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As the need of the train speed increased, the existing bridges need to be evaluated, especially in dynamic responses, which are deformation and acceleration. In this study, Cisomang Bridge is modeled and analyzed due to the high-speed train SJ X2 in varying speeds, 50 km/h, 100 km/h, 150 km/h, and 200 km/h. The used of tuned mass damper also will be varied on its setting and placing. The tuned mass dampers setting be varied based on the first or second natural frequency and the placing of tuned mass damper be varied based on maximum deformation of the first or second mode. Moreover, the tuned mass damper ratio will be varied 1% and 1.6%. For all speed variations, dynamic responses of structure without TMD still fulfil the Indonesian Government Criterion based on PM 60 - 2012 but do not meet requirement of comfort criteria based on DIN-Fachbericht 101. Furthermore, only for the speed train 50km/h dynamic responses of structure fulfil safety criteria based on Eurocode EN 1990:2002, whereas the other speed variations do not meet that requirement. In the use of TMD 1% mass ratio, the structure fulfils the safety criteria for all speed variations. In the use of TMD 1.6% mass ratio, all the structure fulfils the safety and comfort criteria except 100 km/h speed which only fulfils the safety criteria.

Dieser Beitrag gilt dem Problemkreis “Abtragung von Längskräften auf Eisenbahnbrücken mit durchgehend geschweißtem Gleis”. Im Mittelpunkt stehen dabei die zusätzlichen Beanspruchungen zu den jahreszeitlichen Temperaturveränderungen, die sich bei der Zugüberfahrt infolge des Steifigkeitswechsels der Kopplung zwischen Gleis und Brückentragwerk ergeben. Dieses Phänomen wird zunächst an einem einfachen Ersatzsystem mit zwei Freiheitsgraden beschrieben und rechnerisch dargestellt.Statische und dynamische Parameterstudien an einem realitätsnäheren Gleis‐Tragwerk‐Modell zeigen die Entwicklung der Schienenlängsspannungen und horizontalen Brückenauflagerkraft für die Lastfolge jahreszeitlicher Temperaturwechsel – Biegung des Tragwerks – Wechsel der Koppelsteifigkeit unter Einbeziehung der Verformungsgeschichte.Longitudinal rail forces on railway bridges during passing of trains.This paper is devoted to the field of longitudinal forces on railway bridges with continuously welded rails. Here, the focus is placed on stresses additional to those from seasonal temperature change due to the sudden change of the coupling stiffness between track and bridge when a train is running along the bridge. This phenomenon is first explained and realized numerically by means of a simplified two degree of freedom system.Parameter studies, statically as well as dynamically, for a more realistic track‐bridge model demonstrate the development of the longitudinal rail stresses and the horizontal bridge‐support forces for the loading sequence seasonal temperature change – bending of the bridge – change of coupling stiffness with paying attention to the deformation history.

Comfort is one among several aspects in building design. Comfort of the occupant can be measured from the dynamic performance of the building during earthquake. This performance can be increased by installing vibration control to reduce dynamic responses of the building. Considering the space-use efficiency, the building is utilizing certain floors to act as mass dampers. The floors are able to move back and forth independently to counter building vibration. Utilizing an existing floor slab as a mass damper is known as passive vibration control or in particularly named self mass damper (SMD). A 14-story reinforced concrete building is modeled as a case study. The movable floor placement is varied in 3 configurations. The modeled building is excited by El Centro 1940 and Denpasar 1979 ground accelerations, independently. The study compares the dynamic responses of building without SMD and with SMD in three different placements. Placing SMD in 4 top floors (13th,12th, 11th, 10th) gives the best result in reducing building’s dynamic response compared to SMD in 4 mid-height floors (11th,10th, 8th, 7th) or separate group (13th, 12th, 6th, 5th). It is shown that the building has a tendency to response conforming 1st mode of the building. From the analysis, it can be concluded that applied SMD system gives greater reduction on building’s displacement, velocity, and acceleration in response to Denpasar ground acceleration rather than El Centro 1940.