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The objective of this article is to investigate the effect of the vibration mixing process (VMP) on the performance of cement stabilized recycled aggregate (CSRA). The ordinary mixing process (OMP) was also used for comparative analysis with the VMP. The performance of CSRA with different cement content was tested and comprehensively analyzed by the unconfined compressive strength test, dry shrinkage test, and temperature shrinkage test. The results showed that compared with OMP, VMP can greatly improve the compressive strength, dry shrinkage, and temperature shrinkage properties of CSRA. The optimum parameters of vibration time and vibration frequency in VMP were 30 s and 40 Hz, respectively. The reason why VMP can improve the performance of CSRA was that VMP strengthened the aggregate and interface transition zone and introduced microbubbles to optimize the pore structure. [ABSTRACT FROM AUTHOR]

The objective of this article is to investigate the effect of the vibration mixing process (VMP) on the performance of cement stabilized recycled aggregate (CSRA). The ordinary mixing process (OMP) was also used for comparative analysis with the VMP. The performance of CSRA with different cement content was tested and comprehensively analyzed by the unconfined compressive strength test, dry shrinkage test, and temperature shrinkage test. The results showed that compared with OMP, VMP can greatly improve the compressive strength, dry shrinkage, and temperature shrinkage properties of CSRA. The optimum parameters of vibration time and vibration frequency in VMP were 30 s and 40 Hz, respectively. The reason why VMP can improve the performance of CSRA was that VMP strengthened the aggregate and interface transition zone and introduced microbubbles to optimize the pore structure. [ABSTRACT FROM AUTHOR]

A numerical finite element (FE) analysis technology is presented for efficient and reliable solutions of rock with hydraulic-mechanical (HM) coupling, researching the seepage characteristics and simulating the damage evolution of rock. To be in accord with the actual situation, the rock is naturally viewed as heterogeneous material, in which Young’s modulus, permeability, and strength property obey the typical Weibull distribution function. The classic Biot constitutive relation for rock as porous medium is introduced to establish a set of equations coupling with elastic solid deformation and seepage flow. The rock is subsequently developed into a novel conceptual and practical model considering the damage evolution of Young’s modulus and permeability, in which comprehensive utilization of several other auxiliary technologies, for example, the Drucker-Prager strength criterion, the statistical strength theory, and the continuum damage evolution, yields the damage variable calculating technology. To this end, an effective and reliable numerical FE analysis strategy is established. Numerical examples are given to show that the proposed method can establish heterogeneous rock model and be suitable for different load conditions and furthermore to demonstrate the effectiveness and reliability in the seepage and damage characteristics analysis for rock. [ABSTRACT FROM AUTHOR]