José María Fuentes

Use of the labour-intensive method in the repair of a rural road serving an indigenous community in Jocotán (Guatemala).

This paper reports the results obtained in an aid project designed to improve transport in the municipal area of Jocotán (Guatemala). The rural road network of an area occupied by indigenous people was analysed and a road chosen for repair using the labour-intensive method–something never done before in this area. The manpower required for the project was provided by the population that would benefit from the project; the involvement of outside contractors and businesses was avoided. All payment for labour went into the pockets of the local people. The small earth movements made and the use of local materials guaranteed the project’s environmental sustainability, while the on-site training of the local community prepared its members for the continued maintenance of the road, thus investing the project with social sustainability.

Discrete Element Modeling of a 3D Scale Silo With Hopper

The discrete element method (DEM) is a numerical technique widely used to study the behavior of granular materials. It has proven to be reliable and effective in simulating many flow scenarios as well as the interaction between granular materials and the physical elements of the machinery or the physical system where they are contained.

Effects of different snow load arrangements on steel silo roof structures

Large diameter steel silos usually require a beam structure to support rooftop inspection gangways and resist loads derived from the snow and wind actions. The existence of localized overloads caused by drifted snow on roofs as a consequence of the wind action has been reported in the literature. European standard EN 1991-1-3 also considers the need of taking into account asymmetric patterns for snow loads calculation. However, conical roofs are not included in the specific list of cases considered by this standard. The present work compares the normal stresses and displacements produced in a conical steel silo roof structure by applying balanced loads distributed on the whole roof and unbalanced loads applied on a roof sector. Experimental measurements and a three-dimensional beam model developed by the authors have been used to predict the stresses and vertical displacements of a metal silo roof structure measuring 18.34 m in diameter. The results show that the existence of an asymmetric load pattern produces higher normal stresses (up to 23%) and vertical displacements (up to 50%) than those derived from balanced loads, for any similar load per beam considered.

Computational Methods for the Design of Formworks Used in Rural Works

Formworks play an important role in the support of lateral pressures exerted by fresh concrete on rural infrastructure works such as bunker silos, earth retaining walls or bridges in low volume roads. Traditionally, these elements have been designed assuming a non-viscous fluid behavior for the fresh concrete. Nevertheless, this procedure tends to overestimate the lateral pressures because the internal friction of the material and the existing friction between the material and the formwork wall are not considered. So, significant overpressures can be detected for high formworks.