This CD-ROM contains 15 papers that were presented at sessions sponsored by ACI Committees 447 and 370 at the ACI Fall 2010 Convention in Pittsburgh, PA. In this publication, engineers report on how they are approaching the challenging task of predicting the response of structures subjected to blast and impact loading. Both experimental and analytical efforts are represented, often in tandem. The analytical approaches taken include single-degree-of-freedom modeling, highly nonlinear transient dynamic finite element simulations, and coupled Lagrangian-Eulerian simulations. Papers in the publication cover the design and evaluation of new and existing structures, as well as techniques for strengthening existing structures. Note: The individual papers are also available. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP-281

Since its initial publication in 1969, Unified Facilities Criteria (UFC) 3-340-02 (formerly Army Technical Manual 5-1300/Navy Publication NAVFAC-P397/Air Force Manual AFR 88-22) has provided uniquely practical and intuitively straightforward procedures for analyzing and designing blast resistant structures. With its unlimited distribution, UFC 340-02 is the blast design manual of choice of both government explosives safety experts and private A-E firms throughout the world. This paper summarizes updates to the blast design guidance in chapter 4, reinforced concrete design. Detailed data are presented on the revisions in three areas: dynamic increase factor, design of diagonal tension reinforcement in walls and slabs, and prediction of concrete spall and breach. The paper concludes with a brief discussion of future work.

This paper presents a rational method to design barrier systems subjected to vehicular impact loading. The method is based on the energy principle using vehicle characteristics. It covers barrier systems with stiffness ranging from rigid to both linear elastic and nonlinear systems subjected to various vehicular speeds. A comparison of the analytical method with test data shows reasonable correlation.

The lack of a complete understanding of shear behavior under high dynamic conditions hindered the efforts for accurate prediction of impact behavior, since severe shear mechanisms may dominate the behavior of RC structures when subjected to impact loads. This current study involves a well-instrumented experimental program that was undertaken to contribute to our understanding of the effects of shear mechanisms on the behavior of reinforced concrete (RC) structures under impact loads. The test results showed that the shear characteristics of the RC beam specimens played an important role in their overall behavior. All specimens, regardless of their shear capacity, developed severe diagonal shear cracks, forming a shear-plug under the impact point. Furthermore, the application of the Disturbed Stress Field Model (DSFM) as an advanced method of modeling shear behavior under impact conditions is also investigated. A two-dimensional nonlinear finite element reinforced concrete analysis program (VecTor2), developed previously for static loads, was modified to include the consideration of dynamic loads such as impacts. VecTor2 analyses of the test specimens were satisfactory in predicting damage levels, and maximum and residual displacements. The methodology employed by VecTor2, based on the DSFM, proved to be successful in predicting the shear-dominant behavior of the specimens under impact.

Carbon fiber anchors can serve to improve the performance of externally applied CFRP (Carbon Fiber Reinforced Polymer) strengthened concrete structures because they do not rely on the bond of the CFRP to the concrete to transfer stresses. This paper seeks to identify the residual strength of externally applied CFRP after damage has been delivered by an instrumented drop-weight impact testing device. The paper further investigates effectiveness of carbon fiber anchors (anchors inserted into predrilled holes and fanned out over the CFRP sheet) in impact damaged specimens. The paper reports the results from 14 impact damaged CFRP strengthened 1.42 m (56 in.) long beams with and without anchors. The research found that impacts from the testing device with a drop height greater than 1.83 m (6 ft) significantly reduced the tensile strength of the CFRP. However, with the use of anchors the same strength can be reached in a damaged CFRP specimen as in an undamaged unanchored specimen. The paper also reports on the effectiveness of the anchors when used to strengthen a reinforced concrete slabs subjected to blast loads and a reinforced concrete beam under impact loading and finds that the anchors are able to fully develop the tensile strength of the CFRP under dynamic loading.