A 3D finite element analysis was carried out to study the behavior of slab-column connections in a flat slab structure under combined gravity and cyclic lateral load. Prior to simulating the behavior of the proposed model, the slab-column connection specimen by using standard orthogonal stud rail from the previous study was modeled with the purpose of verifying the results using finite element tool. Given that numerical simulation was undertaken using ABAQUS to predict the structural behavior of the above-mentioned structure. With regard to providing an accurate result, a sensitivity analysis was performed by changing different parameters, such as dilation angle, viscosity parameter, and damage parameter-strain on both in tension and compression. After gaining the close resemblance to the previous study, the proposed models were then simulated using the similar technique. In the proposed model, drop panel element was used as a replacement of stud rail. Additionally, the engineered cementitious composite material using polyvinyl alcohol fibers (PVA-ECC) was also employed due to its strain capacity of 3-5% under tension compared to 0.01% of conventional concrete. Through this study, the results showed that the effect of utilizing the PVA-ECC material could significantly improve the specimen behavior and damage tolerance.

This research investigates the effect of the presence of infilling concrete inside of the middle void of the spun pile on its flexural behavior. The flexural monotonic load without axial load testing was conducted on the full-scale of two spun piles with infilling concrete. The dimensions of the pile were 400 mm in diameter, 75 mm in wall thickness, and 6,000 mm in length. The compressive strength of the concrete of the spun pile and infilling concrete was 58.4 MPa and 26.9 MPa, respectively. The observed flexural behaviors were the moment capacity, displacement ductility factor, and failure modes. Comparing with the previous research result about the testing of the spun pile without infilling concrete, the present testing results show that the presence of infilling concrete as the core of the spun pile’s section did not have a significant effect on the flexural performances of tested spun pile. Low compressive stress on compression fiber, due to no axial load, caused no concrete crushing occurred and the confinement mechanism of spiral reinforcement did not work. The fracture of the PC bar on extreme tensile fiber become the trigger of the failure of the pile. All piles had a ductility factor around µ∆ = 4 in all cases. According to the seismic design code requirement, the spun piles were appropriate to be applied to a moderate seismic risk area. In application, due to seismic load, the piles should be designed remaining in the elastic state.

This paper presents nonlinear finite element analysis of eccentrically loaded circular Reinforced Concrete (RC) column confined with Carbon Fiber Reinforced Polymer (CFRP) wraps. The concrete constitutive model uses a plasticityfracture model which is restraint sensitive, utilize a non-constant plastic dilation rate, and is able to simulate the plastic volumetric compaction of concrete core under high confining pressure. For validation of the models, two available specimens from the literature are used in the validations. Excellent agreement between the numerical models and the available test results are obtained in this study. A detailed investigation on the confinement effectiveness of both external and internal confining devices are presented and discussed. This discussion of the confinement effectiveness is important to be included in the design formula.

The use of Reinforced Concrete (RC) deep beams in the building may require web openings or holes for electrical and mechanical utility passage. This web opening will change the behavior of the RC deep beam and may result in early cracks even at service load. Hence, it is important to use a suitable tool to predict the full response of the RC deep beam with the opening. For that purpose, a nonlinear finite element method using 3D-NLFEA software package which utilizes a plasticityfracture model is used to predict the behavior of RC deep beam. One deep beam specimen available in the literature is investigated. To study the effect of using structured and unstructured mesh, as well as different element types on the loaddeflection curve, the hexahedral and tetrahedral solid element was used. From the comparisons, it was observed that the crack pattern between two different meshes was not similar. Structured mesh often has straighter crack propagation compared to the unstructured mesh. The load-deflection curve for both models is similar and both models were performed satisfactorily in predicting the peak load of the deep beam.

Base isolation merupakan salah satu alat peredam gempa yang banyak digunakan pada dunia konstruksi, salah satunya pada Gedung J-Tos Jogjakarta. Pada studi ini akan dianalisis kinerja gedung tersebut dengan melakukan perencanaan gempa pada daerah gempa kecil kemudian hasil analisys tersebut digunakan untuk mendesain bagunan pada daerah gempa kuat dengan menambahkan base isolation tipe high damping rubber bearing (HDRB) pada dasar bangunan selanjutnya dilakukan analisis pushover. Gedung dimodifikasi pada jumlah lantainya yang sebelumnya 6 lantai menjadi 8 lantai. Dari hasil perhitungan analisis struktur. Displacement pada gedung yang menggunakan HDRB lebih besar dari pada gedung yang menggunakan sistem fixed-base yaitu akibat beban gempa dinamik displacement meningkat 66,97% untuk arah x dan 57,53% untuk arah y, Simpangan antar lantai (Δ) pada gedung yang menggunakan HDRB lebih kecil dari pada gedung yang menggunakan sistem fixed-base yaitu akibat beban gempa dinamik Δrata-rata tereduksi 82,52% untuk arah x dan 78,08% untuk arah y, Dari hasil analisis pushover, level kinerja gedung denganisolasi berdasarkan ATC-40, FEMA 356 dan FEMA 400 adalah B (Operational). Kata Kunci-Analisis pushover, base isolator, high damping rubber bearing, level kinerja struktur.