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Chloride ingress is one of the major causes of durability problems in reinforced concrete structures. This research focused to investigate the chloride penetration process through the concrete subjected to wetting and drying cycle. This research used 150 x 150 mm normal concrete prism sample with a 40 mm concrete cover. Three wetting and drying configurations used in this study to investigate the effect of wetting and drying period to the chloride penetration. The result indicated that the chloride concentration and penetration depth were highly influenced by the duration of wetting and drying. Based on the experimental result, concrete exposed to 5 hours drying and 3 hours wetting has the highest chloride concentration compared with the sample exposed to other wetting and drying configuration.

Expansion of rust, as a result of reinforcement corrosion, can cause additional internal expansive pressure and initiate cracking to the concrete. This paper presents experimental test and numerical modeling of concrete cracking induced by reinforcement corrosion. The simulation was performed using finite element based program Abaqus CAE using concrete smeared cracking approach. The numerical modeling used non-uniform and uniform corrosion assumption to get more accurate result. Based on the result, the numerical modeling has 3.01% lower stress than the experimental test. The result of the simulation using non-uniform assumption showed more similar cracking pattern with the experimental test compared with uniform assumption.

This paper investigates the possibility of using a multi-surface plasticity model to predict shear failure in reinforced concrete beams. The analysis is carried out using the in-house software called 3D-NLFEA. The constitutive model for the concrete material is based on the plasticity-fracture model, which had previously developed to simulate the behavior of concrete cover spalling in reinforced concrete columns.To obtain the asymmetric shear failure pattern, random material properties imperfection for each meshed element is used. Two beams available in the literature are investigated and compared with the analysis results using 3D-NLFEA. From the comparisons, excellent agreement between the analysis and the test result was obtained. 3D-NLFEA can predict the peak load accurately. The peak load prediction only varies 2.19% for beam OA1 and 3.28 % for beam OA2, and it was lower than the test results. The failure crack patterns also show a typical diagonal crack extension from the support to the loading steel plate.

Examination of vulnerability level of buildings to earthquakes is divided into two types, the quick checks (Rapid Visual Screening, RVS) and a thorough examination. On thorough examination, it involves specialists of the field of building structures and other related fields, takes longer and is also cost much more expensive. While a quick check, it does not involve many specialists in a particular area, does not require a long time and are relatively inexpensive. This study builds an assessment of the vulnerability of buildings quickly adapted from FEMA 154 to the conditions and rules that applied in Indonesia using a smartphone application. A Global Positioning System (GPS) technology is used to mark the location of the data of the examination. The smartphone application called RViSITS is used to simplify and speed up the examination process and sent via the internet, and the server as a gathering and processing data. Furthermore, from these data do building vulnerability mapping and disaster-affected areas, which can then be accessed by the public, government and private sectors as well as database information. In this research, the RViSITS application process is to apply the application to do a quick check on the buildings in Surabaya, so that later the database and mapping vulnerability condition of buildings owned by government institutions in Surabaya against earthquake loadings can be made. While in general, this application can be used any places, so that the database and mapping the vulnerability of buildings can be held any area in Indonesia.