Abstract: The present disclosure provides a prestressed strengthening apparatus for a prefabricated highway bridge. The prestressed strengthening apparatus includes a first mounting frame in a length direction of a strengthening component. The first mounting frame is provided with a sliding table in a length direction, a sliding block of the sliding table is provided with a bi-directional hydraulic cylinder perpendicular to a width direction of the first mounting frame, output ends of the bi-directional hydraulic cylinder are provided with a first connecting block parallel to a height direction of the first mounting frame respectively, the first connecting blocks arranged on two sides are provided with a left sliding rod and a right sliding rod respectively, one end of the left sliding rod is slidably sleeved with one end of the right sliding rod, and a second connecting block, parallel to the first connecting blocks, is arranged at the other end of the left sliding rod and the right sliding rod respectively.

Abstract: The invention discloses a ground motion intensity measure optimization method for seismic response prediction. The method includes the following steps: (1) building a building damage database; (2) optimizing ground motion intensity measures; (3) constructing a machine learning model; and (4) predicting damage states. According to the method, a combination of optimal ground motion intensity measures is selected by an elastic-net algorithm, wherein the efficiency and practicability in a current selection criterion are updated based on the goodness of fit and regression coefficient of the elastic-net model, thereby avoiding an assumption that intensity measures and structure response need to obey a logarithmic linear relationship and the limitation of intensity measure dimensions in traditional methods. By using the combination of optimal ground motion intensity measures as input variables, the prediction accuracy can be remarkably improved, and meanwhile the number of samples required is reduced.

Abstract: An infrared ray gas burner comprises an ignition valve, a nozzle, an ejector, a furnace chamber, a porous combustion radiant panel and an ignition needle. An ignition nozzle is placed in the furnace chamber, a sundries baffle is provided in the furnace chamber below the porous combustion radiant panel and above the ignition nozzle and the ignition needle is set above the porous combustion radiant panel, so the gas for ignition ejected from the ignition nozzle quickly mixes with the air inside the furnace chamber, and the gas-air mixture escapes from fire holes of the porous combustion radiant panel above the ignition nozzle. The gas concentration of the mixed gas is relatively high and suitable for igniting, the main burner can be quickly ignited, there is no black smoke, obviously incomplete combustion, and it brings a high ignition rate.