This paper compares, from a sustainability perspective, the environmental impact of a masonry arris vault with respect to a reticulated reinforced concrete slab, using techniques based on the Life Cycle Assessment to quantify the energy used in the manufacturing process of materials and in the construction of the structure. It has been detected that the vault consumes 75% less energy in the construction process, it emits 69% less CO2 into the atmosphere, it has an average manufacturing cost for short spans similar to a conventional slab, but much lower when large spans have to be covered, and it generates 171% less packaging waste from works, but it needs a larger and more skilled labor force. This paper shows that the vaulted building fully meets the current sustainability requirements and that this construction technique can coexist with the technology characterizing today's society, resulting in a product with high economic, functional and energy performances.
Rev. ing. constr. [online]. 2012, vol.27, n.1, pp. 05-22. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732012000100001
The aim of this paper is to develop a simple model to assess structural vulnerability of buildings at a regional scale. This model was especially made for areas where current reports on damages of buildings do not exist. The method is based on the identification of the most influential characteristics associated with damage in building under the action of the effect effects of landslides. The evaluation of these characteristics was carried out by means of the determination of fourteen (14) parameters. A vulnerability degree and an importance value based on experts´ opinions were assigned to each of the 14 parameters. Due to the imprecision and subjectivity of the opinions, data was processed by means of fuzzy logic techniques. Once each one of the parameters was qualified, the qualifications of the parameters were related to their value of importance by means of a fuzzy factorial. The result of this relationship, according to techniques based on fuzzy set, is the building vulnerability index.
Rev. ing. constr. [online]. 2012, vol.27, n.1, pp. 23-39. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732012000100002
Natural ventilation has won popularity in recent times like an energy saving way for buildings. There are two fundamental principles of natural ventilation: natural draft by difference in temperature and wind strength. The article aims to analyze the aerodynamics of windcatcher and wind-extractor by computational fluid-mechanics, optimizing the geometry of these elements, and giving as a result of the work a simplified model to take account aeraulic calculation of air conditioning system. So, It has characterized a collection of wind-catchers; and have developed a guide for geometric design of wind-extractor, also several of them like a result of the work.
Rev. ing. constr. [online]. 2012, vol.27, n.1, pp. 40-56. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732012000100003
The present paper introduces the evolution of resilient modulus, permanent strain and fatigue life of an asphaltic concrete mixture exposed under weather conditions in Bogota D.C. (Colombia) during 47-48 months. Mixtures were elaborated by using two asphaltic cements (CA) made in Colombia: CA 80-100 and CA 60-70. Mixtures generally tend to increase their stiffness values after an exposure period, mainly due to hardening and ageing processes undergone by asphaltic binder. A stiffness gain leads to increase endurance against rutting phenomenon and fatigue life of the analyzed mixture employed to lay thick asphaltic layers on the pavement. Based on the resilient modulus evolution due to exposure under environmental conditions, an equation is proposed to approximately predict the evolution of fatigue life endured by a mixture.
Rev. ing. constr. [online]. 2012, vol.27, n.1, pp. 57-74. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732012000100004
Safety is one of the main issues that must be considered when evaluating the quality of service provided by a road. Therefore, skid resistance measurement procedures are quite important components of a road management system. Currently, many equipments and procedures are used to measure skid resistance in pavement surfaces, like British Pendulum, GripTester, SCRIM, among others. Skid resistance data collected with such devices is afterwards processed and compared against minimum threshold values, predefined for the road management procedures. However, to ensure an acceptable reliability and quality level of such results, continuous monitoring of measurement procedures and also revision and calibration of devices must be performed. In this paper, a general methodology is proposed, to be used as a quality control system for devices and skid resistance measurements. Such methodology has been designed by using checklists, and applying statistical concepts of repeatability and reproducibility. The methodology was therefore applied to evaluate the quality level achieved by skid resistance devices and measurement procedures used in Chile, with good results. The quality of the evaluation procedures included in the methodology were also verified applying Six-Sigma statistical analysis techniques, which contributed significatively to improve the proposed quality control system.
Rev. ing. constr. [online]. 2012, vol.27, n.1, pp. 75-92. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732012000100005
The development of the new 2011 Transportation Association of Canada (TAC) Pavement Asset Design and Management Guide (PADMG) began in September 2009. The project is a pooled fund study being sponsored by over twenty Canadian public agencies including all ten provincial Canadian Departments of Transportation, several major Canadian cities, several industry associations and the federal government. The effort is being lead by a Canadian consortium team composed of consultants and academics from across Canada. The consortium team is composed of a diverse group of practitioners who have experience across Canada in the various areas of expertise pertinent to this guide. The new 2011 PADMG will be an up-to-date, practical consolidation of Canadian pavement design and management practice for practicing engineers, managers and technicians. It will also be a valuable resource for college and university courses both in Canada and elsewhere. The guide will highlight key industry issues such as sustainability, climate change, and new innovations. The paper first provides a summary of findings from a stakeholder survey to determine current state-of-the-practice in Canada. Information collected in this survey covers the major practices areas in pavement design and management. There will be 15 chapters in the new guide ranging from discussions on the principles of asset management, to data requirements, sustainability, maintenance, materials, low and high volume road design and life cycle analysis of pavement designs. The draft 2011 PADMG has been submitted and the project will be completed by September 2011.
Rev. ing. constr. [online]. 2012, vol.27, n.1, pp. 93-111. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732012000100006