Abstract In this research, the failure mechanism and anomalous behavior of intact jointed rock block having a circular tunnel under compression are studied. This was done by monitoring progressive subjected to uniaxial loading. The tests were conducted in sandstone blocks “ Acoustic Emission ” (AE) technique used identify crack damage other attributes. Three cases have been considered i.e. rock...

The effect law of deformation and failure a jointed rock mass is essential for underground engineering safety stability evaluation. In order to study the evolution mechanism precursory characteristics instability masses, uniaxial compression acoustic emission (AE) tests are conducted on sandstones with different joint dip angles. To simulate mechanical behavior rock, damage constitutive model A...

Numerical testing is an ideal method in the research on mechanical behaviors of jointed rock. However, there are few systematic studies focused comparison between two-dimensional (2D) and three-dimensional (3D) simulation effects rock behaviors, particularly those In this paper, a particle flow model was established by utilizing PFC2D PFC3D to represent materials, (especially rock) (uniaxial co...

BACKGROUND An essential prerequisite for the future widespread application of human induced pluripotent (hiPSCs) and embryonic stem cells (hESCs) is the development of efficient cryopreservation methods to facilitate their storage and transportation. METHODS We developed a simple and effective freezing/thawing method of single dissociated hESCs and hiPSCs in a feeder-free culture in the prese...

Abstract Studies on stress wave propagation across persistent joints have been conducted extensively. Nevertheless, there exists a consensus that non-persistent are widely and densely distributed, which profound impact in jointed rock masses. A boundary integral equation method is suggested this paper to investigate the characteristics of transmitted field for case single joint. The displacemen...

one of the complications of twinning of mono chorionic mono amniotic gestations is conjointed twins. structural congenital malformations occur in 5 % to 7 % of twin gestations versus only 3 % of singleton births. most defects occurring in only one of the twin fetuses. occasional anomalies such as omphalocele sincenomalia heart defect one reported in both concordance. the structural defect commo...

The objective of this study is to experimentally investigate how the rough joints effect stress wave propagation through jointed rocks coupling joint matching coefficient (JMC) and roughness (JRC). Split Hopkinson Pressure Bar (SHPB) apparatus was adopted conduct uniaxial compression experiments on specimens. (JRC) are introduced as morphology parameters estimate roughness. Based SHPB experimen...