A series of small-scale rectangular reinforced concrete beams made with different mix proportions were presented. The beams were fabricated using normal concrete designated as specimen control (NC), normal concrete blended with supplementary material using Class F fly ash (SMFA), and engineered cementitious composite (ECC). The beams comprised of similar reinforcement where the ratio of compression, tension, and transverse bars were 1.0%, 1.5%, and 1.0% respectively. To this end, the beams were tested under four-point bending and they were intended to fail in flexure mode. The tests also aimed to provide direct evidence regarding the improvement of beam ductility due to the use of ECC. Furthermore, the performance of test beams on the overall strength, crack pattern, and damage state was also assessed. To corroborate the experimental work, an analytical work employing nonlinear finite element analysis using Abaqus was also included. From this study, it was found that each beam demonstrated a discernible ductile plateau upon the post-cracking region with Beam ECC showing the largest ductility compared to the other two thereby suggesting that the use of ECC could enhance the beam ductility. It was also shown that the flexural cracks manifested in Beam ECC were less critical, signifying that ECC is a damage-tolerant composite. Furthermore, the overall results of predicted load-deflection and damage state obtained from Abaqus were also in a good agreement with the experimental results.

The application of high strength material is used to limit the width of the column under the floor of a high-rise building. High strength concrete column specimens with dimensions of 600x600x1800 mm will be modeled using the ABAQUS program with constant axial load and lateral displacement. High strength concrete specifications 70 MPa, high strength longitudinal reinforcing bar (SD685) and high strength transverse reinforcing bar (SD785) were used in this study. The constant axial load input used is 0.1Agf'c with the lateral displacement load until it fails. The purpose of this study was to determine the behavior of force-displacement relationship of high strength reinforced concrete columns that occurred due to the monotonic lateral displacement load and low axial load. Modelling of concrete elements using solid CD38R and reinforcig bar using T2D3 truss elements with mesh 100x100 mm. High strength concrete column modeling results show that the prediction of FEA high quality concrete columns has a good correlation with the experimental results for column stiffness.Kata kunci: Kolom mutu tinggi, beban aksial, pemodelan, elemen hingga Abstrak Penerapan material mutu tinggi mulai digunakan untuk membatasi luas kolom dilantai bawah struktur gedung tinggi. Spesimen kolom beton mutu tinggi dengan dimensi 600x600x1800 mm akan dimodelkan menggunakan program bantu ABAQUS dengan beban aksial secara konstan dan lateral displacement. Spesifikasi beton mutu tinggi 70 MPa, tulangan longitudinal mutu tinggi (SD685) dan tulangan transversal mutu tinggi (SD785) digunakan pada penelitian ini. Input beban aksial konstan yang digunakan adalah 0,1Agf'cdengan beban lateral displacement sampai gagal. Tujuan penelitian ini adalah untuk mengetahui perilaku hubungan force terhadap displacement kolom beton bertulang mutu tinggi yang terjadi akibat beban perpindahanlateral monotonik dan beban aksial rendah. Pemodelan elemen beton menggunakan solid CD38R dan tulangan menggunakan elemen truss T2D3 dengan mesh 100x100 mm. Hasil pemodelan kolom beton mutu tinggi menunjukkan bahwa prediksi FEA kolom beton mutu tinggi mempunyai korelasi yang baik dengan hasil eksperimen untuk kekakuan kolom.

Concrete's durability is the key factor that affects the service life of the concrete structure. One factor that affects the durability properties of concrete is its pore structure, which can be investigated by analyzing the materials' absorption rate. For the structures with direct contact with water, water absorption can change the pore structure's behavior, affecting the durability of the conc in the long term rate. It is important to research to find the water absorption properties of concrete with different mixtures.This research investigates the rate of absorption of concrete by using fly ash and silica fume. Based on secondary absorption properties, the result shows that 15% fly ash in normal concrete increases the resistance to water penetration by 23%. The usage of 5% Silica Fume increases the resistance by 11.8%. The usage of 5% silica fume + 10% fly ash increases the resistance by 16.2%. It shows that the use of supplementary materials in concrete increases the resistance of water penetration. In this research, the usage of 15% fly ash as cement replacement shows the best result.

This article presents about vulnerability assessment of high-rise building in Surabaya, the second largest city in Indonesia. In 2007, the Earthquake National Research Center -Indonesia’s Ministry of Public Works released the latest earthquake fault map. Include the discovery of Surabaya fault and Waru fault that across Surabaya. According to that new discovered fault, it is possible that there is a higher potential earthquake hazard for buildings structures in Surabaya. Therefore, the efforts to assess the vulnerability of buildings towards the earthquake need to be conducted, especially for the high-rise buildings. An android based RViSITS (Rapid Visual Survey by Institut Teknologi Sepuluh Nopember) is an application that has been developed based on FEMA 154. That application helps the vulnerability assessments of buildings can be conducted quickly and efficiently. Since, it does not require a lot of personnel, quite short research time and cheaper cost than having to use a manual form that is considered less effective for a large number of buildings. This research itself is conducted to assess the vulnerability of high-rise buildings (8-15 floors) throughout Surabaya city using the RViSITS android application. Based on the results of this study on 98 high rise buildings, it is found that 21 buildings (21.43%) are in the prone category since they had an index value < 2, while 77 buildings (78.57%) are in the safe category with an index ≥ 2. The result obtained in this research can be used as a database of local government institution for mapping the vulnerability of high rise buildings and initial input for mitigation plan toward the higher possibility of an earthquake hazard in Surabaya.

In 2017, Indonesia’s National Earthquake Study Center (PuSGeN) issued an updated Indonesian sources and potentials of earthquake map which shows the possibility of new earthquake hazards potentials. This triggers the assessment of building’s vulnerability towards that new earthquake hazard potential. The assessment of building vulnerability towards earthquakes is divided into two types; quick check using Rapid Visual Screening (RVS) and thorough check. In its development, RVS method was chosen because it does not require a lot of personnel, reduce time for survey, and requires lower research costs. However, RVS method that uses manual form is considered less effective for buildings with a large numbers. Nevertheless, with the existence of RViSITS android application which has developed by ITS’s RVS Team based on FEMA 154, the assessment of building vulnerability and the result can be done and accessed by all sectors quickly and easily. This article aimed to assess the vulnerability level of three high-rise buildings (8-15 floors) in East Java using RViSITS android application by comparing the result of numerical analysis based on earthquake regulations applicable in Indonesia according to SNI 1726:2012. The result of analysis using RViSITS showed that the level of vulnerability of three high-rise buildings studied is “qualified” or earthquake safe. Based on numerical analysis, it shows that the control result of base shear, mass participations, structure periods and driff control are appropriate as required by SNI 1726:2012. Generally, RViSITS can be used to map the vulnerability of high-rise buildings throughout the region in Indonesia.