The key technologies of precision blasting were put forward based on the characteristics of urban via- duct blasting demolition in complicated surroundings. Initial bending instability mechanics model of reinforcing s...The key technologies of precision blasting were put forward based on the characteristics of urban via- duct blasting demolition in complicated surroundings. Initial bending instability mechanics model of reinforcing steel bar frame of blasting fragmented pier and sequenced collapsed dynamic model were established for quanti- tative blasting design. Technologies of water pressure blasting were applied in multi-cell box girder fragmenta- tion. The detonating network of non-electric duplication crossover was adopted for the safety and reliability of ultra-long delay. The rationality of blasting scheme and parameters were validated by physical model test. Harm- ful effects were forecasted and controlled by integrated protective technologies. Specialization, cooperation, pre- cision, execution (SCPE) project management method was put forward for precision management. The key tech- nologies of precision demolition blasting can provide reference for similar proiects.展开更多
The paper looks at some bridge structures from ancient aqueducts to the most recent viaducts since people have always built structures that help them to cross terrain obstacles such as rivers, ravines and hills. Their...The paper looks at some bridge structures from ancient aqueducts to the most recent viaducts since people have always built structures that help them to cross terrain obstacles such as rivers, ravines and hills. Their primary goal has functionality and efficiency rather than aesthetic considerations and, yet from a time perspective, they still impress with their beauty and perfection. Gradually, architects began to take care of the form of bridges, as in the case of the Rialto Bridge in Venice. Nowadays, the most renowned architects, with Norman Foster in the lead, take up the design of bridge "architecture". Although technical solutions remain top priority, aesthetic qualities are widely recognized and appreciated.展开更多
文摘The key technologies of precision blasting were put forward based on the characteristics of urban via- duct blasting demolition in complicated surroundings. Initial bending instability mechanics model of reinforcing steel bar frame of blasting fragmented pier and sequenced collapsed dynamic model were established for quanti- tative blasting design. Technologies of water pressure blasting were applied in multi-cell box girder fragmenta- tion. The detonating network of non-electric duplication crossover was adopted for the safety and reliability of ultra-long delay. The rationality of blasting scheme and parameters were validated by physical model test. Harm- ful effects were forecasted and controlled by integrated protective technologies. Specialization, cooperation, pre- cision, execution (SCPE) project management method was put forward for precision management. The key tech- nologies of precision demolition blasting can provide reference for similar proiects.
文摘The paper looks at some bridge structures from ancient aqueducts to the most recent viaducts since people have always built structures that help them to cross terrain obstacles such as rivers, ravines and hills. Their primary goal has functionality and efficiency rather than aesthetic considerations and, yet from a time perspective, they still impress with their beauty and perfection. Gradually, architects began to take care of the form of bridges, as in the case of the Rialto Bridge in Venice. Nowadays, the most renowned architects, with Norman Foster in the lead, take up the design of bridge "architecture". Although technical solutions remain top priority, aesthetic qualities are widely recognized and appreciated.