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Improving the strength and lateral stiffness values of the reinforced concrete structure can be done by installing the brick wall. The capacity of the reinforced concrete structure cannot be predicted if the wall equipped with openings. Developing the modeling using the diagonal strut method was done in this analytical model for wall with openings in this research. The analytical modeling results will be verified with experimental and analytical models of brick walls with two openings and a door opening show comprehensible results with deviations of 19% and 7.9% for IFOW1, IFOP and IFOW2, respectively. In other words, the analytical equations developed are successfully applied.

Rankine's theory stated that the soil failure plane behind the monolith retaining wall is a linear equation and is applied similarly to the plane of precast block retaining walls. However, the actual failure plane in the field may differ from the theory. This research is done to determine the plane of soil failure behind a precast block retaining wall using wall modeling tests in the laboratory. Several stages for laboratory tests are carried out. Starting with making a precast block retaining wall with the planned dimensions, then a failure test is carried out by giving variations and adding loads in stages. The plane and pattern of failure from recorded laboratory tests. The failure shape is analyzed to obtain the mathematical equation. The shape of the failure obtained from the analysis is in the form of an S curve, with a power three polynomial function. Furthermore, the total area of the failure land is calculated. When compared with the results of the analysis using Rankine's theory equation, it is found that the area of the failure soil from the laboratory test of the precast block retaining wall is smaller, while the length of the failure of the soil is longer. The altitude simulation is continued based on the obtained mathematical model.

A simple and accurate analytical model for defining the lateral strength of the multi-span RC frame with masonry infill has been developed in this study. This model is developed due to the limitation of the current analytical model which only can be applied to the single-span RC frame. Meanwhile, the structure in the building also is in a multi-span frame and masonry infill greatly impacts the portal structure. In the existing building, this analytical method is needed to calculate the lateral strength of the RC frame. Besides, the analytical method was developed based on the lateral strength analysis method of a single-span RC frame in which the modeling of a multi-span RC frame with masonry infill along with uniform span spacing was applied. Furthermore, an equivalent diagonal strut with the same thickness and material as the masonry panels was used instead of masonry infill in the frame structure. The external column has diagonal compressive forces on the top or bottom of the column. On the other hand, diagonal compressive forces work at the top and the bottom of the column in the internal column. The lateral strength of the infill was determined based on the frame infill contact length. Furthermore, in order to obtain the lateral strength of the structure, the experimental study of a multi-span RC frame with masonry infill under cyclic load was also tested. Applying the analytical model has shown promising results even after being compared with the results of the experimental work.

The seismic performance of a bridge can be shown by analyzing the vulnerability of the structure in resisting an earthquake motion and then developing into fragility curves. This study presents a convenient method to establish the fragility curve for the cable-stayed bridge. For this purpose, three spans cable-stayed bridge is assessed using a series of seismic loads in different intensities to ensure that the structure was experiencing damage in several conditions. The fragility curve was obtained by analyzing the structure using Nonlinear Time History (NTHA) and Pushover Analysis. The ground motions of the earthquake were subjected to the bridge in different intensities, which were scaled from the initial ground motion. Hereafter, the structure’s ductilities were developed into the fragility curves as the responses of the bridge. HAZUS standard is used for classifying the damages of the bridge, which are grouped into; slight, moderate, extensive, and complete due to the seismic load. The values of the damage states were generated to the fragility curves using the probabilistic values of the damage states. To ensure the validity of the data statistically, Kolmogorov-Smirnov test was conducted to the fragility function. The result revealed that the fragility curve was qualified as the lognormal distribution.

This study conducts a preliminary investigation to determine the material properties of Cross- Laminated Timber (CLT) made from the bark of unproductive palm trunks. One-third of the lower part of palm trunks, aged over 20 years, was used for this purpose. CLTs were created by laminating palm boards into three and five layers, each measuring 200 mm x 20 mm x 1500 mm. A chemical epoxy was employed for lamination. The palm stems were dried in an oven at 110°C for 24 hours. Test results revealed a water content of 6.79% and a specific gravity of 0.23 gr/cm3 in oil palm stems. According to ASTM D143-94- 2005 and JIS Z210-21118 standards, wood's acceptable moisture content ranges from 12% to 20%. Given its low specific weight and minimal water content, palm oil trunks, including infill walls, show promise for use in earthquake-resistant construction.

A concrete block retaining wall is supported by its weight. This block retaining wall structure has some advantages, including lower construction costs, a water-permeable construction that produces less water pressure behind the wall, and a more flexible construction because it can follow the ground's contours. Rankine's theory is usually used to design this block retaining wall. According to this theory, the failure pattern behind the wall forms an angle of 450 + • /2 with the horizontal plane. The laboratory tests indicate that the pattern of failure or the pattern of sand movement behind the wall is similar to the letter S. From the sandy soil of failure pattern curve, look for a functional equation approximating the pattern. The equation of the function obtained is an equation of the third-order function. An analysis of the sliding, overturning, and overall stability block retaining wall is based on this equation of the cube function. Analysis for overall stability using the method of slices, dividing the failure area by several slices. These function equation order three is needed to get the area and length failure.

This paper presents the evaluation of the seismic performance of brick infilled RC frame structures with bed joint reinforcements based on reversed cyclic lateral load tests. Three specimens of the structural model of 1/4 scale-down single-story single-bay brick infilled RC frame was prepared, which were brick infilled RC frames with and without bed joint reinforcements. Two specimens of brick infills with bed joint reinforcements were different in the spacing of bed joint rebars. The specimens were tested by applying a reversed cyclic lateral loading in-plane direction. During the tests, the crack propagation was observed at the peak and residual drifts of each loading cycle to recognize the failure mechanisms of the specimens. As the results, although the use of the bed joint reinforcements ineffective to increase the lateral strength of the overall infilled frame structure. The rebars in mortar bed joints role to sustain the lateral strength in plastic deformation, and provide the whole structure with high ductility. It seemed that the rebars in mortar bed joints confined the brick infills. Therefore, the infilled RC frames can survive in large deformation without failure of the infills in out of the plane direction.

This study focuses on the experimental works to define the behavior of the reinforced concrete (R/C) frame model with the strengthening of the brick masonry infill by using the embedded reinforcement bars subjected to lateral reversed cyclic loads. A previous study by applying the lateral monotonic static loads showed that the embedded reinforcement bars increased the lateral capacity of the R/C frame and also delayed the failure of the brick masonry infill and R/C frame structure as well. However, in order to define its seismic capacity, a lateral reversed cyclic loading is required. The experimental works in this study were conducted by preparing and testing the 1/4 scaled-down R/C frame specimens represented the first story of the middle multi-story commonly constructed in the earthquake-prone area such as West Sumatera, Indonesia. The R/C frame specimens were two R/C frames with brick masonry infills where one of them strengthened by the embedded reinforced bars. All specimens were tested for applying the lateral reversed cyclic loads. The applied lateral load, the lateral displacement, the progressive cracks, and the failure mode of the specimens were observed and recorded during experimental works. As it was expected, the presence of the embedded reinforced bars in the brick masonry infills increases the seismic capacity and stiffness of the R/C specimens and also delayed the failure of the specimens. The experimental results in this study imply the simple strengthening method for the brick masonry infills.

This paper will describe the seismic behaviour of masonry infilled RC frame with a central opening structure under reversed cyclic lateral loading. To achieve the purpose of this study, four 1/4-scale single story and single bay RC frame specimens were tested, i.e. one bare frame, one clay brick masonry infilled RC frame without opening and two clay brick masonry infills with a central opening in infills. The ratios of opening size to panel area were 25% and 40%. Through reversed cyclic lateral loading tests, the seismic performance of RC frames with a central opening brick masonry infills was investigated. As the results, significant distinctions of failure mechanism, lateral strength, stiffness, and ductility were observed between these specimens. In the case of infills with a central opening, the cracks sprouted and developed at the corners of the opening. Although the presence of the opening in infill reduces the lateral strength and stiffness overall structure, the brick infilled frames with a central opening of 25% and 40% of panel area show better seismic performance as compared to the bare frame.

Since a long time ago, Padang City has been recognized as one in most-earthquake and tsunami prone city in the world. The successive significant earthquakes that have struck western coast of Sumatra Island from 2004 to 2010 seems to warn the city about its prone condition. The last major Padang-Pariaman earthquake on September 30, 2009, for instance, has caused hundreds of death and lousy damage to thousands of houses and buildings in city. Recently, several new multistory reinforced concrete (RC) buildings have been established in this area. Its include such buildings as government office, mosques, hotels, school and university. The city government plans to use these buildings as vertical evacuation facilities if an earthquake followed by a tsunami hit the city in the near-future. As a consequence, of course, these infrastructures should be well designed and constructed to resist the future earthquakes motion. This paper discusses an evaluation of the seismic performance of an existing multistory RC building in Padang city. The building was a ten-story of hotel RC building located near the coastline of Padang city. A series Pushover and Time History Analyses were conducted to examine the seismic performance of the target R/C building. It uses STructural Earthquake Response Analysis (STERA-3D), a computer software based on the nonlinear finite element method. The Pushover analysis was conducted for maximum drift ratio 1/200 in X and Y directions, respectively. The input ground motion in a maximum acceleration of about 400 gals and 600 gals for 60 seconds’ excitation were used for the Time History Analysis. These input ground motions were generated from the recorded ground motion of 2009 Padang-Pariaman earthquake. The result of the analyses suggest that the current target multistory RC building has outstanding seismic performance. The result is based on the level of damage of the structural components, base shear, inter-story drift, lateral displacement, dynamic responses and the seismic capacity spectrum of the analytical model.

Many researchers have performed a lot of studies of the seismic behavior reinforced concrete (RC) frame with masonry infill. They found that masonry infill affects the lateral strength, stiffness and ductility performance of the RC frame structures. However, when openings appeared in the panel infill for door and windows, the responses of the overall structure are entirely changed. The primary purpose of this study is to experimentally investigate the behavior of brick infilled RC frames possessing single opening and two openings. Four specimens of 1/4-scale single bay RC frames with brick infills were made that were one bare frame, one frame with full infill and two frames with infills having a central opening and two openings with the opening ratio of 25%. The specimens were tested under lateral reversed cyclic loads. Consequently, different responses of failure mechanism, lateral strength, stiffness and energy dissipated were observed among the specimens. The brick full infill failed in shear with propagation cracks in central part of the panel, but in the case of the infills with single and two openings, the cracks were dominated at the corners of the openings. The in-plane strength, stiffness and dissipated energy of infilled frames decreased when openings appeared in the panel. However, the seismic performance of brick infilled frame with the opening of 25% of panel area is better than those of bare frame. The brick infilled frames with a central opening and two openings are similar in lateral strength and dissipated energy. It seems that area and position of the openings control the seismic response to the overall infilled frame structure of the openings

The suspension footbridges are commonly constructed in the rural area. The constructions method is relatively simple compared to other types of bridges, thus as consequence, the construction cost also becomes relatively cheaper. Therefore, the community-based construction may be applied to construct its type of the suspension footbridges. Unfortunately, due to their long span, slender and moderate weight, the footbridge construction has excessive vibration caused by the induce moving load such as pedestrian and motorcycle movements. This condition, however, will seriously unsafe when the footbridges are used for tsunami evacuating to the safe zone, such as in Padang city area. In this study, a simple Tuned Mass Damper (TMD) is proposed to reduce such kind of excessive vibration of the suspension footbridge mentioned above. The TMD is composed of the mass concrete and used the motorcycle or light car spring. The dynamic analysis by using the computer code based on the finite element method has shown the promising results. The excessive vibration of the analytical model of the suspension footbridge is significantly reduced. Its reduction is shown by the reduction of the vertical deformation of the suspension footbridge up to more than 90% compared to suspension footbridge without TMD. The type of suspension footbridge which using the current proposed TMD is recommended to be used in the tsunami-prone area such as for Batang Arau in Padang city.

On September 28, 2018, Palu city in the Central Sulawesi area, suffered the M7.5 earthquake. An epicenter of its earthquake located 77 km from the capital of Central Sulawesi Province, Palu city. The main earthquake, followed by a localized 4 to 7 meters high tsunami, which swept shore-lying houses and buildings on its way. A large number of damages on reinforced concrete (RC) buildings, houses, and soil liquefaction spread in Palu city were observed after the earthquake. The post-earthquake observation, as is reported in this paper, was conducted in order to define the typical pattern of the buildings' damages. The field investigation was focused on the damaged RC frame of buildings' structures. Several types of damage were detected on RC structures such as collapse due to the soft story, damage to beam-column joint, failure of short column, shear failure of the column, and collapsed of brick masonry infills. Two damaged RC frame buildings, i.e., one was severely damaged and the other in totally collapsed, were furthermore analyzed to define their seismic capacity based on Japanese standard. According to the analyses of the first story in these buildings, the distinct difference of seismic performance of both buildings was discovered. The severely damaged building had a higher lateral strength index when compared to the collapsed building because of its structure able to maintain the lateral strength within large deformation. [ABSTRACT FROM AUTHOR]