In this document, seismic vulnerability and load carrying capacity analyses are presented for a bridge in Colombia after monitoring by means of reliability of structures. Results of this work are part of a new methodology to evaluate existing bridges carried out though a partnership among University – Private Companies – and Goverment. This study helps in decision making on the priority of rehabilitation tasks. This study included: dynamic characterization of natural vibrations of the bridge; data logging of inner forces due to traffic by using LVDT´s and strain gages technology; evaluation of actual forces to be compared to allowed stresses, dynamic and static structural modelling. Also, a seismic hazard and dynamic response of the local area of the bridge was developed and nine (9) different response spectra were obtained, each one varying its return period. It was found that the bridge towers have a larger failure probability than that allowed by the Codes. This produced an inmediate strengthening of the bridge.
Rev. ing. constr. [online]. 2008, vol.23, n.3, pp. 125-144. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732008000300001
This article describes the conception process, research development and implementation process at the laboratory level of a masonry unit with top and bottom semiovoid chock and made using recycled newspaper and paste of yucca starch. The devel ped implementation process has been used to make a set of masonry units to build walls. The article presents a methodology related to the constructive process of the walls in the real constructive context. This methodology was used to build 6 walls for characterization of the mechanical behaviour at two levels: axial compression and diagonal tension (shear). A discussion about the behaviour of the wall speciments and conclusions about the behaviour in the real context are presented. Finally, a feasibility analysis related to the structural application of the walls in the construction field of the civil engineering is argued.
Rev. ing. constr. [online]. 2008, vol.23, n.3, pp. 145-154. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732008000300002
Some part of the stock of social housing in Brazil has deteriorted due to lack of maintenance. The depreciation of these constructions, especially in the case of housing projects, reduces the quality of environment, with social and economic consequences for inhabitants, and also for the region. Building renewal is an important action to recover the lost quality of the life. The increase in life time of housing may also reduce the construction and demolition waste production. One of the most important aspects is the façade, which influences the value of the property and the perception of the society about the inhabitants. This work presents a study of improving and façade renewal of social housing in São Leopoldo, a southern Brazilian city.
Rev. ing. constr. [online]. 2008, vol.23, n.3, pp. 155-162. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732008000300003
This work seeks the application of solidification/stabilization techniques to contaminated soils analyzing specifically de physical behavior of the soil through oily sludge industrial residues and the application of that technique had an encapsulate agent, the Portland cement CP V–ARI. The tests were carried out according to NBR 13.554 (1996), and they aimed to study the level of degradation and the vulnerability of the material with several combinations of cement and acidic oily sludge as well as study their volumetric variations. Starting from the results, it is possible to observe that the larger the contamination the larger the mass loss; however the larger the amount of cement, the smaller the mass loss and the more stable the volumetric variation.
Rev. ing. constr. [online]. 2008, vol.23, n.3, pp. 163-170. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732008000300004
The very high concrete strength and durability achieved in high and ultra-high-performance concrete is associated with a very dense matrix, accomplished through the use of high volumes of very fine mineral additions, such as fly ash, silica-fume, metakaolin and ground quartz sand. The paper reports on a study where a finely ground lime-pozzolan binder (LPB) is used as active mineral addition in concrete. The very fine lime particles, having size between 0.1-lOum, can fill the gaps between cement grains, while the larger pozzolan particles, having size between 10-lOQim, can fill the gaps between fine aggregate grains; this results in a much denser matrix. The addition of lime during concrete mixing also increases the Ca+2 and OH ion concentration, which results in a better and faster hydration of both ordinary portland cement (OPC) and pozzolanic reaction products. The use of LPB as an active addition in some ultra-high performance concretes could lowe the cost of the product for equivalent strength and durability performance, through the use of less cement, thus improving the ecologic profile of the material. Results from an initial series of tests are examined in this paper; further testing is required to establish the benefits of the use of LPC in High Performance Concrete. Examples of applications of this work in concretes are also presented.
Rev. ing. constr. [online]. 2008, vol.23, n.3, pp. 171-178. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732008000300005
This paper presents a study that proposes the use of bamboo as a new laminated wood technology. The technology uses pressed fabrics of bamboo placed in orthogonal directions to build mat boards that can replace wood in certain structural elements. Bamboo mat boards, made with Bambusa Vulgaris Schrab using different temperatures and pressure during fabrication, are characterized in the lab by means of mechanical testing.
Rev. ing. constr. [online]. 2008, vol.23, n.3, pp. 179-186. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732008000300006
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