Electronic Theses and Dissertation

Beton merupakan material utama dalam kontruksi bangunan yang memiliki kuat tekan tinggi, namun lemah terhadap gaya tarik sehingga mudah mengalami retak saat menerima beban lentur. Penelitian ini bertujuan untuk menganalisis pengaruh penambahan jumlah lapisan serat terhadap perilaku lentur balok beton bertulang yang ditinjau dari kapasitas beban maksimum, lendutan, dan pola retak. Benda uji terdiri dari balok kontrol (BLK), balok serat 2 lapis (BL2L), balok serat 3 lapis (BL3L), dan balok serat 4 lapis (BL4L) yang diuji dengan pembebanan bertahap hingga mencapai kondisi maksimum. Hasil penelitian menunjukkan bahwa kapasitas beban maksimum balok meningkat seiring dengan bertambahnya jumlah lapisan serat, di mana balok BLK mencapai beban maksimum sebesar 99,44 kN, sedangkan balok BL2L, BL3L, dan BL4L masing-masing mencapai 116,91 kN, 118,60 kN, dan 117,62 kN. Retak lentur awal berupa retak lentur muncul di daerah tengah bentang, kemudian berkembang seiring peningkatan beban dan diikuti oleh retak diagonal di daerah tumpuan, Dengan demikian, penambahan jumlah lapisan serat terbukti mampu meningkatkan kapasitas lentur balok beton bertulang serta mengendalikan perkembangan retak dibandingkan balok tanpa serat.

Kata kunci: balok beton bertulang, perkuatan serat, jumlah lapisan serat, kapasitas lentur, pola retak

Concrete is the main material in building construction that has high compressive strength, but is weak against tensile forces so it is easily cracked when receiving bending loads. This study aims to analyze the effect of increasing the number of fiber layers on the flexural behavior of reinforced concrete beams in terms of maximum load capacity, deflection, and crack patterns. The test specimens consisted of a control beam (BLK), a 2 layer fiber beam (BL2L), a 3 layer fiber beam (BL3L), and a 4 layer fiber beam (BL4L) which were tested with gradual loading until reaching the maximum condition. The results showed that the maximum load capacity of the beam increased with increasing the number of fiber layers, where the BLK beam reached a maximum load of 99.44 kN, while the BL2L, BL3L, and BL4L beams reached 116.91 kN, 118.60 kN, and 117.62 kN, respectively. Initial flexural cracks in the form of flexural cracks appear in the mid-span area, then develop as the load increases and are followed by diagonal cracks in the support area. Thus, increasing the number of fiber layers is proven to be able to increase the flexural capacity of reinforced concrete beams and control crack development compared to beams without fibers. Keywords: reinforced concrete beams, fiber reinforcement, number of fiber layers, flexural capacity, crack pattern