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) [Internet]. 2015 Oct. 12 [cited 2026 Jun. 8];3(2). Available from: http://jurnal.poltekba.ac.id/index.php/jtt/article/view/90