In order to monitor and forecast the deformation of the brick-concrete building, by taking a brick-concrete building as research object, fiber grating sensors were used to collect the monitoring data and double logari...In order to monitor and forecast the deformation of the brick-concrete building, by taking a brick-concrete building as research object, fiber grating sensors were used to collect the monitoring data and double logarithmic curve of limit value characteristic and monitoring data were obtained based on the fractal theory. Constant dimension fractal method cannot be used to analyze the data directly. With the method of variable dimension fractal, we accumulate data, and the double logarithmic curve is smooth. Piecewise fractal dimensions are close. The outer interpolation method is used to calculate the fractal dimension of the next point and then back calculate the vertical displacement. The relative errors are calculated by comparing the forecast values and monitoring values, and the maximum relative error is 5.76%. The result shows that the fractal theory is suitable to use in the forecast of the deformation and the accuracy is good.展开更多
In order to improve the quality of the project, we adopt the intelligent compaction control system and collect CMV values through experiments. In the experiment using finite element simulation software to simulate and...In order to improve the quality of the project, we adopt the intelligent compaction control system and collect CMV values through experiments. In the experiment using finite element simulation software to simulate and analyze. From the simulation results to analyze the road surface displacement and stress trends, derived from the displacement of the pressed material in the fifth pass, the sixth pass is almost the same, the rate of change close to 0, can be considered pressed material has the desired pressure.?The actual degree is in good agreement with the actual compaction of sand filling, indicating that the compaction state of the pressed material can also be verified from the stress angle of the pressed material. The stress change from the weak vibration to the strong vibration load increases first and then decreases rapidly, and the reduction of strong vibration is more obvious. Therefore, the simulation result also shows that the strong vibration has the better compaction effect than the weak vibration.展开更多
As a highly strained small molecule,[1.1.1]propellane has been widely used in various synthetic transformations owing to the exceptional reactivity of the central bond between the two bridgehead carbons.Utilizing stra...As a highly strained small molecule,[1.1.1]propellane has been widely used in various synthetic transformations owing to the exceptional reactivity of the central bond between the two bridgehead carbons.Utilizing strain-release approaches,the rapid development of strategies for the construction of bicyclo[1.1.1]pentane(BCP)and cyclobutane derivatives using[1.1.1]propellane as the starting material has been witnessed in the past few years.In this review,we highlight the most recent advances in this field.Accordingly,the reactivity of[1.1.1]p ropellane can be divided into three pathways,including radical,anionic and transition metal-catalyzed pathways under appropriate conditions.展开更多
文摘In order to monitor and forecast the deformation of the brick-concrete building, by taking a brick-concrete building as research object, fiber grating sensors were used to collect the monitoring data and double logarithmic curve of limit value characteristic and monitoring data were obtained based on the fractal theory. Constant dimension fractal method cannot be used to analyze the data directly. With the method of variable dimension fractal, we accumulate data, and the double logarithmic curve is smooth. Piecewise fractal dimensions are close. The outer interpolation method is used to calculate the fractal dimension of the next point and then back calculate the vertical displacement. The relative errors are calculated by comparing the forecast values and monitoring values, and the maximum relative error is 5.76%. The result shows that the fractal theory is suitable to use in the forecast of the deformation and the accuracy is good.
文摘In order to improve the quality of the project, we adopt the intelligent compaction control system and collect CMV values through experiments. In the experiment using finite element simulation software to simulate and analyze. From the simulation results to analyze the road surface displacement and stress trends, derived from the displacement of the pressed material in the fifth pass, the sixth pass is almost the same, the rate of change close to 0, can be considered pressed material has the desired pressure.?The actual degree is in good agreement with the actual compaction of sand filling, indicating that the compaction state of the pressed material can also be verified from the stress angle of the pressed material. The stress change from the weak vibration to the strong vibration load increases first and then decreases rapidly, and the reduction of strong vibration is more obvious. Therefore, the simulation result also shows that the strong vibration has the better compaction effect than the weak vibration.
基金the National Natural Science Foundation of China(Nos.21672037 and 21532001)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01005)。
文摘As a highly strained small molecule,[1.1.1]propellane has been widely used in various synthetic transformations owing to the exceptional reactivity of the central bond between the two bridgehead carbons.Utilizing strain-release approaches,the rapid development of strategies for the construction of bicyclo[1.1.1]pentane(BCP)and cyclobutane derivatives using[1.1.1]propellane as the starting material has been witnessed in the past few years.In this review,we highlight the most recent advances in this field.Accordingly,the reactivity of[1.1.1]p ropellane can be divided into three pathways,including radical,anionic and transition metal-catalyzed pathways under appropriate conditions.
