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...

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...

Bamboo-bundle laminated veneer lumber (BLVL) was produced by joint lengthening technology. The objective of this study was to evaluate the effect of joint form and the values of key parameters on mechanical properties of BLVL. Two joint forms, i.e., finger joint and scarf joint, and two corresponding joint parameters, i.e., finger length and scarf angle, were investigated in laminates. The resu...

Insect cuticles have been a model system for the study of planar polarity for many years and a number of genes required for this process have been identified. These genes organise the polarised arrangement of hairs on the legs, wings, thorax, and abdomen of adult Drosophila. It has previously been shown that four-jointed is involved in planar polarity decisions in the eye as well as proximal di...