Baoyin Sun^1,3, Shaofan Li³, Quan Gu^2,3,*, Jinping Ou¹

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 739-757, 2019, DOI:10.32604/cmes.2019.05085

Abstract Peridynamics (PD) is a widely used theory to simulate discontinuities, but its application in real-world structural problems is somewhat limited due to the relatively low-efficiency. The numerical substructure method (NSM) presented by the authors and co-workers provides an efficient approach for modeling structures with local nonlinearities, which is usually restricted in problems of continuum mechanics. In this paper, an approach is presented to couple the PD theory with the NSM for modeling structures with local discontinuities, taking advantage of the powerful capability of the PD for discontinuities simulation and high computational efficiency of the NSM. The structure is simulated using… More >

Alireza Sarebanha^1,*, Andreas H. Schellenberg², Matthew J. Schoettler³, Gilberto Mosqueda⁴, Stephen A. Mahin^†

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 693-717, 2019, DOI:10.32604/cmes.2019.04846

Abstract Hybrid simulation can be a cost effective approach for dynamic testing of structural components at full scale while capturing the system level response through interactions with a numerical model. The dynamic response of a seismically isolated structure depends on the combined characteristics of the ground motion, bearings, and superstructure. Therefore, dynamic full-scale system level tests of isolated structures under realistic dynamic loading conditions are desirable towards a holistic validation of this earthquake protection strategy. Moreover, bearing properties and their ultimate behavior have been shown to be highly dependent on rate-of-loading and scale size effects, especially under extreme loading conditions. Few… More >

Mohammed A. Mohammed¹, Andre R. Barbosa^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 583-627, 2019, DOI:10.32604/cmes.2019.06052

Abstract A three-dimensional nonlinear modeling strategy for simulating the seismic response of slender reinforced concrete structural walls with different cross-sectional shapes is presented in this paper. A combination of nonlinear multi-layer shell elements and displacement-based beam-column elements are used to model the unconfined and confined parts of the walls, respectively. A uniaxial material model for reinforcing steel bars that includes buckling and low-cyclic fatigue effects is used to model the longitudinal steel bars within the structural walls. The material model parameters related to the buckling length are defined based on an analytical expression for reinforcing steel bars embedded in reinforced concrete… More >

Quan Gu¹, Lei Wang¹, Surong Huang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.3, pp. 471-489, 2019, DOI:10.32604/cmes.2019.05757

Abstract Peridynamics (PD) is a powerful method to simulate the discontinuous problems in civil engineering. However, it may take a lot of effort to implement the material constitutive models into PD program for solving a broad range of problems. OpenSees is an open source software which includes a versatile material library and has been widely used by researchers and engineers in civil engineering. In this context, the paper presents a simple but effective approach to integrate PD with OpenSees by using a Client-Server (CS) software integration technique, such that the existing material constitutive models in OpenSees can be directly used by… More >

Liang Wu¹, Xiaorui Xiang¹, Yang Chen¹, Karrech Ali^2,*, Junru Zhou^1,*, Ming Chen³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 421-443, 2019, DOI:10.32604/cmes.2019.05218

Abstract During the excavation of deep rock, a sudden change in boundary conditions will cause the in-situ stress on the excavation surface to release instantaneously. This disturbance propagates in the form of an unloading stress wave, which will enlarge the damage field of surrounding rock. In this paper, the dynamic unloading problem of the in-situ stress in deep rock excavation is studied using theoretical, numerical, and experimental methods. First, the dynamic unloading process of rock is analyzed through adopting the wave equation, and the equivalent viscous damping coefficient of the material is taken into consideration. Calculations show that there is significant… More >

Chang-Chun Lee^1,*, Pei-Chen Huang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 239-260, 2019, DOI:10.32604/cmes.2019.06859

Abstract This research reviews the application of computational mechanics on the properties of nano/micro scaled thin films, in which the application of different computational methods is included. The concept and fundamental theories of concerned applications, material behavior estimations, interfacial delamination behavior, strain engineering, and multilevel modeling are thoroughly discussed. Moreover, an example of an interfacial adhesion estimation is presented to systematically estimate the related mechanical reliability issue in the microelectronic industry. The presented results show that the peeled mode fracture is the dominant delamination behavior of layered material system, with high stiffness along the bonding interface. However, the shear mode fracture… More >

John D. Clayton^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 333-350, 2019, DOI:10.32604/cmes.2019.06342

Abstract A theory invoking concepts from differential geometry of generalized Finsler space in conjunction with diffuse interface modeling is described and implemented in finite element (FE) simulations of dual-phase polycrystalline ceramic microstructures. Order parameters accounting for fracture and other structural transformations, notably partial dislocation slip, twinning, or phase changes, are dimensionless entries of an internal state vector of generalized pseudo-Finsler space. Ceramics investigated in computations are a boron carbide-titanium diboride (B₄C-TiB₂) composite and a diamond-silicon carbide (C-SiC) composite. Deformation mechanisms-in addition to elasticity and cleavage fracture in grains of any phase-include restricted dislocation glide (TiB₂ phase), deformation twinning (B₄C and β-SiC… More >

Ali Raza¹, Muhammad Shoaib Arif^1,*, Muhammad Rafiq², Mairaj Bibi³, Muhammad Naveed¹, Muhammad Usman Iqbal⁴, Zubair Butt⁴, Hafiza Anum Naseem⁴, Javeria Nawaz Abbasi³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 445-465, 2019, DOI:10.32604/cmes.2019.06454

Abstract This writing is an attempt to explain a reliable numerical treatment for stochastic computer virus model. We are comparing the solutions of stochastic and deterministic computer virus models. This paper reveals that a stochastic computer virus paradigm is pragmatic in contrast to the deterministic computer virus model. Outcomes of threshold number C^∗ hold in stochastic computer virus model. If C^∗ < 1 then in such a condition virus controlled in the computer population while C^∗ > 1 shows virus persists in the computer population. Unfortunately, stochastic numerical methods fail to cope with large step sizes of time. The suggested structure… More >

Yang Liu^1,*, Yue Qiao², Tiange Li³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 177-201, 2019, DOI:10.32604/cmes.2019.06338

Abstract This paper studies the effect of ice resistance on the icebreaking capacity and speed of an icebreaking vessel. We combine an improved Correct Smoothed Particle Method (CSPM) with a material low-speed collision fracture model to numerically simulate the continuous icebreaking and rolling process of crushed. Using this model, we investigate the icebreaking resistance and immersion resistance during the icebreaking process, taking into account the fluid (water) as the elastic boundary support and the fluid-solid coupling interaction. We compare the icebreaking resistance and broken ice fracture shapes obtained by the numerical calculation with the theoretical analytical results, and thus validate the… More >

Junjun Jiang¹, Congqing Wang^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 105-121, 2019, DOI:10.32604/cmes.2019.06277

Abstract Aircraft skin health concerns whether the aircraft can fly safely. In this paper, an improved mechanical structure of the aircraft skin inspection robot was introduced. Considering that the aircraft skin surface is a curved environment, we assume that the curved environment is equivalent to an inclined plane with a change in inclination. Based on this assumption, the Cartesian dynamics model of the robot is established using the Lagrange method. In order to control the robot’s movement position accurately, a position backstepping control scheme for the aircraft skin inspection robot was presented. According to the dynamic model and taking into account… More >