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Elsevier's AAM Policy: Authors retain the right to use the accepted author manuscript for personal use, internal institutional use and for permitted scholarly posting provided that these are not for purposes of commercial use or systematic distribution.Elsevier believes that individual authors should be able to distribute their AAMs for their personal voluntary needs and interests, e.g. posting to their websites or their institution's repository, e-mailing to colleagues. However, our policies differ regarding the systematic aggregation or distribution of AAMs to ensure the sustainability of the journals to which AAMs are submitted. Therefore, deposit in, or posting to, subjectoriented or centralized repositories (such as PubMed Central), or institutional repositories with systematic posting mandates is permitted only under specific agreements between Elsevier and the repository, agency or institution, and only consistent with ABSTRACTThis paper presents an experimental investigation on the effect of concrete compressive strength and confinement method on confined high and ultra high-strength concrete (HSC and UHSC) specimens. A total of 55 fiber reinforced polymer (FRP) confined concrete specimens were tested under monotonic axial compression. All specimens were cylinders with 152 mm diameter and 305 mm height and confined by carbon FRP (CFRP). Three different concrete mixes were examined, with average compressive strengths of 35, 65 and 100 MPa. The effect of the confinement method was also examined with FRP-wrapped specimens compared to FRP tube-encased specimens. Axial and lateral behavior was recorded to observe the axial stress-strain relationship and lateral strain behavior for concentric compression. Ultimate axial and lateral conditions are tabulated and the complete stressstrain curves have been provided. The experimental results presented in this paper provide a performance comparison between FRP-confined conventional normal-strength concrete (NSC) and the lesser understood area of FRP-confined HSC and UHSC. The results of this experimental study clearly indicate that above a certain confinement threshold, FRP-confined HSC and UHSC exhibits highly ductile behavior, however for the same normalized confinement pressures, axial performance of FRPconfined concrete reduces as concrete strength increases. The results also indicate that ultimate conditions of FRP-wrapped specimens are similar to those confined by FRP tubes, however a 2 performance difference is evident at the transition region. The performance of 10 existing stress-strain models were assessed against the experimental datasets and the performance of these models discussed.The results of this model assessment revealed the need for further development for stress-strain models developed specifically for FRP-confined HSC or UHSC.

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The fatigue behaviour of laser engineered net shaping (LENS) deposited Ti-6Al-4V is studied in the as built condition. The fatigue properties are measured, and the influence of microstructure and physical defects on fatigue performance is analysed through microscopy and fractography. Fine basketweave microstructure is obtained using a substrate with large equiaxed grains. The presence and location of unmelted particles are observed to significantly affect fatigue life. On the other hand, smaller gas porosity is not found to have major effect on the fatigue life. Further, the fatigue properties in a 'repair' condition are evaluated through samples consisting of LENS deposited parts joined to a preexisting wrought part. The properties are compared with the as built LENS parts.