Preparation method and evaluation of reshaped broadly weak consolidated rock for full-size hob rock breaking test

SONG Zhaoyang; WANG Qiang; ZHANG Tongzhao; ZHANG Guangyu; WANG Yuan; CUI Zesheng

doi:10.19458/j.cnki.cn11-2456/td.2024.02.012

Abstract：In order to realize the indoor hob crushing weakly consolidated rock test,it is one of the key technologies to obtain the large volume rock sample for the hob cracking test.Due to the characteris-tics of weakly cemented rock such as low particle cementation degree,easy weathering,easy hydroly-sis and sensitive disturbance,large undisturbed rock blocks used for indoor hob rock breaking test can't be directly sampled and processed,and can't meet the needs of hob rock breaking test.Based on the diagenetic characteristics of weakly consolidated rock dominated by granular matter under the ac-tion of sedimentation and accumulation,argillaceous cementation and alteration,and the characteristics of strong plasticity under certain pressure and cementation,a preparation method for reshaping weakly consolidated rock by hob breaking test was proposed.The preparation ratio of re-shaped general weak cemented rock sample for hob rock breaking test is determined,and the formed rock sample is evaluated and tested.The formation mechanism of large volume rock samples with weakly reconstructed cementation was expounded.The results show that the uniaxial compressive strength of the reconstructed weakly consolidated rock sample ranges from 1.2 to 43 MPa with differ-ent ratio schemes and loading forces.When the uniaxial compressive strength of the rock sample is 12 MPa and 43 MPa,the longitudinal wave velocity of the rock sample is 1.42 km/s and 3.14 km/s,respectively.The prepared weakly consolidated bulk rock sample belongs to the category of weakly consolidated rock in terms of uniaxial compressive strength,wave velocity and failure form,which solves the problem of the lack of weakly consolidated bulk rock sample in hob rock breaking test.