This dissertation examines how structural discontinuities affect the mechanical properties of composite beams reinforced with glass fibers. The study explicitly classifies these discontinuities as inter-ply or intra-ply based on discontinuity types within the composite layers. Discontinuities were introduced as pre-curing. The mechanical properties of these samples were evaluated using servo-hydraulic actuators in three-point bending quasi-static tests. The experimental results were compared to the predictions of CAE analysis by assessing the sectional fiber volume fraction and further complemented with microscopic analysis of local discontinuities. The study found that areas of dislocation lead to zones with a high concentration of resin, and the exothermic curing process causes increased temperatures. As a result, the resin changes color from clear to yellow, indicating decreased mechanical durability. Fiber discontinuities and resin gaps weaken the structural integrity of glass fiberreinforced polymer (GFRP) composite leaf springs. Irregularities in manufacturing, whether between layers or within a single layer, can impact the durability of the material and its ability to fill gaps. The findings highlight the significance of material composition, structural integrity, and comprehension of failure mechanisms in the design and production of composite beams. It is essential to address heat transfer concerns to reduce resin gaps and prevent fractures caused by heat. The results indicate that understanding the relationship between internal structural flaws and gaps in the resin can greatly improve the design and production of beams. This study offers crucial insights for enhancing composite materials' structural performance and dependability in engineering applications..