Axial compression tests on CFRP strengthened CFS plain angle short columns.

A comprehensive test program was performed to experimentally investigate the effect of CFRP strengthening on the axial strength and stability of CFS plain angle short columns subjected to monotonic axial compression. A total of 28 specimens were tested by varying the CFRP strengthening configurations for different column heights. Both uni-directional (CF_UD) and bi-directional (CF_BD) CFRP were considered. The influence of various parameters such as the type of CFRP, fiber orientation, and number of CFRP layers was investigated and discussed in detail. For single layer (ply) of CFRP, CF_UD-0° strengthening configuration resulted in maximum increase of axial capacity by 58.33% and 45.72% (in comparison to bare steel specimens), corresponding to 0.5 m and 1.0 m column lengths respectively. All the bare steel and skin-strengthened specimens failed predominantly due to torsional-flexural buckling mode. Additional layer of CFRP wrapping was found to enhance the axial capacity further and CF_UD-0°/BD was found to possess greater capacity in the case of double layer of CFRP. Adopting cardboard in-fill in addition to CF_UD-0° wrap has prevented the torsional mode of buckling and resulted in a peak increase of axial capacity by 192.55% and 240.61% corresponding to 500 mm and 100 mm long specimens, respectively.

Endoscopic Transnasal Repair of Cerebrospinal Fluid Leakage: Experience in BSMMU.

Endoscopic transnasal repair of CSF rhinorrhoea is gaining popularity around the world because of its tremendous success rate but it depends on defect site, size, technique of repair, experiences of surgeon and also patient's profile. Aim of this study was to analysis of surgical outcome of endoscopic transnasal repair of CSF rhinorrhoea. A retrospective study carried out in the department of ENT and Head neck surgery at Bangabandhu Sheikh Mujib Medical University (BSMMU) from January 2018 to December 2019. Of the total of 24 patients 16(66.0%) were female and 8(33.0%) males. The commonest site of the leak was in the cribriform plate in 18(75.3%) followed by 5(20.8%) in the fovea ethmoidalis, and 1(4.0%) in the sphenoid sinus, the overall success rate of this series with first surgical procedure was 95.83% and 100.0% with a second procedure. Meticulous pre-operative evaluation, proper identification of leakage site, choice of graft materials and surgical technique are keys to attaining excellent results.