Numerous studies have focused on the mechanical properties of shale specimens to support hydraulic fracturing in gas engineering. However, failure modes containing a pre-existing flaw are still not clear. A series uniaxial compression tests were conducted coupled with acoustic emission (AE) technology and high-speed camera. slow enough variable loading speed scheme (0–50 kN: 0.1 kN/s, 50–100 0....

analytical detection of cracking in connections of steel moment resisting frames using simple damage indices is important since these cracks are not visible unless the connections are uncovered. in this paper, applicability of three cumulative damage indices for detection of cracking in a cover plate welded moment connection is investigated. the damage indices considered in this study are based...

Given that concrete masonry walls are expected to experience shrinkage combined with thermal expansion and contraction, and in some cases even carbonation, throughout their service life, cracking is to be expected. However, after concrete masonry walls have been placed into service, originally anticipated and accounted for cracking is often misdiagnosed as a structural defect. Such misdiagnoses...

Analytical detection of cracking in connections of steel moment resisting frames using simple damage indices is important since these cracks are not visible unless the connections are uncovered. In this paper, applicability of three cumulative damage indices for detection of cracking in a cover plate welded moment connection is investigated. The damage indices considered in this study are based...

This paper presents the results of an experimental study on the effect of limestone powder on the compressive strength, tensile behavior, and micromechanical parameters of a highly ductile cement composite incorporating limestone powder. Four mixtures were determined according to the replacement ratio of cement with limestone powder. A series of experiments including compressive strength, uniax...

Though many diagnostic PCR methods have been described, few techniques have been developed to rapidly and efficiently screen transformed bacterial colonies for plasmid presence (1). Unfortunately, PCR screening of a large number of colonies is time consuming and requires substantial amounts of polymerase and primers. In this report, we describe a two-step large-scale bacterial colony screening ...