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Slurry walls have been widely used for retrofitting earthen dams and levees. Slurry wall properties, such as strengths and permeability are well known, but there is very little research on their seismic performance. This research includes shake table testing of two common types of slurry walls: sand-cement-bentonite (SCB), and cement-bentonite (CB) walls. Reduced-scale slurry walls with dimensions of 150 cm (long) x 160 cm (tall) x 20 cm (thick) were constructed inside a rigid, steel box that was mounted on top of a shake table. Boundary conditions in the shake table tests were addressed; and dynamic scaling laws were followed to scale the seismic motions. Specimens were tested under two seismic excitations: modified Loma Prieta earthquake motions and sinusoidal sweep frequency motions from 0.20 Hz to 6 Hz. Accelerations, horizontal deflections, dynamic vertical deformations, and dynamic soil pressures were recorded using accelerometers, linear potentiometers, linear variable differential transducers, and stress cells, respectively. The walls were inspected for damages after testing. Unconfined compression tests were performed on slurry wall specimens to further evaluate the effects of seismic stresses on the strengths of slurry walls. The test results revealed the seismic responses and failure mechanisms of slurry walls under seismic events.

Aedes albopictus (Skuse, 1894), vector responsable de la transmisión del dengue y otros virus es por primera vez reportado en las localidades de Voladero del estado Monagas al oriente del país y en las localidades 5 de Julio y Banco Obrero en el estado Guárico. Se realizaron colectas de adultos posándose sobre humanos y fases inmaduras en un recipiente plástico y en plantas de la familia Araceae con abundante materia orgánica, en el solar de una vivienda. Este reporte nos alerta para extremar la vigilancia entomológica a nivel nacional, determinar la distribución del vector en el país y diseñar estrategias de control. Aedes albopictus (Skuse, 1894), vector responsible for the transmission of dengue and other viruses, is first recorded in the locality of Voladero, Monagas state, east of the country and in the towns July 5 and Banco Obrero, in the state Guárico. Collections were performed for adult human landing and for immature stages in a plastic container and in plants of the family Araceae with abundant organic matter, on the back yard of a house. This report alerts us to exercise extreme national entomological surveillance to determine the vector distribution in the country and control strategies.