O Fortalecimento da Cidadania como Estratégia de Design para Prevenção de Crimes

In addition to police action, other factors contribute to crime prevention, including design. The Crime Prevention through Environmental Design (CPTED) approach uses design to modify the offender's perception of the opportunity and benefits of crime. The goal of the research was to identify in Parque do Confisco (Belo Horizonte, Minas Gerais, Brazil), based on CPTED, factors that would stimulate criminal practice, as well as to verify if it would be possible to eliminate these factors. To this end, bibliographic research and spatial observation in the field were carried out. The analysis was based on the three strategies of CPTED: natural access control, natural surveillance and territorial reinforcement, as well as the investigation considered some aspects of the 3D approach (Designation, Definition and Design), typical of CPTED. The results revealed that low visibility, depredation and poor maintenance are the main aspects that stimulate criminal practice in the area. It is possible to implement improvements, however, it is necessary to build integrated projects that consider both physical and behavioral dimensions.Além da ação policial, outros fatores contribuem para a prevenção do crime, dentre eles, o design. A abordagem Crime Prevention Through Environmental Design (CPTED) utiliza o design para modificar a percepção do transgressor quanto à oportunidade e o benefício do crime. O objetivo da pesquisa consistiu em identificar no Parque do Confisco (município de Belo Horizonte, estado de Minas Gerais, Brasil), sob a ótica do CPTED, fatores que favoreceriam a prática criminosa, bem como verificar a possibilidade de supressão desses fatores. Para tanto, elaborou-se pesquisa bibliográfica e observação espacial em campo. A análise dos dados teve como base as três estratégias do CPTED: controle natural de acesso, vigilância natural e reforço territorial, bem como considerou alguns aspectos da abordagem 3D (Designação, Definição e Design), típica do CPTED. Os resultados revelaram que a baixa visibilidade, a depredação e a manutenção precária são os principais aspectos que favorecem a prática criminosa no local. É possível implantar melhorias, porém, faz-se necessária a construção de projetos integrados que considerem tanto as dimensões físicas quanto as comportamentais

Mechanical properties and microstructure of high performance concrete containing stabilized nano-silica

Nanotechnology can significantly improve the mechanical strength and durability of concrete. At thenanoscale, good dispersion of constituent materials is an essential factor for the improvement of concreteproperties. In this scenario, the objective of this research was to evaluate the mechanical properties of highperformance concrete containing stabilized nano-silica. The incorporation of nano-silica to thepolycarboxylate chemical admixture allowed its application in concrete, since the nano-silica was evenlydispersed in the concrete mass. For this study, three different concretes were employed: a reference concrete,one containing stabilized nano-silica and another containing a mixture of silica fume and stabilized nanosilica.The evaluated concrete mechanical properties were the axial compressive strength and secant modulusof elasticity measured in three different ages. The results indicated a substantial increase in concretecompressive strength and modulus of elasticity with the addition of stabilized nano-silica combined with areduction in cement content. The results also showed that use of stabilized nano-silica proved to be veryadvantageous, especially when mixed with silica fume. When they were combined, a synergy effect occurredin the concrete that was of chemical nature in addition to the physical effect of better concrete particlepackaging. Analysis by scanning electron microscopy showed the improvement in microstructure ofconcretes with stabilized nano-silica, which contributed to gains in mechanical properties