Papers by Author: Hao Ran Chen

Abstract: This article demonstrates the buckling behavior of an advanced grid stiffened (AGS) composite plate under an axial loading. The experimental results acquired by a fringe projection profilometry system shows that the buckling of the AGS plate would gradually evolved from a local skin buckling to a global ribs buckling during the experiment. Kinds of failure mode would arise while the loading increasing, though an impressive peak loading was recorded before the AGS plate was crush. The whole-field deformation of the AGS plate during the experiment was retrieved by the fringe projection profilometry system.

Abstract: This article demonstrates the co-curing process for AGS plate. Based on the phenomenological models of resin flow and cure kinetic, the variations of temperature, cure degree and pressure were illustrated during the process by a 2D FEA program. Some valuable results were obtained that the distribution of coupling fields could be more uniform with a proper cure cycle and mold, and the resin flow action would be completed in 6000s since the pressure was applied.

Abstract: The blast-resistant of an aluminum foam sandwich structure under impact has been investigated. Plastic deformation and load distributions in each of the sub-layers during and after impact were calculated by the material point method with the consideration of strain rate effect on deformation of the aluminum foam. The numerical results from the 3D material point method modeling show that the blast-resistant capability of the aluminum foam sandwich structure is excellent, and the energy absorbability of the structure would be underestimated if the strain rate effect on the aluminum foam is ignored.

Abstract: Based on the first order shear deformation plate theory, a numerical analysis model of composite laminated plates with distributed PZT actuators under thermal load was established, and the corresponding formulae of finite element method were presented considering the effect of adhesive layer between PZT actuator and plate. For a two ends simply supported plate, the thermal deformation of the plates induced by different temperatures on the upper and lower surfaces and the thermal deformation compensation for the plates using PZT actuators were studied, then the optimization of voltages applied to each actuator was discussed.

Abstract: This work investigated the post buckling strength and failure behavior of advanced grid stiffened structures (AGS) under thermal-mechanical load using a finite element method. Based on the first order shear deformation theory (FSDT), Von Karman non-linear deformation assumption, and a progressive failure criterion, the buckling, large deformation，local failure modes in the AGS were studied. The thermal effect was also analyzed. By some numerical examples, the failure characteristics of the AGS were discussed.

Abstract: Biaxial compressive tests of plain concrete specimens suffering 0、25、50 and 75 cycles of freezing and thawing respectively in 3.5% sodium chloride solution imitated seawater were completed under four lateral constant stress rates. The tests were completed by using the large static-dynamic triaxial test system for concrete in the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology. The biaxial compressive strength and deformation characteristics of concrete confined by lateral stress after suffering corrosive cycles of freezing and thawing were studied in a systematic way. On the basis of the tests, the failure criterion of concrete subjected to constant lateral compressive stress after suffering corrosive cycles of freezing and thawing was established in the stress-strain system. The conclusions can provide the testing and theoretical basis for deeper study of the concrete construction subjected to biaxial compressive combined loads in northern cold region or influenced by corrosive cycles of freezing and thawing nearby the coastal and offshore area.

Abstract: The dynamic stress intensity factor was studied about the Griffith crack between the visco-elastic layer and elastic body under shear loading. Adopting integral transform and singular integral equation method, the time response of dynamic stress intensity factor was calculated. Considering the influence of materials parameter, it was found that the dynamic stress intensity factor increases with crack length increasing, and it posses distinct size effect when the thickness of visco-elastic layer reaching the character size of materials.

Abstract: In accordance with Helliger-Reissner variational principle, a semi-analytical Hamiltonian method has been developed for analyzing the process-induced stress analysis of composite wound vessel with metal liner during the curing process. A typical numerical result indicates that the process-induced thermo-stress fields involve complex variations of gradient and multi-peak values at different stages during the curing process.