Research On The Rheological Property Of Irregular Limestone Particles Under Dry And Saturated States

Rockfill dam is a common water retaining structure.it’s main filling material are rockfill materials.Rokfill is the collection of rregular limestone particles.Factors as physical properties,geometric shape,size and arrangement of the large amount of particles lead to the macro rheological behavior of rockfill.A large number of indoor test results and field observation data show that for a long time after loading end under the condition of constant load,the rockfill dam shows obvious time-dependent behavior.Therefore,Controling the deformation of the dam body is an important problem when designing a rockfill dam.This requires to known the rheological properties of rockfill.and the effect on the mechanical properties of rockfill dam.This paper is a part of the project The impact of creep and damage caused by the contact between particles on macro rheological behavior of rockfill(NO.11372230),supported by the National Natural Science Foundation.This paper focus on irregular limestone particles from Lianghekou,to study the rheological behavior characteristics of limestone particles under the dry and saturated states.The main work of this paper are as follows:(1)The plates compression test on the regular specimens from Lianghekou was carried out in dry and saturated conditions.Mastered the instantaneous characteristics of limestone as the base of the load-shear rheological test.The results show that water has an impact on the the uniaxial compressive strength of the regular specimens.The results show that(2)The load-shear rheological test on the regular specimens from Lianghekou were carried out in dry and saturated conditions.Studied the rheological behavior characteristics of the regular specimens under the dry and saturated states as the base of the load-shear rheological test on the irregular limestone particles.The results show that specimens appears acceleration rheological stage under neither of two conditions.Saturated specimens have larger axial strain and longer initial rheological stage.(3)The plates compression test on the irregular limestone particles from Lianghekou site was carried out in dry and saturated conditions.In consideration of both the shapes and moisture content,the regression forecast model was built based on support vector regression machine(SVR).This model can forecast particles’ breaking force and reference data for preliminary predictions of the irregular particles’ breaking force.(4)The uniaxial compression rheological test on the irregular limestone particles from Lianghekou site was carried out in dry and saturated conditions.The results show that saturated limestone particles is easier to appears acceleration rheological stage.There are longer initial rheological stage,larger axial displacement and lower rheological collapsing strength under the saturated condition.