With the trend in procurement systems from the traditional competitive tender to negotiated tenderwith a consortium or joint venture company, there is a growing need for the management of risks to behandled with greater care and depth. There are two levels of risk handling in these comp/ex projects, onebetween consortia partners and the second between the consortium and the client. There is growing need tolink the risk management plan to the negotiation of contract to create a lasting partnership between theproject participants. Contracts negotiated in isolation to the risk management study results, if at allconducted, fail to allocate the risks to the parties most capable or willing to take those risks and managethem. Contractors have to adapt to the innovative, long-term type contract. This paper discusses themanagement strategies of contractors who are major stakeholders in such ventures using a case study model.
This paper discusses the effects of carbonation on the microstructure of portland cement concrete for longtermdurability applications. A class C40 concrete (characteristic compression strength between 40 MPa and 44 MPaon the 28th 2 th and 91st days, respectively.atmosphere after physical and mechanical characterization. It was observed that carbonation provoked a reduction of 5% to 12% of the concreteopen porosity accessible to water. Flexural strength values obtained after the carbonation tests revealed a decrease of12% and 25% in relation to the values obtained before tests on the 28day, according to Brazilian standard NBR 8953) was chosen for the experimental study of the carbonationeffects, from which test samples were molded for accelerated test under a 100%-CO
This paper briefly describes a global methodology to develope incremental equations for pavement distress prediction,which are very useful to evaluate in-service pavements. Such methodology is subsequently applied to model transverse jointfaulting in concrete pavements, considering joints without dowelbars. The results show that models obtained from statisticalregression of incremental distress data, compared with absolute distress models, seem to have very similar capacities tosimulate distress progression. However, the incremental equations developed in this study have many limitations caused bya large incidence of different error sources and by the lack of enough information of distress progression in the observedpavements.
A fundamental objective to design a habitable space is to assure the occupants thermal comfort, considering anenergy use compatible with the activities developed in this space. The social housing does not fulfill this objective in Chile,due to: (1) Housing design does not consider this objective; (2) a high percentage of housing has a reduced area (smallerthan 50 m2 2 2 2 (40%) in Santiago, and 90 kWh/año·m2 (24%) in Punta Arenas.for refrigeration). Therefore, thermal comfort conditions are not achieved. On the other hand, the application of integral thermal control strategies produces important reductions of thermal loads, above to 45kWh/año·mforheating and 76 kWh/año·m ) with a high rate of occupation; (3) thermal envelope (walls, slabs on grade, ceiling and windows) has low thermal insulation capacity. (4) Chilean Building Code does not demand requirements of envelope thermal insulation,except for ceiling (since 2000). This produces a reduction of users’ life quality and an inefficient use of energy resources inconditioning housing. The objective of this research was to evaluate the effect on heating and refrigeration loads of severalthermal control passive strategies, such as thermal insulation, windows orientation and size, and passive solar heating, inorder to establish recommendations for the design of social housing in Santiago, Concepción and Punta Arenas (heatingand/or cooling climates). PowerDOE, a building energy simulation software was used. The main results show importantheating and refrigeration loads for the housing without thermal control strategies (between 111 and 370 kWh/año·m
In this paper states and comments the importance of some topics considers in the Chilean Standard of ConcreteCores such as the decision to drilled cores of concrete, including all the process to obtain, prepare and test cores tofinally, evaluate the results. Additionally, thank to the gain experience, it complement with technical evidences andgive recommendations to take into account at the moment to realize diagnostics and conclusions respect all theactivities involve.
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