One of the main objectives of micromechanics is to predict the effective elastic properties of composites. Most existent explicit micromechanics models are based on an assumption of isotropic matrices and on that only 2-phase constituent materials are involved. In reality, a composite may possess a 3rd interphase between the fiber and the matrix, which is generally transversely isotropic. Accordingly, the prediction of the elastic properties of a 3-phase composite can be achieved through the combination of 2 kinds of 2-phase composites, to which a micromechanics model with transversely isotropic matrix should be applicable. The explicit bridging tensor elements to correlate the internal stresses of a transversely isotropic matrix with those of a reinforcing fiber in a concentric cylinder assemblage (CCA) model were derived firstly. Then this obtained bridging tensor was used to deduce analytical formulae for all the 5 effective elastic moduli of the composite made with the transversely isotropic matrix. An extension of the bridging model applicable to fiber reinforced transversely isotropic matrix composites was achieved as well. With properly chosen bridging parameters, the predicted elastic moduli of the composite with the 2 models are quite close to each other.