Fiberglass-Enhanced Cement Slurry: Achieving Peak Compressive Strength and Loss Circulation Mitigation

ABSTRACT The oil and gas industry routinely faces cement integrity challenges in high-pressure, high-temperature (HPHT) wells, including strength retrogression and loss circulation. This study introduces fiberglass as a novel, multifunctional additive to enhance both compressive strength and loss circulation mitigation in Class G cement slurries. Unlike conventional solutions requiring multiple costly additives, fiberglass provides a dual advantage by reinforcing the cement matrix against thermal degradation while simultaneously forming a physical barrier that reduces fluid loss. The experimental program involved formulating and testing fiberglass-reinforced cement slurries under simulated HPHT conditions of 120 °C and 8,000 psi for 76 hours, using an Ultrasonic Cement Analyzer (UCA) and a High-Pressure High-Temperature Filter Press. Results demonstrated a compressive strength of 2,570 psi reached in under 22 hours, which remained stable throughout the 76-hour test—eliminating the strength retrogression typically observed in unmodified slurries. Additionally, the fiberglass-enhanced slurry reduced fluid loss by 68.89%, compared to conventional cement systems. Microscopic evaluations confirmed that uniformly dispersed fiberglass fibers create an interlocking network within the cement matrix, thereby improving fracture sealing and minimizing filtrate escape. These findings establish fiberglass-enhanced cement as a technically viable and cost-effective alternative to conventional high-temperature additives. The novelty lies in combining strength enhancement and loss circulation control into a single, simple additive strategy, substantially lowering operational risks and reducing non-productive time (NPT). This study concludes that fiberglass technology presents a transformational approach for the oil and gas industry, offering improved well integrity and extended service life for HPHT wells, with potential for broader applications across diverse reservoir environments.