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SUMMARY Conceived as a potential alternative to the classical design methods employed for analyzing the stability of underground structures driven in jointed rocks, the homogenization approach stems from the heuristic idea that, from a macroscopic point of view, a rock mass cut by a network of joints may be perceived as a homogenized continuum. The strength properties of the latter can be theoretically obtained from the failure conditions of its individual constituents: rock matrix and joint interfaces. At the material level, the limit analysis reasoning is used in the context of homogenization to formulate the homogenized strength criterion of a jointed rock mass in the particular situation of a single set of parallel joints. As it could be expected, the obtained closed‐form expressions show the strength anisotropy induced by joint preferential orientation. The support functions (π functions) associated with the homogenized strength criterion are also determined in both plane strain and three‐dimensional cases. This criterion is then applied to the investigation of stability analysis of a tunnel excavated in a jointed rock mass. Upper bounds estimated of the stability factor are derived from the implementation of the kinematic approach directly on the homogenized underground structure. Finally, the approach is applied to analyze and discuss the collapse of the Pinheiros subway station (São Paulo, Brazil). Copyright © 2014 John Wiley & Sons, Ltd.

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Widespread adoption and acceptance of pervious concrete systems in new areas using local materials and equipment are dependent on having information on the efficacy of the mix and their longterm needs for rehabilitation. In Porto Alegre, Brazil recent governmental mandates include incorporating permeable pavements into projects. This study expanded on research into the effectiveness of using readily available aggregate for adequate hydraulic performance and clogging resistance of pervious concrete to also determine the effectiveness of maintenance procedures. Laboratory specimens from three mixes with differently screened aggregate were cast and infiltration rates evaluated initially, post clogging, after sweeping and after powerwashing. The results indicate that all three mixes maintain similar hydraulic functionality after rehabilitation, and that powerwashing is more effective in rejuvenating infiltration capabilities than sweeping. In addition, it is recommended to perform infiltration testing twice after maintenance, as there is a slower rate measured on the second test, probably due to dislodged debris re-entering the system during the first test. Similar laboratory methodologies for mix design and maintenance evaluation might effect a faster and more efficient incorporation of this sustainable low impact development technology in other regions.