| The pavement of road engineering construction needs to consume a large amount of sand,gravel,gravel and other granular soil materials,but the natural sand and stone resources in our country are diminishing returns.Therefore,it can provide an effective way for sustainable development of road engineering to use reclaimed aggregate of construction waste instead of natural aggregate to construct granular pavement base/subbase.It is necessary to study the road performance of reinforced construction waste recycled granules considering the poor performance of recycled granules and the good improvement of geosynthetics.At the same time,pavement particles and soft soil are in a state of three-dimensional cyclic stress under traffic load,and their long-term deformation characteristics are closely related to the service performance of the road.Therefore,it is of great significance to further study the long-term cyclic dynamic characteristics of reinforced building waste recycled aggregate and soft clay under three-dimensional cyclic stress state.In this paper,with large-scale direct shear instruments and true triaxial equipment,a systematic experimental study was carried out on the shear strength,cumulative deformation and modulus of resilience and other road mechanical properties of reinforced building waste recycled particles and saturated soft clay foundation.The main research contents and results are as follows:（1）The static shear test and cyclic shear test of reinforced recycled aggregate are studied based on large-scale direct shear instrument.It is found that the increase of strength of geosynthetics increases the shear strength and shear stiffness of recycled aggregate,but reduces the cohesion and damping ratio to some extent.（2）The cyclic dynamic characteristics of reinforced recycled aggregate under three-dimensional stress state were studied by true（3）triaxial test.It is found that reinforcement increases the elastic modulus of soil,and the effect of reinforcement is more obvious with the increase of the cyclic principal stress level.However,the effect of reinforcement on the deformation of recycled granulated material is more complex.The more the number of reinforcement layers,the greater the deformation capacity.When the cyclic major principal stress amplitude is30 k Pa without geosynthetics,the strain ratio of 1,2 and 3 layers was reduced by 44%,31%and 39%,respectively.（4）Based on true triaxial tests,the partial drainage and undrained cyclic dynamic characteristics of saturated soft clay under three-dimensional stress state were studied.It was found that compared with undrained tests,the drainage conditions had a greater effect on the Cumulative deformation and resilience modulus of subgrade clay under traffic load.The clays undergo stiffness softening and hardening in partly drained and undrained conditions,respectively,and the effects of Cumulative deformation and resilience modulus on the stiffness evolution are very different between the two drainage conditions.Compared to undrained condition,partly drained leads to a great growth of permanent major principal strain up to 8.5 times for OCR=1,while for OCR=4 it is only 2.3,and the decrease of CSR and increase of bcycenhance the effects of partly drained condition on permanent major principal.（5）The evolution of complexε1p development behavior in three-dimensional stress state is explained through the cyclic major and intermediate principal stresses、the coupling of permanent shear strain and volumetric strain.The application of test results on the practical engineering is discussed. |
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