Triaxial loading

Ishida etal. [1997] Granite Triaxial loading Source location, fault-plane solution... 

On the contrary, in the case of laboratory investigations on rock specimens under uniaxial or triaxial load, volume changes in the source play an important role. Dilatancy can be explained as volume expansion caused by tensile opening. In contrast to the fault-plane solution method, the more complex moment tensor method is capable of describing sources with volumetric components like tensile cracks, deviatoric sources like shear cracks, or a mixture of both source types. The volumetric source components can be easily obtained using the isotropic part, or one-third of the moment tensor trace. With the moment tensor method, the source mechanisms are estimated in a least-squares inversion calculation from amplitudes of the first motion as well as from full waveforms of P and S waves. This method requires additional knowledge about the transfer function of the medium (the so-called Green s function) and sensor response. 

Manthei G (2005) Characterization of Acoustic Emission Sources in a Rock Salt Specimen under Triaxial Load. Bttll Seis Soc Amer 95 1674-1700 Martin CD, Yoimg RP (1993) The effect of excavation-induced seismicity on the strength of Lac du Bormet granite. In Yoimg RP (ed) (1993) Proc 3 Symp Rockbiusts and Seismicity in Mines (RaSiM 3), Balkema, Rotterdam, pp 367-371... 

It is found that after triaxial loading and unloading test for sandy clay Sample 2, many fissures generated and the sample were in a loose state through its microgram as shown in Figure 8. Compared with that before the test, there were more fissures around the particle and less pores in the sample. 

This presented that after the triaxial loading and unloading test the particles positions in this sandy clay sample had been adjusted. 

Zhuang, X.S. Zhao, X. He, S.X. 2007. An experimental study of soil mass deformability subject to true triaxial loads during unloading under drainage. Rock and Soil Mechanics 28(7) 1387-1390. 

For the reason given above, the latter problem was analysed separately for the biaxial and triaxial loading conditions. Stress concentration factors are derived for the biaxial loading condition. Additional stress concentration factors for the triaxial loading condition are calculated. The use of these factors is explained in many relevant text on stress concentration. 

The studies that have been conducted using this method thus far have provided insight into the similarities and differences in stress-strain behavior, morphological evolution, and fracture micromechanisms between uniaxial and triaxial loading conditions for different UHMWPE formulations. Because we have shown that UHMWPE formulation significantly affects the response to a notch, we believe that UHMWPE formulation must be considered... 

Pick, M. and Wronski, A. A. (1976) The effect of triaxial loading on the yielding and fracture properties of epoxy resins, Conf. on deformation, yield and fracture of polymers, Cambridge, Plastics Rubber Inst., London. 

More generally, Brandt et at. [71] found that SFRC was stronger than plain concrete under triaxial loading, particularly when tensile stresses were involved. 

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