Study on residual strength of concrete filled steel tube after exposure to explosing impact
The residual bearing mechanism of concrete filled steel tubular beams with different casing hoop steel coefficients after exposure to explosing impact were experimentally investigated. The experiments were carried out on the reaction frame for loading, and the pressure and the residual deformation modes were recorded. The results show that the concrete filled steel tubular beams have good anti-explosion ability and the casing hoop steel coefficient is an important factor to the value of residual strength.
Hollow and concrete filled steel hollow sections under transverse impact loads
Abstract Steel hollow sections are used extensively in the construction, offshore, mining and security industries. In many applications these sections are concrete filled in order to gain strength advantages under axial compression loads. These sections may be subjected to transverse impact loads from accidental or intentional impacts or explosive events. This paper reports an experimental and analytical investigation of hollow and concrete filled steel square hollow (SHS) section beams subjected to low velocity, large mass transverse impacts at the beam mid-span. Three different section sizes were tested as fully clamped beams, where the impact energy was sufficiently large so as to cause complete failure of the beam by tensile tearing. It is shown that non-compact hollow sections undergo local deformations beneath the impactor, and when concrete filled these sections can sustain greater transverse impact loads as the local deformations are restricted from forming. The effect is shown to be less pronounced for compact sections. An elastic–plastic theoretical method is developed to establish the force–displacement and energy absorption relationships for hollow and concrete filled sections, and is shown to compare well with the experimental results. The local reduction of the section at the point of load application is explicitly included. A design procedure is developed whereby the analyst may use a deflection, force or energy limit to design hollow and concrete filled steel SHS members for transverse impact loads.
INVESTIGATION OF RESISTANCE AND BEHAVIOR OF REINFORCED CONCRETE MEMBERS SUBJECTED TO DYNAMIC LOADING. PART III. Civil Engineering Studies, Structural Research Series No. 243
An investigation was made to obtain, by means of tests, information which will contribute to a better understanding and more accurate prediction of the strength and behavior of reirforced concrete structures subjected to dynamic loading. The immediate objective was the determination of the resistance and behavior of simple-span reirforced concrete beams subjected to impulsive loading. To accomplish this, tests of beams and of reinforcing bar coupons were made and the resulting data analyzed. The practicability of an existing method of computing the resistance of dynamically loaded reinforced concrete beams was also checked. To this end, comparisons were made between the test results and the prediction of the method of analysis. (auth)