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The linkages between energy, water and carbon emissions run deep, and call for new ways of thinking about people and their environment. For example, desalination plants guzzle energy, and forests planted to sequester carbon reduce river flows. CSIRO climate expert, Dr Michael Raupach, shares some holistic, integrative approaches to humankind's use of energy, water and carbon., Energy, water and carbon are literally the cradle of life. About three-and-a-half billion years ago, on an Earth very different from the one we now inhabit, carbonbased molecules in a [...]

The application of textile reinforcement can help to increase the load-bearing capacity of masonry building components, especially those subjected to lateral loads caused by wind, earth pressure or earthquake. The reinforcement can be applied externally or be integrated in the bed joint. The key part of an ongoing research project is to investigate the bonding and load-bearing behavior of masonry building components reinforced with textile in thin bed joints with the aim to develop reinforcing elements. With these reinforcing elements for bed joints the construction of basements and higher buildings will be more attractive with masonry. In the first part of the project, the relevant material and bond properties of preselected materials were determined, and a suitable textile was selected. In the second part, four-point bending tests on unreinforced and reinforced masonry wall specimens were carried out in order to investigate the effectiveness of bed joint textile reinforcement to increase the masonry flexural tensile strength. In the third part, a proposal for the design of prototypical reinforcing elements will be worked out. This paper deals with the two first parts of the research project.

Concrete sewage systems can be severely damaged when attacked by biogenic sulfide corrosion. While minor aggressive exposures can be accounted by using a high sulfate resistant cement, higher concentrations of acid (pH 3.5) require the sealing and protection of concrete surfaces. Throughout the decades, polymer concrete (PC) has been used in sewage systems due to its high acid resistance. However, it has been limited to newly constructed pipes and manholes as well as local repair. In cooperation with Massenberg GmbH, the Institute of Building Materials Research of RWTH Aachen University developed a new way of applying PC for the rehabilitation of damaged concrete surfaces of sewage systems; by dry spraying an epoxy mortar on concrete, layers with an average thickness of 20 mm on vertical and overhead surfaces were successfully produced. The dry sprayed PC was examined for its overall performance such as strength, adhesion, thermal expansion, and wear. A special focus has been put on the diffusion properties and the durability in an acidic environment. Based on these positive laboratory results, a first practical application in a waste water structure is currently underway.

Any limit on future global warming is associated with a quota on cumulative global CO2emissions. We translate this global carbon quota to regional and national scales, on a spectrum of sharing principles that extends from continuation of the present distribution of emissions to an equal per-capita distribution of cumulative emissions. A blend of these endpoints emerges as the most viable option. For a carbon quota consistent with a 2 °C warming limit (relative to pre-industrial levels), the necessary long-term mitigation rates are very challenging (typically over 5% per year), both because of strong limits on future emissions from the global carbon quota and also the likely short-term persistence in emissions growth in many regions.

The article offers information on the annual report card of the Global Carbon Project released in 2014 about national and global trends in carbon dioxide (CO2) emissions. It mentions that the report predicts that global emissions from cement production and burning fossil fuels will increase by about 2.5% in 2014 as it reached 36 billion tonnes of CO2 in 2013.

The paper focuses on the relationship between the effective hydrophobic layer thickness and the durability of impregnated hydrophobic treatments using single-sided nuclear magnetic resonance measurements. Weathered and non-weathered specimens were compared to detect the influence of different exposures on the performance of hydrophobic layers. The results show that structural changes caused by carbonation of blast furnace cement based concrete have an effect on the hydrophobic layer thickness while the carbonation of Portland cement concrete has none.

Das Potential der NMR‐MOUSE® als mobiles zerstörungsfreies Messsystem im Bereich der Bauwerkserhaltung wird anhand zweier Beispiele erläutert. Das erste Beispiel behandelt den Feuchtetransport in Feinbetonen während im zweiten die Bestimmung der Schichtdicken ausgewählter Oberflächenschutzsysteme dargestellt wird.

Die Dauerhaftigkeit, d. h. die Reduktion der Zugfestigkeit über die Lebensdauer von textilen Bewehrungsstrukturen in Betonbauteilen ist ein wesentlicher Bestandteil der Bemessung dieser Bauteile, da nur die am Ende der Lebensdauer zur Verfügung stehende Zugfestigkeit bei der Bemessung berücksichtigt werden kann. Die Bewehrungsstrukturen in textilbewehrten Bauteilen bestehen üblicherweise aus sogenanntem alkali‐beständigem Glas (AR‐Glas), dessen Dauerhaftigkeit in Beton allerdings trotz der chemischen Veränderungen der Glaszusammensetzung aus technischer Sicht nicht zufrieden stellend ist. Im Beitrag wird eine Möglichkeit zur Verbesserung der Dauerhaftigkeit mittels polymerer Tränkung der Bewehrung vorgestellt und gezeigt, inwieweit eine Verringerung des langfristigen Festigkeitsverlustes durch den Einsatz unterschiedlicher Epoxidharze erreicht werden kann.

Brücken aus Stahl‐ und Spannbeton werden heute i. d. R. für Nutzungsdauern von 100 Jahren geplant. Insbesondere bei Großbrücken liegen häufig Bedingungen vor, die besondere Lösungen erfordern, wie z. B. bei außerordentlichen korrosiven Beanspruchungen. Beispielhaft wird in diesem Aufsatz die Situation von Pfeilern im Meerwasser näher beleuchtet, die einem ständigen Chloridangriff unterliegen. Soll die Dauerhaftigkeit beispielsweise durch besonders hohe Qualität der Betondeckung erreicht werden, so sind besondere Nachweise zu führen, für die in den letzten Jahren interessante probabilistische Bemessungsansätze entwickelt wurden (s. z. B. [1] bis [3]). Ferner kann die Dauerhaftigkeitsprognose durch Einsatz von Monitoringsystemen kontinuierlich zugeschärft werden, so dass durch Anwendung der Sicherheitsbetrachtungen wirtschaftliche Lösungen ermöglicht werden. In dieser Veröffentlichung wird anhand der Pfeiler der mit 36 km längsten Meeresbrücke der Welt gezeigt, wie die Dauerhaftigkeit unter schwierigen Bedingungen über einen geplanten Nutzungszeitraum von 100 Jahren sichergestellt wird.

Net primary production links the biosphere and the climate system through the global cycling of carbon, water and nutrients. Accurate quantification of net primary productivity (NPP) is therefore critical in understanding the response of the world?s ecosystems to global climate change, and how changes in ecosystems might themselves feed back to the climate system.  Twelve model estimates of long-term annual NPP for the Australian continent were reviewed. These models varied considerably in the approaches adopted and the inputs required. The model estimates ranged 5-fold, from 0.67 to 3.31GtCy?1. Within-continent variation was similarly large, with most of the discrepancies occurring in the arid zone of Australia, which comprises most of the continent. It is also within this zone that empirical NPP data are most lacking. Comparison with a recent global-scale analysis of six dynamic global vegetation models showed a similar level of variability in continental total NPP, 0.38 to 2.85GtCy?1, and similar within-continent spatial variability. As a first tentative step towards model validation the twelve NPP estimates were compared with existing field measurements, although the ability to reach definitive conclusions was limited by insufficient data, and incompatibilities between the field-based observations and the model predictions. It was concluded that the current NPP-modelling capability falls short of the accuracy required for effective application in understanding the terrestrial biospheric implications of global atmospheric/climatic change.  Potential methods that could be used in future work for improving modelled estimates of Australian continental NPP and their validation are discussed. These include increasing the spatial coverage of empirical NPP estimates within arid ecosystems, the use of existing high quality site data for more detailed model exploration, and a formal model inter-comparison using uniform driver datasets to investigate more intensively differences in model behaviour and assumptions.