Local Material Samboja Sand in East Kalimantan: Utilization with Fiber Reinforced Polymer Jacketing as an Effort to Increase the Concrete Strength. JTT (Jurnal Teknologi Terpadu), [S. l.], v. 3, n. 2, 2015. DOI: 10.32487/jtt.v3i2.90. Disponível em: http://jurnal.poltekba.ac.id/index.php/jtt/article/view/90. Acesso em: 8 jun. 2026.