Decision-making on economic maintenance of earthquake-resistant reinforced concrete structures
It is necessary to repair or reinforce earthquake-resistant reinforced concrete structures during their service time since their safety performance may gradually deteriorate due to environmental factors such as concrete carbonation, steel erosion, natural aging, or earthquake damage. This paper adopts a benefit-cost analysis and puts forward an economic decision-making method on preventive maintenance, pre-earthquake reinforcement, and post-earthquake repair and dismantling of structures, with consideration to earthquake damage accumulation, natural aging, and durability damage. It is of crucial theoretical significance and application value to the decision-making on the maintenance of structures.
Lifetime Bridge Maintenance Strategies Based on System Reliability
This study proposes a methodology for a system reliability-based condition evaluation of existing highway bridges. The approach is illustrated for an existing steel bridge located in Colorado, USA....
Accurate measurements of output characteristics and detonations of motorbike high-speed racing engine and their optimization at actual atmospheric conditions and combusted mixture composition
Abstract At a motorbike high speed racing engine there is very important an output engine characteristics which depends significantly on a detonation combustion rate, atmospheric conditions and a combusted mixture composition. The combustion process has got a relevant influence on a wear degree of main engine parts or on their damage eventually. The detonation combustion rate is very important because this kind of burning can be not only destructive but a useful phenomenon, as well. If the process of detonation burning is kept on a certain level, it can help significantly to the next increasing of an engine power output. In this article there is described the measurements of output characteristics of a high-speed racing engine which were performed by means of a data-recording system and the detonation combustion was evaluated using a quantitative method. The actual values of atmospheric conditions and the mixture composition were added to the measured values. Then the obtained values are compared visually with a damage degree of an engine piston caused by the detonation burning. The result is a limit value expressed in a number of detonation units related to a run distance interval of the vehicle driven by the high-speed racing engine. In framework of this run distance interval there is the process of detonation burning profitable. As well as it increases an engine power output and together it is not destructive with regard to engine design parts.