There is much interest in the concept of creating bioartificial tissues by reconstituting monomeric type I collagen into a fibrillar network, entrapping cells of interest in the process. An intrinsic property of such "tissue-equivalents" is the compaction of the collagen network due to traction exerted by the entrapped cells - a cell-induced gel syneresis. The rationale design of tissue analogs therefore requires a continuum mechanical model that accounts for the ensuing mechanical interplay: cell traction drives network deformation that induces fibril alignment, which in turn induces cell contact guidance. An anisotropic biphasic theory for tissue-equivalent mechanics is described, including the determination of the various constitutive equations (e.g. collagen network viscoelasticity and cell contact guidance), its validation in simplifying geometries, and its application to fabrication of circumferentially-aligned smooth muscle cell/collagen tubes as an analog of the medial layer of a bioartificial artery.