Veturia Chiroiu¹, Ligia Munteanu² and Antonio S. Gliozzi³

CMC-Computers, Materials & Continua, Vol.19, No.1, pp. 1-16, 2010, DOI:10.3970/cmc.2010.019.001

Abstract This paper develops a mechanical model for multifunctional reinforced carbon nanotube (CNT) beams. The model is obtained by introducing the couple stresses into the constitutive equations of linear viscoelastic theory. The material functions are determined using the homogenization method. More >

E.J. Sapountzakis¹, J.A. Dourakopoulos¹

CMC-Computers, Materials & Continua, Vol.18, No.2, pp. 121-154, 2010, DOI:10.3970/cmc.2010.018.121

Abstract In this paper a boundary element method is developed for the nonlinear flexural - torsional analysis of Timoshenko beam-columns of arbitrary simply or multiply connected constant cross section, undergoing moderate large deflections under general boundary conditions. The beam-column is subjected to the combined action of an arbitrarily distributed or concentrated axial and transverse loading as well as to bending and twisting moments. To account for shear deformations, the concept of shear deformation coefficients is used. Seven boundary value problems are formulated with respect to the transverse displacements, to the axial displacement, to the angle of twist (which is assumed to… More >

C. Jiang¹, Y.C. Bai¹, X. Han^1,2, H.M. Ning¹

CMC-Computers, Materials & Continua, Vol.18, No.1, pp. 21-42, 2010, DOI:10.3970/cmc.2010.018.021

Abstract In this paper, an efficient interval optimization method based on a reliability-based possibility degree of interval (RPDI) is suggested for the design of uncertain structures. A general nonlinear interval optimization problem is studied in which the objective function and constraints are both nonlinear and uncertain. Through an interval order relation and a reliability-based possibility degree of interval, the uncertain optimization problem is transformed into a deterministic one. A sequence of approximate optimization problems are constructed based on the linear approximation technique. Each approximate optimization problem can be changed to a traditional linear programming problem, which can be easily solved by… More >

Oliver K. Johnson¹, Calvin J. Gardner¹, David T. Fullwood¹, Brent L.Adams¹, Nathan Hansen², George Hansen²

CMC-Computers, Materials & Continua, Vol.15, No.2, pp. 87-112, 2010, DOI:10.3970/cmc.2010.015.087

Abstract A novel nickel nanostrand-silicone composite material at an optimized 15 vol% filler concentration demonstrates a dramatic piezoresistive effect with a negative gauge factor (ratio of percent change in resistivity to strain). The composite volume resistivity decreases in excess of three orders of magnitude at a 60% strain. The piezoresistivity does decrease slightly as a function of cycles, but not significantly as a function of time. The material's resistivity is also temperature dependent, once again with a negative dependence.
The evidence indicates that nickel strands are physically separated by matrix material even at high volume fractions, and points to a charge… More >