge, a strain acquisition instrument and a data processing terminal. The method comprises steps as follows: radial symmetric loading is performed on the test piece by the aid of the multi-functional MTS, the resistance strain gauges are bonded to positions, perpendicular to the loading direction, in the center of the test piece and are used for measuring the tension strain in the horizontal direction of the positions, the tension strain is substituted into a split resilient modulus computation formula, and the more accurate split resilient modulus can be obtained. With the adoption of the improved testing method, the more accurate horizontal resilient strain of a specific test part of the test piece and the resilient modulus corresponding to the horizontal resilient strain can be obtained, the computation error caused by integral statistical averaging of deformation is avoided, the testing accuracy and the testing efficiency of the pavement material are improved, and more accurate structural design parameters can be provided for scientific design of a durable pavement.

Description

technical field [0001] The invention relates to an indoor testing technology for modulus of road materials in the field of road engineering, in particular to a testing system and method for splitting rebound modulus of semi-rigid base material and asphalt mixture. Background technique [0002] Under the action of vehicle load, each structural layer of the pavement is in a complex stress state. In order to better simulate the stress state of the actual pavement structure, the test methods for material modulus in the current pavement material test regulations are mainly divided into compressive rebound modulus test, bending tensile rebound modulus test and splitting rebound modulus test. test. Both the compressive modulus of resilience test and the flexural-tensile modulus of resilience test are carried out when the material is under unidirectional stress, and it is difficult to accurately reflect the true mechanical properties of the pavement material. The splitting modulus...

AI Technical Summary

Problems solved by technology

Whether it is the entire springback deformation in the horizontal radial direction or the total vertical springback deformation, it reflects the sum of the radial deformation of the entire specimen and cannot reflect the strain value corresponding to the stress state. The modulus value obtained accordingly It is also difficult to objectively reflect the real deformation resistance of materials under different stress and strain states. The reason is that under the conditions of the split test, the stress states of each point inside the specimen are different, and different stress states will cause various stress states inside the specimen. The current test procedure calculates the splitting modulus of the pavement material by measuring the total deformation in the horizontal direction or the total deformation in the vertical direction of the test piece. This modulus is only a statistical average concept, which is used as the pavement material Performance metrics are biased

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