The Landau-de Gennes type continuous model is used to describe the 2D modulated structures made of bent-core liquid crystals. It is shown that modulation is a direct consequence of the chiral symmetry breaking. Structures with synclinic and anticlinic layer tilt are found to coexist in the polarization modulated and layer undulated (PM-LU) liquid crystal phase. The synclinic PM-LU structure corresponds to the columnar B(1RevTilted) phase. Experimentally obtained electron density maps are included, which support theoretical findings.