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Higher levels of inflammatory biomarkers are associated with an increased risk of perioperative atrial fibrillation and myocardial injury after non-cardiac surgery (MINS). Colchicine is an anti-inflammatory drug that might reduce the incidence of these complications.

In this paper, the durability of fabric formwork-based concrete made from supersulfated cement was studied. The study involved comparison of chloride and carbonation resistance, pH values, and water absorption between of surfaces of SSC, the one being cast and the other cast in fabric formwork. It was shown that the use of fabric formwork minimized the pore volume near the surface, maintained the pH values at higher profile depths and showed improved durability when compared to the mould-cast surface. Carbonation depths were reduced by approximately 35% and calculated ab sorption rates were found to be approximately 40% lower at the fabric cast surface, indicating that fabric formwork is a promising aspect towards promoting the comeback of SSC in construction.

The objective of this research program was to study carbon fiber reinforced polymer (CFRP) strengthening of reinforced concrete (RC) members which have concavely-curved soffits. In the presence of such curvature, the FRP laminates attempt to straighten under tension, leading to direct transverse tensile stress at the adhesive-concrete interface, which may cause premature peeling. This tensile stress could also lead to concrete cover delamination. Ten beams, each 6 m in length and having the same soffit curvature (i.e., 4 × 10-5mm-1or in-1), extending over 1, 3 and 5 meters, were tested under three-point static flexure. Two different types of CFRP strengthening techniques, namely wet layup laminates and pultruded precured laminates, were used for external strengthening. One of the beams strengthened with CFRP wet layup laminates (with a curved soffit over an extent of 5 m), used glass FRP spike anchors to prevent peeling. Beams with soffit curvature limited to an extent of 1 m, failed at similar loads when compared with control specimens containing flat soffits. For beams having a soffit curvature extending over 3 and 5 m, reduction in strength was observed because of premature peeling. Inclusion of the GFRP spike anchors with the wet layup system led to a performance superior to the control specimen (flat soffit) confirming that application of GFRP spike anchors delays premature peeling.

The predicted shear capacity of existing reinforced concrete bridge beams is an important subject that needs to be addressed in more detail. Concern has been expressed about whether the current bridge assessment code for the United Kingdom is too conservative when evaluating the shear resistance of existing concrete beams that contain considerable amounts of top (compression) steel, ignored during assessment. This paper looks at the beneficial effects of such compression steel on the shear strength of reinforced concrete beams. The results of laboratory testing are compared with the current code predictions for the shear strength of beams assumed to contain solely tension steel. Further comparisons are made with an upper-bound plasticity solution which is able to consider all steel reinforcement in a concrete beam. There are several reasons why bridges exhibit hidden reserves of strength, with compressive membrane action probably the most important. However, reasons such as the presence of compressive steel will contribute to hidden strength, so that research of this kind is required to enable realistic assessments and strength predictions to be carried out. It is shown that the presence of top (compression) steel has a significant effect on the shear capacity of reinforced concrete bridge beams which contain shear stirrup reinforcement.

This Paper is the second of three on the behaviour of anchorage zones for prestressed concrete. Details are presented of a plasticity approach to the ultimate strength analysis of concrete prisms strip-loaded through rigid steel plates. Such a loading arrangement is assumed to represent adequately the transfer of force from tendon to concrete at the anchorage of a prestressed concrete structure. The effects of steel reinforcement are included in the analysis, which is assumed to satisfy plane strain conditions. lke Mod$ed Mohr-Coulomb failure criterion with non-zero tension cut-off is used for the concrete. A model, based on experimental evidence, is used as the basis for the plastic analysis, and good correlation is obtained between the theory developed here and the observed test results. It is concluded that such a plasticity approach is useful in assessing the strength of concrete under concentrated load.

This Paper is the first of three on the behaviour of anchorage zones for prestressed concrete. Details of an experimental investigation carried out to determine the behaviour of concrete prisms strip-loaded through rigid steel plates are presented. This loading arrangement represents the transfer of force from tendon to concrete at the anchorage of a prestressed concrete structure. The results of several tests have shown that present design methods of anchorage zones are generally very conservative, which leads to an excessive quantity of steel reinforcement in this highly stressed region, that can lead to poor-quality compaction. It has been found, however, that the spreading of such steel over depths greater than those presently used could perhaps relieve this congestion with little loss in strength of the anchorage. Out-of-plane failures during strip-loading tests were also encountered. Proof must therefore be obtained that such third-direction failure cannot occur in practice if planar failure of the anchorage has been assumed during analysis.

This Paper is the last of three on the behaviour of anchorage zones for prestressed concrete. Details of a lower-bound approach to the ultimate load analysis of concrete prisms strip-loaded through rigid steel plates are presented. The previous papers of the series presented experimental results and analytical plasticity solutions to this problem. This Paper extends the plasticity solution by using a finite element approach, thus enabling three-dimensional failure mechanisms encountered during the experiments to be studied successfully. The analysis is conducted in two stages: the first to determine the cracked state of the anchor block; the second to determine the final failure load. It is shown that such an approach is useful in the design of anchorage zones for prestressed concrete.

This paper describes the calibration of a two-dimensional (2D) plasticity-based upper-bound analysis model for the assessment of shear in reinforced concrete beams. This work is part of an ongoing research effort at the University of Cambridge, aimed specifically at the assessment of shear in existing concrete bridges. Due to ductility limitations in concrete, full strength may not be achieved along the assumed lines of discontinuity during collapse, as assumed in a plasticity analysis. For this reason, an ‘effective strength’ of concrete is introduced, which is simply a fraction of the compressive cube strength of the concrete. In order to develop a suitable overall (3D) collapse analysis technique for concrete beam-and-slab bridges, it is necessary to determine this effective strength of concrete in each of the beam and slab portions. Here, a 2D beam shear collapse model, and an associated expression for the effectiveness factor for the concrete, are formulated and calibrated against several test results. Restrictions on the use of this model are established and it is concluded that such an analysis technique is eminently suitable for extension to the more general 3D collapse problem in existing concrete beam-and-slab bridges.

Shear assessment of concrete beam-and-slab bridges T. J. Ibell, BSc(Eng), PhD, C. T. Morley, MA, PhD, CEng, MICE, and C. R. Middleton, BE(Hons), MSc, DIC, PhD, CEng, MICE, MIE(Aust) A three-dimensional upper-bound plasticity solution to the problem of shear assessment of existing concrete bridges is presented. A review of present shear assessment methods for concrete bridges is provided, and shortcomings highlighted. A series of tests on concrete beam-and-slab bridges is described...

Several letters to the editor in response to articles in previous issues of the periodical "New Zealand Listener" are presented including "King of Fantasy," "The Children's Crusade," and "The Colony Strikes Back."