Suprapto Siswosukarto

Stability Analysis of variation Span and Turning Angle against Width in suspension bridge

One of the critical issues for a long suspension bridge is the vibration induced by wind. The excessive vibration on long suspension bridge owing to bridge flexibility may cause the bridge’s aerodynamic instability and vehicle accidents. Therefore, in the present study, the optimum ratio for the span and turning angle to bridge width was investigated. The analysis was carried out on bridge with total span of 470m, main span 270m and side span 100m, using variations of bridges width ranging from 9m to 22m. SAP2000 program was used to analyze the stability behavior of the suspension bridge under wind load at speed of 35m/s. The results of analysis shows that the optimum ratio of span to width bridge is 0.034L or L= 29.375b. When the turning angle was taken into consideration in the analysis, it will result in increasing the bridge’s stability, decreasing natural frequency of the structure and increasing stresses on the cables. Further, it was also found that the deflection and the internal forces on the girder meet the specified limits by AASHTO and AISC standard specification. Keywords—suspension bridge, wind, vibration, stability analysis, turning angle

Experimental and Theoretical Investigation of Bolted Bamboo Joints without Void Filled Material

An experimental and theoretical are presented to calculate the load capacity of shear single connection (SSC) and shear double connection (SDC) without void filled material. The model presents an extension of the Johansen theory for bamboo connection type, also known as the European Yield Model (EYM). The bamboo of Gigantchloa atroviolacea of the most popular as non-wood has been used as a construction material in some region of Indonesia. The uniqueness bamboo is bamboo non-homogen material, sectional shape non-prismatic, the straighthness stems not same, on the culms guiler node and a cross-section in hollow. The diameter of Gigantochloa atroviolacea bamboo used in this study is ranged from 70 to 90 mm. The diameter of bolt is 12.7 mm. The connection strength can be determined with theoretical and eksperimental. Application theory of the European Yield Model could be developed into theory of connection laterally strength of bamboo without void filler material. Factors that affected of connection laterally strength is bamboo thickness, bolt diameter and spesific gravity. The equation four of connection strength base on European Yield model can calculated of according to yield model of accurred. The connection strength is specified from the value smallest of the equation four of connection yield models.

The Effect of Variable Lateral Stress of Laminated Bamboo with Artificially Dent Surface on Mechanical Properties

Since many years ago bamboo has been used, in addition to wood, for structural components in rural areas due to easily growth and its short harvest time. The properties of laminated bamboo depend on many aspects, among others: quality of glue, lateral stresses during manufacture and roughness of bamboo lamina. This research used Bambusa Dendrocalamus Asper (local name: Bambu Petung) and aimed to determine the effect of artificial dented surface of the laminas on mechanical properties with variable lateral stresses. The dimensions and the types of the specimen were based on ISO 2004 standard. The age of bamboo specimens was 6 years and the lateral stresses were varied from 0 MPa to 2.5 MPa with 0.5 MPa interval. Physical properties of the specimen such as water content (humidity), specific gravity, were performed prior to the mechanical tests (tensile, compression, shear and flexural tests). Analysis of results was performed by statistical method, in addition to scanning electron microscopy for further inspection of microscopic deterioration.