A new line of blast-resistant steel doors for the minimum anti-terrorism market was developed and validated for the manufacturer through combined experimental and analytical research. Full-scale shock tube blast testing was used to determine the response of the doors relative to ASTM F2927 door and glazing classifications. A number of parameters affecting door response were considered, including door aspect ratio, construction methodology, door-frame construction, as well as anchor size and quantity. The experimental portion of the study was complemented by an analytical investigation to develop door design tools. Finite element analysis was employed to generate door resistance curves. This was followed by single-degree-of-freedom dynamic analyses to predict the various levels of protection for the blast scenarios studied.
Historic sash windows protected by “SecureTM” security blinds were tested under simulated blast loading using a shock tube in order to establish the blast performance of the blinds. The security blinds were placed near the inside face of the windows and consisted of vertical blades and an optional horizontal locking bar. The specimens were tested with different orientations of the blades from fully-closed to fully-open. Reflected pressures on windows ranged between approximately 12 kPa and 70 kPa, with almost constant duration (varying between 13 ms and 16 ms). The shades were effective in reducing the debris generated by blast pressures, however, a failure mode was observed at shade opening greater than 45 degrees whereby wood debris from the frame wedged between the blades and prevented them from closing. No damage or permanent deformation of the shades was observed.
High strain-rate loading on the flexural response of typical light-frame wood construction was investigated. Stud grade spruce-pine-fir (S-P-F) lumber specimens were tested within a range of low and high strain-rates between 6×10-6 1/s to 0.4 1/s using a servohydraulic actuator and a shock tube.
As-built and glass-fiber-reinforced polymer (GFRP)-retrofitted reinforced concrete columns were subjected to simulated blast loading using a shock tube. Retrofitting involved various configurations of longitudinal and transverse GFRP layers to enhance flexural and shear capacity. Retrofitting significantly increased the strength and stiffness of reinforced concrete flexural members and greatly improved blast response. Furthermore, the addition of transverse GFRP wraps led to enhancements in the debonding strain and behavior of longitudinal GFRP, as well as an increase in post-peak ductility of concrete.
Litebuilt’s 1200 kg/m3 “LiteBlok” lightweight aerated concrete “Jumbo” block product is intended for use in non load-bearing wall construction suitable for interior applications, with a minimum equivalency equal to traditional masonry construction. Experimental tests were conducted to establish the structural behaviour of LiteBlok prisms subjected to concentric and eccentric axial compression, as well as to study the flexural behaviour of LiteBlok walls having a plane of failure parallel and perpendicular to the bed joint. Results showed the importance of using reinforcement in LiteBlok construction to improve capacity and limit the development of cracks in the blocks and in the grout. Furthermore, owing to the use of lightweight aerated concrete and an interlocking bed joint mechanism, LiteBlok was found to benefit from rapid dry-stack construction. Compared to the constructability of conventional masonry, these specific attributes are a major competitive advantage.
The Canadian Safety and Security Program (CSSP) funded the University of Ottawa to develop blast-resistant window retention anchors to improve Canada’s preparedness and prevention capabilities against blast threats. The project included a significant experimental component consisting of shock tube blast testing of full size windows anchored to different substrates (concrete, steel block masonry and stone masonry). The objectives of the tests were to collect much-needed experimental data on anchor performance, develop new design tools and procedures, and develop a new national design standard on blast-resistant window retention anchors, CSA S852. The experimental data obtained from blast testing of windows was used to validate analysis procedures developed for the purpose of blast-resistant window anchorage design and assessment.
This study applied advances in big data and visual data analytics to the field of protective design. A database of historical terrorist activities was analyzed using the Tableau visual data analytics software package to identify meaningful trends in historical data and demonstrate sensitivity of assets to particular types of terrorist attacks by non-state actors based on key geographic, socioeconomic, and contextual characteristics. The research will support improvements to existing terrorism risk methodologies leading to cost-effective, risk-informed decisions to identify the most vulnerable buildings in a large portfolio of buildings.
An analytical procedure was developed to generate the load-deformation characteristics of laterally restrained reinforced concrete members, a phenomenon commonly referred to as compression membrane arching action.
The capacity of typical blast door construction and and in-situ hardware performance were characterized through quasi-static flexural testing of beams whose internal construction closely mimics that of a full-size door.