NO.7 • DECEMBER 2008 - The Hong Kong Polytechnic University

Recent Events
活 動 剪 影
FACULTY OF CONSTRUCTION AND LAND USE SEMINARS
建 設 及 地 政 學 院 研 討 會
Dynamic Response of Fibre Metal Laminates
Subjected to Impact
Dr. Zhongwei Guan, Senior Lecturer in Structural Engineering at the University
of Liverpool, UK discusses the Dynamic Response of Fibre Metal Laminate
(FMLs) Subjected to Impact. FMLs, thin layers of metal sheets and
unindirectional fibre layers embedded in an advhesive system were patented
over two decades ago, and have superior material properties to resist impact
loading and fatigue. Currently they are being used in the manufacturing of
the American C-17 transport aircraftscargo doors whilst Glass-Reinforced
(GLARE) FMLs are being used in the manufacturing of the upper fuselage of
the A380.
Using FMLs as skins, novel sandwich structures can be made with metallic
foam core or SLM lattice core. They developed numerical models using
explicit algorithms to simulate deformation and failure modes of FMLs
subjected to projectile impact and blast loading. All models are validated
against experimental results, which are used to optimize FMLs. Such work
had huge potential in developing impact/blast resistant structures, especially
in the aerospace industry.
(FMLs)
Zhongwei Guan (FMLs)FMLs
C-17
/GLARE
A380
Consideration of Vertical Acceleration Effects in Seismic
Design of Concrete Highway Bridges
Sashi K. Kunnath, Professor of Structural Engineering at the University of
California at Davis conducted this seminar based on a comprehensive
series of simulations carried out on a range of typical bridge configurations
to isolate the effects of vertical motions on the seismic response of ordinary
reinforced concrete highway bridges. Results reveal that vertical ground
motions can have a significant effect on (i) the axial force demand in
columns; (II) moment demands at the face of the bent cap, and (iii) moment
demands at the middle of the span.
The first two issues are less of a concern in the present study since the axial
capacity of the columns and the moment capacity of the girders at the face
of the bent cap are generally adequate to resist the increase in the respective
demands due to vertical effects. On the other hand, the amplification of
negative moments in the mid-span section is identified as the primary issue
that should be addressed in the context of existing seismic guidelines in
California. In particular, for the current requirement, the vertical effects are
considered as the equivalent to 25% of the dead load applied in the upward
and downward directions. The reinforcement resulting from this requirement
is found to be inadequate for a significant number of cases examined in this
study.
Sashi K. Kunnath
(i) (ii)(iii)
25%
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