The work shows a summary of the most significant shells foundations built in Cuba in the last decades and the developments related to these in term of methods of calculation of plates and shells of complex geometry using reference surfaces and reference bodies, from the generalization of the projected solicitations method (Pücher, 1934) with the use of referential surfaces (Hernández, 1970) and other developments made in the mechanics of deformable solid by the Method of Duality (Rianitsiyn, 1974; Castañeda, 1993) and the Static-Geometric Analogy in the mechanics of the deformable solid (Castañeda, 1985).It also includes a summary of the research developed in recent years on the stress-strain states of soil under and inside shell foundations for chimneys of 74.5 m in sugar industries (Cobelo, 2004), comparative studies made of these with the use of the FEM (González, 2010) and other research projects currently running (Álvarez, 2010 ).

Rev. ing. constr. [online]. 2011, vol.26, n.3, pp. 245-268. ISSN 0718-5073.  http://dx.doi.org/10.4067/S0718-50732011000300001

The paper exposes the results of a study, at macro structural level, on the influence of the calcite grinding process fineness on the red ceramic bricks following properties: Compressive strength, Density, Absorption and Durability, though the performance of physical – mechanical and accelerated aging tests, when this is added in an amount inferior to the 10% in relation with the clay weight. It is proved that when this admixture is ground until fineness between 72 m and 150 m, the above mentioned properties are not affected, however it doesn’t occur this way when it is ground until a particle size of 297m. The carried out study, demonstrates that with this specific surface, the calcite addition affects the red ceramic bricks physical-mechanical properties as well as their durability.

Rev. ing. constr. [online]. 2011, vol.26, n.3, pp. 269-283. ISSN 0718-5073.  http://dx.doi.org/10.4067/S0718-50732011000300002

The MSD -musculoskeletal disorders- represent 45% of labour injuries. Specifically, construction workers involved in the different activities linked to steel reinforcement for an insitu concrete are exposed to a high rate of such injuries. This paper reviews in detail the physical risks of the iron worker, installing steel reinforcement for an insitu concrete pour. This study has revealed that the Spanish legislation, enforced since 1997 (transposing the European Directive on the implementation of minimum safety and health requirements at temporary or mobile construction sites) is not correcting the multiple musculoskeletal risk factors of these workers. It’s proposed for the analysis of such risks musculoskeletal, the use of different ergonomic methodologies. In one hand, the load handling guide from the Spanish National Health and Safety Institute, and in the other, the method ERGO/ IBV, developed by the Biomecanics Institute of Valencia for the repetitive tasks analysis. The use of these tools allows the design of new working methods that reduce the risks discussed. Subsequently, after the identification of the large number of risks musculoskeletals, it’s defined a set of better practices for these workers, exposed to very demanding work conditions and with low culture of prevention.

Rev. ing. constr. [online]. 2011, vol.26, n.3, pp. 284-298. ISSN 0718-5073.  http://dx.doi.org/10.4067/S0718-50732011000300003

This article presents an experimental study on the variation with depth of the stresses due to lateral earth pressure on a wall retaining a soil reinforced with geogrids. To this end, an apparatus was designed and constructed especially tailored for performing lateral earth pressure tests under plain strain conditions. The experimental apparatus and the measurement instruments as well as the soil and the sample preparation and the geogrids used, are described. In a first stage of research, samples without reinforcing are tested and the results are compared with those from classic earth pressure theories. Subsequently, results from lateral earth pressure tests in soils reinforced with one, two, three and four geogrids are presented. It is concluded that the inclusion of geogrids as soil reinforcement reduces the earth pressure on the retaining structure. This lateral earth pressure reduction is approximately of 25% when one geogrid is used, 50% with two or three geogrids and 75% with four geogrids for the spacing, surcharges and displacement increments used. It was possible to identify that the lateral earth pressure distribution with depth not only does not follow a triangular variation, but it develops stress arching in the soil and between the geogrids.

Rev. ing. constr. [online]. 2011, vol.26, n.3, pp. 299-320. ISSN 0718-5073.  http://dx.doi.org/10.4067/S0718-50732011000300004

This research determines the axle loads of trucks traveling on a bridge located in one of the most important corridors of Colombia, using the technique of control BWIM (Bridge Weight in Motion), not used before in the country. Our research group developed a Genetic Algorithm based in a trial test, implementation and monitoring to the bridge called Boquerón of Colombian Highways (Bogota – Villavicencio). For such an effort, four girders were monitored by data acquisition electronics joined by an electronic traffic log device by lane accompanied of laboratory testing for materials. Model calibration was performed by mathematical approach of in-situ influence lines compared to those obtained by modeling, giving as outcome loads of moving trucks over the bridge. In addition, we developed a computational tool, able to represent with reasonable accuracy the moving loads.

Rev. ing. constr. [online]. 2011, vol.26, n.3, pp. 321-352. ISSN 0718-5073.  http://dx.doi.org/10.4067/S0718-50732011000300005

There has not been implemented, in Mexico, a model for the management of technological innovation, which refers to the creation or modification of a product or process in a practical way that is useful to generate economic benefits by introducing the innovation to the market. This has led to isolated and irregular efforts in this area; however, the real state sector has recognized the need to implement such management of technological innovation in order to achieve differentiation. Management of technological innovation must be understood as the process to organize resources in order to create knowledge, processes and products. This article is an effort to implement a Model for the Management of Technological Innovation (MGIT) applied to the housing sector. MGIT takes account of the trends of development in building technologies and the features of this productive sector. The purpose of this effort is to reduce time and cost on the process of seeking for technological innovation. The MGIT is validated with a case of application for the creation of a new system of building facades for residential housing.

Rev. ing. constr. [online]. 2011, vol.26, n.3, pp. 353-368. ISSN 0718-5073.  http://dx.doi.org/10.4067/S0718-50732011000300006