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The management of construction and demolition waste (CDW) is essential in the formation, growth and renovation of urban areas. This paper presents part of a study on CDW generation and management in the Lisbon Metropolitan Area (LMA). CDW generation was estimated for 2006 and 2007 based on construction activity and waste load movements. The results revealed that in the municipality of Lisbon, remodeling construction activity prevailed, with CDW generation indicators of 954 t/day and a per capita rate of 0.60 t/year. Both values are above the average for the LMA and its two sub-regions (Greater Lisbon and the Setúbal Peninsula). The installed infrastructure for CDW management identified in the LMA is situated within a maximum distance of about 23 km from the geometric center of the city of Lisbon. Despite the fact these locations favor the municipality of Lisbon, the occurrence of illegal dumps is still a reality. A notable effort towards environmental education addressing CDW management is under way so as to make involved citizens aware of the recent CDW legislation, Decree-Law Nr. 46/2008, as well as of the problems arising from scenarios of environmental degradation and uncontrolled use of natural resources in the civil construction sector. Policies are outlined aiming to move towards the more judicious management of CDW.

Typical high-performance concrete (HPC) mixtures are characterized by low water-cementitious material ratios, high cement contents, and the incorporation of admixtures. In spite of its superior properties in the hardened state, HPC suffers from many practical difficulties such as its sensitivity to early-age cracking (which is associated with self-desiccation and autogenous shrinkage). In this context, conventional curing procedures are not sufficiently effective to address these limitations. In order to overcome this issue, two strategies, which are based on the use of internal reservoirs of water, have been recently developed. One of these strategies is based on the use of lightweight aggregates (LWA), while the other is based on the use of superabsorbent polymers (SAP). This paper studies and compares the efficiency of the LWA and SAP approaches. Moreover, some of the theoretical aspects that should be taken into account to optimize their application for internal curing of HPC are also discussed. Two fine LWA's and one SAP are studied in terms of autogenous deformation and compressive strength. Increasing the amounts of LWA or SAP can lead to a reduction of the autogenous deformation and compressive strength (especially when adding large amounts). By selecting appropriate materials and controlling their amount, size, and porosity, highly efficient internal water curing can be ensured.

This recommendation is written to improve the assessment of the in situ. Compressive strength of concrete in existing structures by combining core strength values and non-destructive measurements. Both average strength and its scatter are considered. Deriving a characteristic strength from the assessment results is not considered here. The recommendation applies for most common techniques (ultrasonic pulse velocity, rebound hammer, pull-out) but also for less common techniques (penetration test, etc.). The recommendation does not apply to situations in which no core has been taken from the existing structure and is limited to situations where NDT is combined with cores. The recommendation introduces the concept of Estimation Quality Level, corresponding to the target of assessment, and which is put in relation with the means and strategy developed for assessing concrete. The text details all steps that must be followed from the data gathering to the checking of the quality of the final estimations. For more clarity, an

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