Abstract: Based on the mathematical similarity of the eigenvalue problem of the Reddy’s third-order
plate theory (RPT) and the classical plate theory (CPT), relationships between the solutions of
axisymmetric vibration or buckling of functionally graded material (FGM) circular plates based on
RPT and those of isotropic homogeneous circular plates based on CPT are presented, from which one
can easily obtain the RPT solutions of axisymmetric vibration or buckling of FGM circular plates
expressed in terms of the well-known CPT solutions of isotropic circular plates without much tedious
mathematics. Effects of rotary inertia are not considered in the present analysis. The relationships
obtained from the present analysis may be used to check the validity, convergence and accuracy of
numerical results of FGM plates based on RPT, and also show clearly the intrinsic features of the
effect of transverse shear deformation on the classical solutions.
Abstract: The current method of soil nail construction in Hong Kong is both labour intensive as well
as expensive and a search for new soil nail material is required. In the present pilot test, light weight
high strength and high corrosion resistance GFRP pipe with Tube a’ Manchette grouting technique is
used as soil nail instead of the conventional steel reinforcement. It is found that this material can be
handled easily on site with difficult access. From extensive laboratory as well as field tests, it is
demonstrated that this new soil nail technique has various advantages for use in Hong Kong and many
developed cities. The field test results on this innovative soil nail will be discussed in this paper.
Abstract: The viscosity-temperature curve of Bi melt showed that the viscosity values deceased
with the increase of temperature. However, the discontinuous changing pattern took place on the
viscosity curve. Viscosity of Bi melt can be divided into three parts as high temperature zone,
moderate temperature zone and low temperature zone according to its change rate with temperature.
The temperature ranges of the abnormal viscosity change were about 400~430°C and
610~640°C. With the DSC analysis, the abnormal phenomenon was explored from the
microscopic structure viewpoint. It was assumed that the change from inhomogeneous atom
configuration to homogeneous one led to the discontinuous variation, which is related to the bond
transformation with the increase of temperature in melt Bi.
Abstract: A series of numerical model tests were performed to investigate the behaviour of the
anisotropic rock surrounding circular excavations under high confining pressures. The aim was to
provide information on the formation of fractures and failure around deep level rock tunnels under
controlled conditions. Solid cubes containing a circular hole were confined to a vertical pressure with
same as the confinement in the horizontal directions. In this modeling, the inhomogeneous rock is
generated by using Weibull parameters which are related to the microstructural properties determined
by crack size distribution and grain size. The fracture angle is assumed to be 45o. The observed failure
zone around the excavation was simulated using both the maximum tensile strain criterion and
Mohr-Coulomb criterion respectively (as the damage threshold). And RFPA (Realistic Failure
Process Analysis) code was used as the calculating tool in this modelling, three opening modes are
simulated and compared. Computational model predictions that include crack propagation and failure
modes of rock show a good agreement with those of the observation in site. It is pointed out that the
damage evolution of EDZ strongly depends on the inhomogeneous, the excavation mode, anisotropic
property, and the various loading conditions. Concerning the existence of a weak plane, the amount of
displacement at the side wall of the tunnel was quite large, since the shear deformation occurred in
EDZ. The model is implemented in RFPA code and is able to represent the change in fracture patterns
between the solid and jointed parts. This provides confidence for the application of the numerical
model to the design of rock tunnels at great depth.
Abstract: Based on Green and Lindsay’s generalized thermoelasticity theory with two relaxation
times, a two-dimensional coupled problem in electromagneto-thermoelasticity for a rotating
half-space solid whose surface is subjected to a heat is studied in this paper. The normal mode
analysis is used to obtain the analytical expressions for the considered variables. It can be found
electromagneto-thermoelastic coupled effect in the medium, and it also can be found that rotation
acts to significantly decrease the magnitude of the real part of displacement and stress and
insignificantly affect the magnitude of temperature and induced magnetic field.
Abstract: Large particle-size, shallow groundwater level, and large permeate coefficient are the
characteristics of gravel stratum, which may results in large ground deformation. Ground deformation
depends on several factors. Using the RFPA2D-Flow software exploited by the Center for Rock
Instability and Seismic Research of Northeastern University (CRISR), the seepage-stress-deformation
coupling rules of soil, which are influenced by different soil distributing, drawdown, enclosure and
excavating, were analyzed, and the deformation of gravel in the dynamic balance due to the
interaction between seepage and stress is studied.
Abstract: The difference in microstructures of the base metal (BM), weld metal (WM) and
heat-affected zone (HAZ) in the weldment is one of the major reasons for the failure of the welded
equipments, which can be essentially attributed to the non-homogeneous corrosion occurred
electrochemically on the weldment. Therefore, it is necessary to explore the corrosion properties of
weldment. In this paper, the electrochemical behavior of SPV50Q steel weldment was investigated.
The polarization curves of BM, WM and HAZ in 5wt.%NaCl-0.5wt.%HAc solution containing H2S
were measured by potentiodynamic polarization. Interface characterization was also conducted by
electrochemical impedance spectroscopy (EIS). The results show the anodic curves are almost same
regardless of various pH or H2S content, but the cathodic curves show some difference. Relatively
large variation in corrosion current density (icorr) obtained by fitting technique exists among BM,
WM and HAZ. icorr of WM and HAZ is larger than that of BM, and icorr of WM is maximum.
According to EIS results, polarization resistance (Rp) increases in the orders of WM, HAZ and BM.
It is concluded that WM and HAZ are less resistant to corrosion than BM, which can be correlated
to the premature failure of the weldment serviced in H2S-containing environment such as sulfide
stress corrosion cracking (SSCC) and /or stress oriented hydrogen-induced cracking (SOHIC) etc.
Abstract: Stress corrosion cracking (SCC) of austenitic stainless steel serviced in aggressive
environment often occurs in power, petrochemical industry, and leads to premature equipment
failure and great economic loss. This paper focuses on the problem of the SCC on the 304L stainless
steel nozzle of a hydrogenation reactor, which is caused due to on-line alkali cleaning.
Susceptibility for SCC was evaluated by Slow Strain Rate Test (SSRT) for as-rolled and sensitized
304L stainless steel in low concentration sodium hydroxide solution with high temperature. The
effects of different strain rates, different concentration of sodium hydroxide and different solution
temperatures on SCC were investigated. On the basis of this, the contrast tests were also performed
in high temperature pure water. After SSRT, fractograph of the fractured specimens was analyzed
by using scanning electron microscopy (SEM).
Abstract: For applying acoustic radiation force to manipulate biomaterials such as cell, DNA,
bio-macromolecule without contact, stationary sound field of an ultrasonic transducer was computed
numerically. With the numerical data about the sound field, spatial distribution of the acoustic
radiation force was analyzed. Besides the radiation force in the axial direction, trapping forces in the
lateral direction were discovered. By moving the reflector continuously and carefully, positions of
trapping wells were changed simultaneously, as the result, non-contact manipulation of micro cells
Abstract: Superelastic shape memory alloys (SMAs) can experience large strains up to 8~10% and
restore residual strains just by removing the stress. By employing this unique characteristic of SMAs,
a new beam-to-column connection is presented in this paper. The proposed SMA connection consists
of an extended end-plate, eight long shank Nitinol SMA bolts, beam flange ribs, beam web stiffeners
and continuity steel plates for reinforcing column flanges. In order to predict the behavior of SMA
connection, 3-D solid finite element models are set up in ANSYS. The numerical results indicate that
the local buckling of beam is avoided and a plastic hinge forms at beam-to-column interface when the
moment-carrying capacity of bolt cluster is below the elastic flexural capacity of connecting beam.
The SMA connection shows stable moment-rotation hysteresis curves with re-centering capability,
which demonstrates the connection’s self-healing deformations function. Far different from energy
dissipated by steel yield in traditional connection, the SMA connection shows moderate energy
dissipation capacity, and this amount of energy is mainly dissipated by the superelastic behavior of
SMA bolts. Moreover, the connection model shows a large inelastic rotation capacity beyond 0.03 rad.
The ductility of SMA connection is deeply influenced by the length of SMA bolts, and the 2.2 times
length of normal bolt is suggested for SMA bolts.