Joshi, Aditi S. M.S.M.E., Purdue University, May 2014. Study of Aluminum Honeycomb Sandwich Composite Structure for Increased Specific Damping. Major Professors: Dr. Douglas E. Adams and Dr. J. Stuart Bolton, School of Mechanical Engineering The aluminum honeycomb sandwich composite structure is commonly used in the aerospace and automotive applications where high strength to weight ratio is de...

The segmental prestressed concrete box girder of Koror-Babeldaob (KB) Bridge in Palau, which had the record span of 241 m (791 ft.), presents a striking paradigm of serviceability loss due to excessive multi-decade deflections. The data required for analysis have recently been released and are here exploited to show how the analysis and design could be improved. Erected segmentally in 1977, thi...

The bifurcation analysis of a composite beam subjected to harmonic flapwise base excitation is studied when the ratio of flapwise and chordwise internal resonances is 1:2. Results are obtained by the numerical solution of modulation equations. Chracteristics of the response are investigated in terms of time history, phase portraits diagrams and bifurcation diagram of poincare maps. It is observ...

This paper presents a method for modeling and analysis of cablestayed bridges under the action of moving vehicles. Accurate and efficient finite elements are used for modeling the bridge structure. A beam element is adopted for modeling the girder and the pylons. Whereas, a two-node catenary cable element derived using exact analytical expressions for the elastic catenary, is adopted for modeli...

The nearly 21-year-old Jiujiang Bridge, which is suffering from uneven line shape, constant great downwarping of the main beam and cracking of the box girder, needs reinforcement and cable adjustment. It has undergone cable adjustment for twice with incomplete data. Therefore, the initial internal force state of the Jiujiang Bridge is identified as the key for the cable adjustment project. Base...

To improve the stability of the magnet-girder assemblies in the ESRF storage ring, vibration investigations have been carried out for in situ magnet-girder assemblies and a prototype. Characterisation tests were performed : operating response measurements, static stiffness measurements, modal testing. A finite element modelling (FEM) is being carried out for the prototype assembly. First result...

This paper presents the design and the experimental result of the active position control of a shape memory alloy (SMA) wire actuated composite beam. The composite beam has a honeycomb structure with SMA wires embedded in one of its face sheets for the active actuation. The potential applications of this experiment include thermo-distortion compensation for precision space structure, stern shap...

The presence of chemical bonding between functionalized carbon nanotubes and matrix in carbon nanotube reinforced composites is modeled by elastic beam elements representing covalent bonding characteristics. Neglecting other reinforcing mechanisms in the composite such as relatively weak interatomic Van der Waals forces, this model shows close results to the Rule of Mixtures model’s prediction ...

The composites provide design flexibility because many of them can be moulded into complex shapes. The carbon fibre-reinforced epoxy composites exhibit excellent fatigue tolerance and high specific strength and stiffness which have led to numerous advanced applications ranging from the military and civil aircraft structures to the consumer products. However, the modelling of the beams undergoin...

In order to evaluate the mechanical condition and working performance of a rigid frame bridge after reconstruction extension, was analyzed by static load test. Static test is stress at each section main beam under action partial medium load. The results show that, load, check coefficient strain deflection measuring point box girder does not exceed standard limit value 1, relative residual or de...