Haruji Tsubota

Analytical studies on local damage to reinforced concrete structures under impact loading by discrete element method

Abstract This paper proposes a new analytical approach for assessing local damage to reinforced concrete structures subjected to impact load, by applying the discrete element method (DEM). It first outlines the basis concept and analytical formulation of the DEM. Next, it discusses the results of simulation analyses of concrete material tests, uni-axial compression tests and tensile splitting tests conducted to determine appropriate analytical parameters such as material constants, failure criteria and strength increase factors depending on strain rate. Finally, the adaptability of the DEM to local damage to reinforced concrete structures impacted by rigid and deformable missiles is verified through simulation analyses of various types of impact tests. Furthermore, the various impact response characteristics and failure mechanisms, such as impact forces, penetration behavior, reduction in missile velocity and energy transfer process, which are difficult to obtain experimentally, are analytically evaluated by the DEM.

Loading Capacities and Failure Modes of Various Reinforced Concrete Slabs Subjected to High Speed Loading

Abstract The objective of this study was to clarify experimentally and analytically the loading capacities, deformations and failure modes of various types of reinforced-concrete structure subjected to loads applied at various rates. Flat slabs, slabs with beams and cylindrical walls were tested under static, low speed and high speed loading. Analysis was applied to estimate the test results by the finite element method using a layered shell element. The analysis closely simulated the experimental results until punching shear failure occured.

Suspended Roof for the Olympic Skating Arena, Nagano

The 18th Winter Olympics were held in February 1998 in Nagano, Japan, where the Olympic Memorial Arena was the venue for the speed skating competition. The arena, covering an area of 80 × 216 m, co...

The Izumo Dome, Largest Timber Structure in Japan

An all-weather, multi-purpose facility, the Izumo Dome, was recently constructed in Japan. This structure covers a free space 143 m in diameter and reaches a height of 49 m. A note-worthy aspect of...

Nonlinear Analysis of Tension Fabric Structure

Membrane structures possess significant advantages over other conventional structures for enclosing a large volume. Generally speaking, membrane structures are classified into two types, i.e. air-supported type and tensile type.