T' -W. Chou and R. kamiya and modeling of the thermo-mechanical behavior of the textile composites, using the concepts of micro-and macro-cells; and (5)characterization of textile composite The loading conditions considered here are simple. The reinforcement and pre form requirements for multi-axial loading can be approximated through superpo- sition of those developed for the basic loading conditions. The preforming tech niques considered in this study include braiding, weaving, stitching and knitting he analytical techniques applied include those for thermo-elastic analysis, damage mechanics, and fracture toughness Ceramic matrix composites based upon 2D and 3D textile preforms have been fabricated using chemical vapor infiltration, slurry infiltration and preceramic polymer infiltration. Examples of damage initiation and evolution in textile ceramic matrix composites, as affected by the fiber architecture will be discussed 2. IDENTIFICATION OF LOADING CONDITIONS The basic loading conditions encountered in structural elements can be categorized as follows. (I) uni-axial tension of a rod element (2)torsion of a cylindrical rod (3)internal pressure loading of a thin-walled cylinder; (4)in-plane bi-axial tension of a plate: (5) in-plane shear of a plate (6)transverse loading of a thick plate (7)flexural loading of a bean Multi-axial and combined loading conditions can be constructed from superposition of these simple loading conditions 3. REQUIREMENTS OF FIBER REINFORCEMENT The requirements of fiber reinforcement of a structural element composed of fiber composite material can be readily determined from the loading condition specified in Section 2. The resulting fiber reinforcement directions are illustrated in Fig. I It should be noted that the fiber placement strategy here is only based upon a consideration of the strength of the load-bearing element. Factors such as buckling and local stress concentration are not taken into account. Some comments in regard to the fiber orientation and volume content are given below in reference to the espective loading conditions of Section 2 (I)The uni-axial fiber orientation is suggested for reason of simplicity. Fibers in he transverse directions can be added if the reduction of axial Poisson's ratio is needed