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Considering fracture constraint is an efficient way to describe stress–strain field and fracture toughness more accurately, so it is necessary to realise the relationship with in-plane and out-of-plane constraint for different standard specimens. In this paper, three-dimensional finite element method is applied to study the in-plane and out-of-plane constraint for both cruciform specimen and single edge notched bending specimen made from commercial pure titanium. Crack length and in-plane loading as the factors affecting in-plane constraint, and thickness as the factor affecting the out-of-plane constraint are used to study the effect on both in-plane and out-of-plane constraint in this paper. From the results, in-plane and out-of-plane constraint are both related to specimen geometries and loading styles. And there exist relationships with in-plane and out-of-plane constraint because of factors for different specimens. Depending on crack length, out-of-plane constraint increases with in-plane constraint. While depending on transverse loading, out-of-plane constraint decreases with in-plane constraint. In addition, when the in-plane constraint of a specimen is higher, in-plane constraint increases with out-of-plane constraint (thickness). When the in-plane constraint is lower, in-plane constraint almost remains unchanged with out-of-plane constraint.

For plates with an inclined crack of wide-range aspect ratios under biaxial loadings, T-stress values are calculated with three-dimensional finite element method. The results show that the normalized T-stress is crack length and orientation dependent. A linear equation for the relationship between normalized T-stresses and biaxility factors is proposed to describe the normalized T-stresses for different crack lengths and crack angles under different biaxial loadings, which is more convenient and involves wider biaxility ratios compared with the existing solutions. The plate thickness effect and the trend of normalized T-stresses along the crack front thickness are also studied for mode I and I–II mixed-mode cracks. Based on the analyses and comparisons, it is necessary to take the thickness effect into consideration when the crack length is long enough (a/W = 7/10). When the component of mode II is significant (β > 45°), and the biaxility ratios are negative, T-stresses near the free surface are lower than those at other positions, which are the opposite of mode I crack and most of I–II mixed-mode crack.

Analyses of I–II mixed mode central cracked plate by finite element method are performed in this paper, and some different phenomena are found. First for I–II mixed mode crack, the distribution of J integral along crack tip thickness depends on biaxiality factors because of the existence of vertex (corner) singularity, which is unlike that for mode I or mode II crack. Then J integrals at middle layer keep constant for any cracked plates with different inclined angles β when the biaxiality ratio is equal to 1 or −1, which implies that the inclined angle or the extent of I–II mixed mode has no effect on the J integral for positive or negative equal axial loading conditions. And the decreasing trend of J integral with the inclined angle β for biaxiality ratio λ being between−1 and 1 is just opposite with that for biaxiality ratio λ being larger than 1 and smaller than −1. Finally, proposed h1 (a/W, n, λ, β) of cracked plate with different inclined angles under different biaxial loading are calculated.

This study was undertaken to identify the sensory nerve endings in the monkey hip joint capsule. The capsules from six monkeys were stained in bulk by using a modified gold chloride method. Three morphologically distinct nerve endings: Type I, II and IV receptors resembling Ruffini end organs, Pacinian corpuscles and free nerve endings, respectively, were identified. The results showed that the hip joint capsules were densely innervated. Based on the present findings it is suggested that the monkey hip joint capsule is endowed with several types of afferent nerve endings, thus providing the anatomical basis for discriminating afferent outflow to the central nervous system. Clin. Anat. 11:81–85, 1998. © 1998 Wiley-Liss, Inc.