Further investigation on the dynamic compressive strength enhancement of concrete-like materials based on split Hopkinson pressure bar tests Part II Numerical Simulations. International Journal of Impact Engineering, Elsevier, 2009, 36 (12) This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. shows that it is necessary to use a kinetic friction model, rather than a constant friction model, for more accurate numerical simulation of SHPB tests. M A N U S C R I P T A C C E P T E D ARTICLE IN PRESS

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Amyloidosis is a spectrum of diseases characterized by abnormal extracellular accumulation of proteinaceous material; its precise etiology still remains unclear. It may affect multiple organs, of which the commonest sites are larynx, bronchus and kidney. Laryngeal amyloidosis is usually a localized phenomenon rarely associated with systemic involvement, here we report a case of laryngeal amyloidosis with tracheobronchial involved. The patient was 31-years old. He had a history of open surgical operation for laryngeal amyloidosis in the left ventricle 4-years ago. This time he was suffered by amyloid deposition in his right ventricle, the lesion was excised on staged laryngoscopy under general anesthesia. After 20-months follow-up, the post-operative recovery was wonderful. The bronchoscopy examination and computerized tomography scan for chest demonstrated he also had right main bronchus amyloidosis. Being of no dyspnea, he was unwilling to accept an operation on bronchus. Though amyloidosis is a benign lesion, up to date, there are no curable treatments for such a disease, for severe cases, it may be fatal as a result of airway obstruction or respiratory failure. Here we review the pertinent references on this subject, and discuss the main managements for amyloidosis on larynx and bronchus.

A AB BS ST TR RA AC CT T Split Hopkinson pressure bar (SHPB) technique has been frequently used to measure the uniaxial compressive stress-strain relation of brittle materials at intermediate strain-rates where pulse-shaping technique is employed to improve the stress uniformity and maintain a nearly constant strain-rate in the specimen during the effective loading period. This paper appraises the functions of the pulse-shaping technique in SHPB tests of brittle samples based on numerical simulations of SHPB tests. It is shown that a proper pulse-shaper can attenuate high frequency oscillations of the incident pulse and increase the rise-time of the pulse, resulting in the improvement of stress equilibrium and uniformity along the axial direction of an SHPBspecimen. However, it is found that the inertia-induced confinement in the radial direction of a brittle specimen is still significant even though the shaped incident stress pulse can generate a nearly flat plateau in the reflected pulse in the SHPB test. It implies that the achievement of a nearly constant strain-rate represented by a nearly flat plateau in the reflected pulse in an SHPB test may not give a true nearly constant strain-rate in the SHPB specimen. It is concluded that the application of the pulse-shaping technique in SHPB tests on brittle materials may not change the nature of the observed transition strain-rate, which represents the transition of the stress state from a uniaxialcompressive-stress-dominated state to a confined compressive stress state, rather than the start of significant strain-rate effect. Therefore, inertia-induced radial confinement effect needs to be considered in the interpretation of any SHPB results for brittle materials even though a pulse-shaper is used.K Ke ey yw wo or rd ds s: : brittle material, split Hopkinson pressure bar, pulse-shaping, strain-rate effect

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