Structural safety uncertainties in codes of practice for reinforced concrete

The limit-state design approach, currently used in codified design of concrete structures reinforced with steel reinforcement, is based on semi-probabilistic procedures. Although modern concrete codes of practice are more sophisticated than older codes based on the permissible stress approach, they still have fundamental uncertainties with regards to structural safety. The work reported in this paper investigates these uncertainties for the BS 8110 and Eurocode-2 codes of practice by performing a structural reliability assessment using the Monte-Carlo Simulation method in conjunction with the Latin Hypercube and Conditional Expectation variance reduction techniques. The assessment considers both the flexural and shear failure modes. In the case of BS 8110, it is shown that it may be more appropriate to increase the characteristic value of the tensile strength of steel reinforcement rather than to use the reduced partial safety factor of 1.05. © Kyriacos Neocleous, Kyprous Pilakoutas, Peter Waldron

Thin FRP/GFRC structural elements

This paper presents background work leading to the development of thin structural elements made of GFRC (Glass Fibre Reinforced Concrete) reinforced with FRP (Fiber Reinforced Polymer) bars. Such thin structural elements are suitable for a variety of applications such as cladding, security screens, etc, but this paper focuses on their use as permanent formwork. The first part of the paper deals with optimising a uniform thickness GFRC section to achieve maximum flexural capacity at minimum weight. The second part deals with the interaction between FRP and GFRC, in particular with the issues of bond. The third part presents the performance of a 3 m span thin GFRC permanent formwork panel system reinforced with FRP. Both experimental and analytical studies are presented and it is concluded that FRP/GFRC thin structural elements can be designed using conventional techniques requiring only the use of appropriate material characteristics

Punching shear behavior of fiber reinforced polymers reinforced concrete flat slabs: experimental study

This paper presents the results of a two-phase experimental program investigating the punching shear behavior of fiber reinforced polymer reinforced concrete (FRP RC) flat slabs with and without carbon fiber reinforced polymer (CFRP) shear reinforcement. In the first phase, problems of bond slip and crack localization were identified. Decreasing the flexural bar spacing in the second phase successfully eliminated those problems and resulted in punching shear failure of the slabs. However, CFRP shear reinforcement was found to be inefficient in enhancing significantly the slab capacity due to its brittleness. A model, which accurately predicts the punching shear capacity of FRP RC slabs without shear reinforcement, is proposed and verified. For slabs with FRP shear reinforcement, it is proposed that the concrete shear resistance is reduced, but a strain limit of 0.0045 is recommended as maximum strain for the reinforcement. Comparisons of the slab capacities with ACI 318-95, ACI 440-98, and BS 8110 punching shear code equations, modified to incorporate FRP reinforcement, show either overestimated or conservative results

Recovery of Polyphenols from Brewer’s Spent Grains

peer-reviewedThe recovery of antioxidant polyphenols from light, dark and mix brewer’s spent grain (BSG) using conventional maceration, microwave and ultrasound assisted extraction was investigated. Total polyphenols were measured in the crude (60% acetone), liquor extracts (saponified with 0.75% NaOH) and in their acidified ethyl acetate (EtOAc) partitioned fractions both by spectrophotometry involving Folin–Ciocalteu reagent and liquid-chromatography-tandem mass spectrometry (LC-MS/MS) methods. Irrespective of the extraction methods used, saponification of BSG yielded higher polyphenols than in the crude extracts. The EtOAc fractionations yielded the highest total phenolic content (TPC) ranging from 3.01 ± 0.19 to 4.71 ± 0.28 mg gallic acid equivalent per g of BSG dry weight. The corresponding total polyphenols quantified by LC-MS/MS ranged from 549.9 ± 41.5 to 2741.1 ± 5.2 µg/g of BSG dry weight. Microwave and ultrasound with the parameters and equipment used did not improve the total polyphenol yield when compared to the conventional maceration method. Furthermore, the spectrophotometric quantification of the liquors overestimated the TPC, while the LC-MS/MS quantification gave a closer representation of the total polyphenols in all the extracts. The total polyphenols were in the following order in the EtOAc fractions: BSG light > BSG Mix > BSG dark, and thus suggested BSG light as a sustainable, low cost source of natural antioxidants that may be tapped for applications in food and phytopharmaceutical industries

Superluminal Propagation and Acausality of Nonlinear Massive Gravity

Massive gravity is an old idea: trading geometry for mass. Much effort has been expended on establishing a healthy model, culminating in the current ghost-free version. We summarize here our recent findings -- that it is still untenable -- because it is locally acausal: CTC solutions can be constructed in a small neighborhood of any event.Comment: Contribution to Conference in Honour of the 90th Birthday of Freeman Dyson -- To Appear in Proceeding. v2: Explicit CTC example, and other improvements, adde

Electro/Magneto-Sensitive Elastomers and Lagrangian Electro/Magneto-Statics

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NYS Field Crops Weekly Pest Report- Evaluation 2008

The NYS Field Crop Weekly Pest Report provides timely pest information to field crop extension educators and agricultural professionals. The report compiles weekly pest and crop observations collected by field crop extension personnel across NYS. In addition, the weekly report provides a vehicle to disseminate other relevant IPM information such as pest identification, scouting techniques and a calendar with suggestions for pest management activities. The pest report is distributed to clientele via the Cornell In-house Field Crops List Serve and Cornell Field Crop List Serve.  The audiences that subscribe to these list-servers include: Extension Educators, crop consultants, growers, agribusiness, and Cornell University Faculty. Twenty three issues of the NYS Weekly Pest Report were published in 2008. Extension Educators and crop consultants utilize the Weekly Report as an overview of timely pest information, and have found the report useful in alerting their local clientele regarding pest management issues. About 200 people receive the pest report as an email from our Cornell University based list server. Many of the articles from the report were used in extension newsletters that reached at least 14,000 people

Digital Sociology and Online Music Communities: Models and Lessons from the Internet

With the rise of the internet, work from the of fields of digital sociology, communications/social media studies, and online research methods have become increasingly relevant for music education scholars both investigating and facilitating music teaching and learning in online contexts. While opportunities for online music making, teaching, and learning activities have grown exponentially, the number of online places dedicated to music making, learning, and sharing has exploded with the arrival of COVID as much of the world moves online. What was once an option – going online to teach and learn music – has now become a necessity for most musicians and music educators. What existing models can music educators draw on to teach and learn music in the age of COVID? We explore this question in this, the second of a three-part investigation of online communities of practice. The first study in the series (authors, 2021) surveyed digital music education in formal settings such as schools and institutions. This paper, second in the series, addresses online communities of practice involving music learning in what would usually take place in informal settings. We review current research in informal music education into areas of genre (vernacular, traditional, popular), fan-based, and composition. Our third and future investigation will consider the implications of on and offline convergent music teaching and learning. We contend that the most important and significant aspect of this work is not the technology but rather the sociological perspective -- the interactions and discourse that people have with one another through these digital enablers that render music learning, making, and teaching possible

Cancellation of quantum mechanical higher loop contributions to the gravitational chiral anomaly

We give an explicit demonstration, using the rigorous Feynman rules developed in~\0^{1}, that the regularized trace \tr \gamma_5 e^{-\beta \Dslash^2} for the gravitational chiral anomaly expressed as an appropriate quantum mechanical path integral is $\beta$-independent up to two-loop level. Identities and diagrammatic notations are developed to facilitate rapid evaluation of graphs given by these rules.Comment: 10 pages, LaTeX and psfig (many figures

Independent Expert Scientific Panel – Report on Unconventional Oil and Gas

No abstract available