Abstract: Liquid Core Reduction (LCR) technology, originally developed for thin slab continuous casting, makes it possible to secure the space for SEN in the mold while improving production efficiency. Recent experimental attempts have explored LCR implementation in regular slab casting processes. However, regular slabs (2-3 times thicker than thin slabs) face critical challenges: excessive deformation and stress concentration under external forces may induce intermediate cracks, currently preventing successful LCR adoption in regular slab production. This study evaluates LCR feasibility for regular slabs and identifies optimal reduction parameters to prevent crack initiation. A 3D thermal-mechanical coupled model is proposed using Finite Element Method (FEM), integrated with the Equivalent Replacement Liquid Steel (ERLS) method and the Normalized Cockcroft & Latham (NC&L) damage model, to achieve quantitative prediction of intermediate crack risk during the LCR process. The ERLS model was used to simulate the extrusion flow and expulsion behavior of the liquid core, and its accuracy was validated against actual production measurements. To identify the critical damage value leading to the initiation of intermediate cracks, this paper conducted a consistency analysis between high-temperature tensile tests and Finite Element simulations based on damage models. Based on this value, crack prediction was performed for Q355 slabs with cross-sectional dimensions of 170 mm × 1450 mm, resulting in the determination of an optimal reduction scheme: the second segment accounts for 50% of the total reduction, the third segment for 32.5%, and the fourth segment for 17.5%, with the theoretical maximum reduction being 34 mm. These results provide actionable guidelines for potential implementation of LCR in regular slab casting systems.