In the United States,more than 94%highways are paved with asphalt materials and placing crack sealant materials has been a common pavement maintenance for decades.Crack sealing treatment includes the use of a router t...In the United States,more than 94%highways are paved with asphalt materials and placing crack sealant materials has been a common pavement maintenance for decades.Crack sealing treatment includes the use of a router to create a reservoir on the intended cracks whereas crack filling is given without doing any modification to the crack wall.Although the initial cost of crack sealing is higher,it is expected to have a longer service period compared to crack filling.There is little research on comparison of short and long term cost effectiveness between these two treatments using the real field cost data analysis.In this study four test sites in Texas were treated with crack filling and sealing using the same sealant material and finishing technique.Cost effectiveness of both treatments was measured in terms of initial,annual average and life cycle cost based on the cost inputs during construction.In general,the results of this study indicated that(1)on an average approximately 45%initial cost increase was estimated with the two routing configurations of crack sealing;(2)material and labor cost is found to have the most significant effect on the higher initial cost of crack sealing compared to other associated costs;(3)annual average and life cycle costs have shown that crack sealing is more cost effective pavement maintenance compared to crack filling over a long period of time;(4)agency cost is observed to be reduced by approximately 24%with crack sealing treatment based on the35 year analysis period.展开更多
Costs and losses induced by possible future extreme environmental conditions and difficulties in repairing post yielding damage strongly suggest the need for proper consideration in design rather than just life loss ...Costs and losses induced by possible future extreme environmental conditions and difficulties in repairing post yielding damage strongly suggest the need for proper consideration in design rather than just life loss prevention. This can be addressed through the development of design methodology that balances the initial cost of the very large floating structure (VLFS) against the expected potential losses resulting from future extreme wave induced structural damage. Here, the development of a methodology for determining optimal, cost effective design will be presented and applied to a VLFS located in the Tokyo bay. Optimal design criteria are determined based on the total expected life cycle cost and acceptable damage probability and curvature of the structure, and a set of sizes of the structure are obtained. The methodology and applications require expressions of the initial cost and the expected life cycle damage cost as functions of the optimal design variables. This study includes the methodology, total life cycle cost function, structural damage modeling, and reliability analysis.展开更多
In the urban residential building stock, a major proportion is constituted by low-rise individual buildings. In addition to cost, quality and duration, energy consumed for the project needs to be accounted in the deci...In the urban residential building stock, a major proportion is constituted by low-rise individual buildings. In addition to cost, quality and duration, energy consumed for the project needs to be accounted in the decision making process. Minimizing the cost of construction without compromising on the architectural and structural requirements is the primary objective of the residential buildings of stake-holders, especially the owners. The choice of structural system and the materials used for construction play a crucial role in this effort. This means that the use of expensive and/or voluminous materials such as cement, steel, masonry etc. is optimized. This could lead to significant reduction in embodied energy as well, if the choice of the structural system is prudently made. In this paper, an attempt has been made to quantify the cost and embodied energy benefits for a low-rise residential building by choosing two different structural systems, namely moment resisting framed (MRF) construction system and the partly load-bearing (PLB) system. The influence of choice of materials, contributing to reduction of cost and/or energy is discussed. It is clearly noticed that, when the structural system is re-configured as a PLB system from the existing MRF system there is significant reduction in cost and embodied energy without changing the architectural form.展开更多
基金TxDOTsupported by the Research Grant from KICT through the Korea Agency for Infrastructure Technology Advancement funded by the Ministry of Land,Infrastructure and Transport of the Korean government(Project No:18TBIP-C125410-02).
文摘In the United States,more than 94%highways are paved with asphalt materials and placing crack sealant materials has been a common pavement maintenance for decades.Crack sealing treatment includes the use of a router to create a reservoir on the intended cracks whereas crack filling is given without doing any modification to the crack wall.Although the initial cost of crack sealing is higher,it is expected to have a longer service period compared to crack filling.There is little research on comparison of short and long term cost effectiveness between these two treatments using the real field cost data analysis.In this study four test sites in Texas were treated with crack filling and sealing using the same sealant material and finishing technique.Cost effectiveness of both treatments was measured in terms of initial,annual average and life cycle cost based on the cost inputs during construction.In general,the results of this study indicated that(1)on an average approximately 45%initial cost increase was estimated with the two routing configurations of crack sealing;(2)material and labor cost is found to have the most significant effect on the higher initial cost of crack sealing compared to other associated costs;(3)annual average and life cycle costs have shown that crack sealing is more cost effective pavement maintenance compared to crack filling over a long period of time;(4)agency cost is observed to be reduced by approximately 24%with crack sealing treatment based on the35 year analysis period.
文摘Costs and losses induced by possible future extreme environmental conditions and difficulties in repairing post yielding damage strongly suggest the need for proper consideration in design rather than just life loss prevention. This can be addressed through the development of design methodology that balances the initial cost of the very large floating structure (VLFS) against the expected potential losses resulting from future extreme wave induced structural damage. Here, the development of a methodology for determining optimal, cost effective design will be presented and applied to a VLFS located in the Tokyo bay. Optimal design criteria are determined based on the total expected life cycle cost and acceptable damage probability and curvature of the structure, and a set of sizes of the structure are obtained. The methodology and applications require expressions of the initial cost and the expected life cycle damage cost as functions of the optimal design variables. This study includes the methodology, total life cycle cost function, structural damage modeling, and reliability analysis.
文摘In the urban residential building stock, a major proportion is constituted by low-rise individual buildings. In addition to cost, quality and duration, energy consumed for the project needs to be accounted in the decision making process. Minimizing the cost of construction without compromising on the architectural and structural requirements is the primary objective of the residential buildings of stake-holders, especially the owners. The choice of structural system and the materials used for construction play a crucial role in this effort. This means that the use of expensive and/or voluminous materials such as cement, steel, masonry etc. is optimized. This could lead to significant reduction in embodied energy as well, if the choice of the structural system is prudently made. In this paper, an attempt has been made to quantify the cost and embodied energy benefits for a low-rise residential building by choosing two different structural systems, namely moment resisting framed (MRF) construction system and the partly load-bearing (PLB) system. The influence of choice of materials, contributing to reduction of cost and/or energy is discussed. It is clearly noticed that, when the structural system is re-configured as a PLB system from the existing MRF system there is significant reduction in cost and embodied energy without changing the architectural form.
