Part of shear forces on reinforced concrete structures, will be borne by stirrup. According to Indonesia concrete standard, a closed stirrup must be used in earthquake prone areas. The end of the stirrups should be a hook with an angle ≥ 135°. The focus of this research is the modification of the hook shape on the stirrup reinforcement. This research is expected to design the shape of hook which good performance on shear holding. The basis of this research is experimental testing in the laboratory by cyclic loads. The specimens consisted of 2 pieces: TG1 and TG2. TG1 is a specimen with an angle135° end-hook shape according to SNI provisions. TG2 is a specimen with an angle 90° end-hook shape. The two specimens are reinforced concrete beams (250mm x 400mm x1700 mm). From the test, it is proofed that the two specimens are collapsed by shear. The ultimate load on the second specimen is greater than the ultimate load of first one, Pu1 = 245 kN and Pu2 = 270 kN. In addition, the deflection of the second specimen is greater than the deflection of the first one, δ1 = 12 mm and δ2 = 14 mm.

Saat ini, beton dengan menggunakan agregat ringan dapat mencapai kuat tekan 17 - 41 MPa. Di Cilacap terdapat industri penghasil agregat ringan yang mempunyai karakteristik material cocok untuk beton yaitu agregat ALWA Cilacap. Penelitian ini akan menggunakan agregat ALWA Cilacap untuk mensubtitusi agregat kasar pada beton sehingga dapat menghasilkan beton mutu tinggi yang ringan.  Metodologi yang digunakan dalam penelitian ini dengan melakukan eksperimen di laboratorium. Persentase penggunaan agregat ringan ALWA – Cilacap untuk mensubstitusi agregat kasar sebesar 0%, 5%, 10%, 15% dan 20%. Pengujian kuat tekan beton dan berat isi menggunakan benda uji silinder 150 x 300 mm.  Hasil penelitian menunjukkan bahwa kuat tekan beton maksimum pada benda uji B4 (subtitusi agregat ringan ALWA-Cilacap 15% dari agregat kasar) sebesar 39,7 MPa. Berat isi yang paling ringan adalah pada benda uji B5 (subtitusi agregat ringan ALWA-Cilacap 20% dari agregat kasar) yaitu sebesar 2.151 gr/cm3.

Reinforced concrete column strengthened with Carbon Fiber Reinforced Polymer (CFRP) has been investigated numerically. Reinforced concrete column with low compression strength is used in this study. Concrete column is modeled by 3D solid elements with 8 nodes linear brick elements (C3D8R), whereas reinforcement bars modeled by 3D truss elements with 2 nodes first order elements (T3D2). In order to simulate concrete response in the specimen, concrete damage plasticity model with specifying damage parameters in both of compression and tension has been adopted in this paper. The specimen is subjected to uniaxial compression loading applied with displacement-controlled method. The effects of CFRP jacketing on reinforced concrete column with low compression strength are observed. The characteristic of reinforced concrete column combined with CFRP in terms of load-displacement behaviour and stress distributions are also evaluated. It is found that the numerical technique proposed in this study is quite efficient to predict the behaviour of low strength reinforced concrete column strengthened with CFRP with regard to the ultimate load, CFRP strain, and concrete strain distribution.

Increasing capacity of structures can be done by various methods, one of them is by reinforcing on bridge structure.Reinforcement by using strand has been used on building construction but on reinforced concrete beams because of the problems on it’s execution. The focus of this research is how to install non-stressing strand as reinforcement material.The basic of the research is full-scalled loading test on structure laboratory. There are 2 loading test samples : a sample without reinforcement (Bo) and a sample with reinforcement(B1). The test specimen will be subjected to static monotonic loading until the collapse. The dimensions of the test specimen are 150 x 300 (mm) and the length of the span is 3200 mm.The result of loading for the reinforced concrete beam and reinforcement beam, the yield force value was 22 kN and 27 kN respectively, while deflection value was 9.5 mm and 13 mm respectively.Keywords: beam, reinforcement, strand without stressing, static load.ABSTRAKPeningkatan kemampuan(kapasitas) infrastruktur khususnya jembatan dapat dilakukan dengan berbagai metode, salah satu untuk meningkatkan kemampuan tersebut dengan memperkuat jembatan.Perkuatan menggunakan strand sudah digunakan pada berbagai konstruksi bangunan tetapi untuk balok beton bertulang belum banyak dilakukan karena akan mengalami kesulitan dalam metode pelaksanaan. Sehingga dalam penelitian ini akan mencoba menggunakan metode pemasangan strand tanpa penegangan sebagai bahan perkuatan.Penelitian dilakukan dengan cara pengujian eksperimental di laboratorium dan. Benda uji yang digunakan terdiri dari 2(dua) buah yaitu 1(satu) benda uji balok beton bertulang tanpa perkuatan(Bo) dan 1(satu) buah benda uji balok beton bertulang dengan perkuatan(B1). Benda uji akan dilakukan uji pembebanan statikmonotonik sampai mengalami keruntuhan. Dimensi benda uji 150 x 300 (mm) dan panjang bentang 3200 mm.Dari hasil pengujian terhadap balok beton tanpa perkuatan dan balok perkuatan didapatkan nilai gaya leleh berturut – turut sebesar 22kN dan 27kN serta lendutan berturut –turut sebesar 9.5 mm dan 13 mm.Kata kunci : balok, perkuatan, strand tanpa penegangan, beban statik