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Fiber-reinforced polymer (FRP) pultruded profiles are produced by a number of manufacturers worldwide in similar, but nonstandard, wide-flange, I, angle, and tubular profiles. At present there is no American National Standards Institute approved design code in the United States for structural design with pultruded FRP profiles. Manufacturers of pultruded profiles each provide their own design equations, design methods, material properties, and safety factors for their pultruded products. There is a need for standardization of production and design of pultruded profiles to enable mainstream use of these profiles in structural engineering practice. The purpose of this paper is twofold: (1) to provide appropriate resistance factors (0 factors) for wide-flange pultruded columns that are compatible with ASCE 7 load factors and (2) to provide a unified analytical equation for local and global buckling of concentrically loaded axial members, which may be appropriate for a future design code. The resistance factors are provided for different target levels of structural reliability, [beta], and for different nominal design properties of the pultruded materials. The resistance factors were determined using Monte Carlo simulation based on the results of 75 tests of full-scale pultruded columns that have been reported in the literature. In addition, resistance factors and structural reliabilities were calculated for the design equations provided by the manufactures in their design codes. The paper demonstrates that a unified design equation for pultruded columns can be developed for LRFD with reliability indices that are similar to those used for conventional materials. The paper also shows that markedly different reliability indices are obtained for the different manufacturer-provided equations even though identical allowable stress design safety factors are recommended by all manufacturers. DOI: 10.1061/(ASCE)ST.1943-541X.0000126 CE Database subject headings: Columns; Structural reliability; Buckling; Flanges; Pultrusion; Load and resistance factor design. Author keywords: Columns; Resistance factors; Reliability; Local buckling; Global buckling; Wide flange profiles; Pultrusion.

Construction continues to be a significant part of the global economy and shapes the built environment and quality of life for people around the world. In the United States, construction is a multibillion dollar annual enterprise, employing nearly l0 million people. However, it appears that the fragmented nature of the industry continues to hamper productivity and hoped-for gains in efficiency. Issues involve an array of regulatory and legal constructs that: (1) redistribute risk; (2) present only low barriers to entry (making company startup somewhat easy); and (3) fail to provide the quality and quantity of labor necessary. These factors continue to produce overall inefficiencies throughout the construction industry, and ill prepare the industry for the formidable challenges of globalization, sustainability, population growth, and wise use of resources. The purpose of this paper is to review the past and present of construction engineering within the context of civil engineering, and to prescribe practical change to revitalize construction engineering education to meet future demands. CE Database subject headings: Construction management; Engineering education; Curricula; Information technology (IT).

As buildings have become larger and house more people, political and societal issues have become more complex, and risks associated with occupying buildings have changed. In particular, since the terrorist attacks of 2001, the anxiety levels and perceived risks of building occupants (especially occupants of tall, high-profile buildings) have increased. These perceived risks include risks of terrorist attacks, natural disasters, the possibility of bomb threats, and catastrophic fires. The public's perception of risk is already incorporated into building design codes and performance-based design (PBD) methods for such hazards as earthquakes and fires--explicitly in some cases, implicitly in others. Risk perception will clearly need to be addressed in the design of buildings, as trade-offs in 'acceptable' risk versus cost must be made. As terrorism represents a constantly changing design challenge, and is a target-specific hazard, as opposed to a location-specific hazard, it seems unlikely that prescriptive code requirements will be entirely effective at addressing this hazard. PBD codes are a promising approach for design issues that deal with such 'cutting-edge' concepts. DOI: 10.1061/(ASCE)0887-3828(2007)21:1(61) CE Database subject headings: Building codes; Risk management; Hazards; Earthquakes; Fires; Terrorism.

The Editorial Board of the American Society of Civil Engineers Journal of Composites for Construction (Lawrence C. Bank, Editor) sponsored a survey of the civil/structural engineering programs around the world on the subject of fiber reinforced polymer (FRP) composites, excluding the traditional steel-concrete composite construction and fiber reinforced concrete. This paper summarizes the main results from the survey. During the last decade, considerable focus has been devoted to the use of FRP composites in construction. The main driving force is the need for revitalizing the aging infrastructure with innovative materials and structural systems that last longer and require less maintenance. As the construction industry embraces FRPs in the field, the need for educating civil engineers with background on the subject has become more evident. Despite a significant number of field applications and laboratory research, the survey shows that FRPs have not yet been fully implemented in the engineering curricula, and the classrooms are still lagging behind. To improve this situation, civil engineering and their extension programs must provide sufficient training on unique features of FRPs so that engineers could design or specify them in construction. This survey should be repeated as a gauging tool again at the end of this decade. CE Database subject headings: Engineering education; Fiber reinforced polymers; Construction; Surveys.

The response of a G4(1S) strong post steel w-beam guardrail system to pendulum impacts has been investigated in a series of full-size physical tests and in simulated experiments using the explicit finite-element analysis code DYNA3D. The physical tests were conducted at the Federal Outdoor Impact Laboratory at the Turner Fairbank Highway Research Center of the Federal Highway Administration in McLean, Va. In the pendulum tests, an 880-kg mass was used to strike the rail perpendicular to its face. The rail section was attached to steel posts and blockouts and supported in a specially designed fixture. Initial velocities of the pendulum at impact were 9.25, 20, 30, and 35 km/h. Acceleration, force, velocity, and displacement histories of the impact event were obtained from accelerometer data taken during the testing. Data from the DYNA3D simulations of the impact tests compared well with the data obtained from the full-scale testing. Displacement plots of the deformed shapes of the rails at 25-ms intervals compared favorably with high-speed film images. Force versus displacement histories showed good agreement with those obtained from quasi-static experiments. The use of pendulum impact tests for screening and evaluation of alternative guardrail systems is recommended.

Results of an experimental and analytical investigation of the behavior of a pultruded fiber-reinforced plastic (FRF) portal frame subjected to short-term static loads are presented. A 6 ft high by 9 ft wide (1.83 m x 2.74 m) plane portal frame was designed and constructed of glass/vinylester pultruded FRP thin-walled sections. Data obtained from short-term load tests on the frame are presented. Failure of the beam-to-column connections and compression flange buckling of the girder are discussed. An analytical investigation was performed to predict the nonlinear response of the frame. The numerical model includes the effects of axial, shear, and flexural deformation of the pultruded numbers, flexibility of the beam-to-column connections, and the postbuckling of the frame girder. An expression for the nonlinear rotational stiffness of the pultruded beam-to-column connection is presented. The experimental data, obtained from the full-size test, are compared with the analytical model., The experimental and theoretical analysis of the short-term response of a full-size pultruded fiber-reinforced plastic portal frame are presented. The linear and nonlinear behavior of the frame including the failure mechanisms are described. Results show that the flexibility of the beam-to-column frame connection determines the frame response. Comparison between experimental and theoretical results also showed good agreement.