Gartner E.M.,Lafarge |
MacPhee D.E.,University of Aberdeen
Cement and Concrete Research | Year: 2011
The drive towards sustainability in construction is shaping our attitudes towards alternatives to Portland cement. Although the cement and concrete industry is essentially sustainable with respect to raw materials supply, and concrete manufacture actually gives relatively low CO2 emissions per unit volume compared to most competitive construction materials, the current focus on climate change has led to concerns about cement industry-generated CO2. Thus, there is interest in developing alternative cements with lower associated CO2 emissions. This paper seeks to provide a context for innovative development through a review of what is meant by a hydraulic cementitious binder, identification of key physico-chemical properties of successful binders and how novel systems generally rely on similar factors. Concepts such as reactivity, availability of reactive species and physico-chemical drivers for the formation of cementitious systems are discussed as a basis for introducing and reviewing recent developments in the search for ever more environmentally sustainable cements. © 2011 Elsevier Ltd. All rights reserved.
Agency: Cordis | Branch: H2020 | Program: IA | Phase: EeB-01-2014 | Award Amount: 7.62M | Year: 2015
Concrete is the most widely used man-made material on Earth, with an annual consumption of around 10 billion m. However, its fabrication is characterized by total CO2 emissions amounting to around 5% of the worldwide anthropogenic GHG emissions. More sustainable cements with lower embodied energy and CO2 footprint are needed. As stated in the European Directive on Energy Performance of Buildings (COM 2010/31/EU), the development of better performing insulation materials and lightweight systems for building envelopes is crucial, playing a significant role in the reduction of buildings operational energy while complying with the load bearing features of existing building structures. The ECO-binder project aims to implement industrial R&D activities on the results of previous research, demonstrating the possibility of replacing Ordinary Portland Cement (OPC) and OPC based concrete products with new ones based on the new Belite-Yeelimite-Ferrite (BYF) class of low-CO2 binders to develop a new generation of concrete-based construction materials and prefabricated building envelope components with more than 30% lower embodied energy, 20% improved insulation properties and 15% lower cost than the actual solutions based on Portland cement. The new building envelope solutions will integrate multiple functions in a single product package, providing the higher performances in terms of acoustic insulation/absorption, fire resistance, dimensional stability, indoor air quality optimization, at an affordable cost. Demonstration of full-scale retrofitting and construction will be performed prototyping and installing a family of prefabricated concrete systems of different complexity and end-use in four different climatic conditions involving public authorities.. Results will be validated through dedicated LCAs, fostering the construction materials sector progress towards increased performing and eco-sustainable products.
Agency: Cordis | Branch: H2020 | Program: RIA | Phase: WASTE-3-2014 | Award Amount: 7.67M | Year: 2015
EU28 currently generates 461 million tons per year of ever more complex construction and demolition waste (C&DW) with average recycling rates of around 46%. There is still a significant loss of potential valuable minerals, metals and organic materials all over Europe. The main goal of HISER project is to develop and demonstrate novel cost-effective technological and non-technological holistic solutions for a higher recovery of raw materials from ever more complex C&DW, by considering circular economy approaches throughout the building value chain (from the End-of-Life Buildings to new Buildings). The following solutions are proposed: - Harmonized procedures complemented with an intelligent tool and a supply chain tracking system, for highly-efficient sorting at source in demolition and refurbishment works. - Advanced sorting and recycling technologies for the production and automated quality assessment of high-purity raw materials from complex C&DW. - Development of optimized building products (low embodied energy cements, green concretes, bricks, plasterboards and gypsum plasters, extruded composites) through the partial replacement of virgin raw materials by higher amounts of secondary high-purity raw materials recovered from complex C&DW. These solutions will be demonstrated in demolition projects and 5 case studies across Europe. Moreover, the economic and environmental impact of the HISER solutions will be quantified, from a life cycle perspective (LCA/LCC), and policy and standards recommendations encouraging the implementation of the best solutions will be drafted. HISER will contribute to higher levels of recovered materials from C&DW from 212 Mt in 2014, to 359 Mt in 2020 and 491 Mt by ca. 2030, on the basis of the increase in the recovery of aggregates, from 40% (169 Mt) to more than 80% (394 t) and wood, from 31% (2.4 Mt) to 55% (5 Mt);. Similarly, unlocking valuable raw materials currently not exploited is foreseen, namely some metals and emerging flows.
Cement and Concrete Research | Year: 2011
The new mechanism proposed by Juilland et al.  to explain the induction period in alite hydration is discussed with reference to the free energy of dissolution under typical hydration conditions calculated from published data. It is concluded that the proposed mechanism is theoretically possible but requires an unusually high interfacial energy for step formation, plus an unusually large increase in dissolution rate over small changes in the degree of solution undersaturation, compared to typical published values for silicate minerals. It is suggested that comparisons with the hydration rates of CaO and MgO might shed further light on the mechanism. © 2011 Elsevier Ltd.
Lafarge | Date: 2014-09-17
The present invention discloses a unitized precast grillage foundation for supporting a structure comprising: a plurality of anchoring elements defining a grid for resting on an underlying surface; a base connected on the grid, the base comprising at least a first footing and a second footing spaced apart and at least one connecting member between and connected to the at least first footing and the second footing; and a beam-column projecting upwardly from the base, and a method of making same.