The present invention discloses a preparation method for a surface molding film of a PVC-based stone plastic composite board, including: surface activation treatment of the PVC-based stone plastic composite board: preparation of an activated putty, coarse roughening of a substrate surface, application and solidification of the activated putty, and fine roughening of the substrate surface; preparation of a PMMA slurry; and surface film forming of the PVC-based stone plastic composite board. The PVC-based stone plastic composite board coated with a PMMA film is obtained by cold pressing and shaping in a mold, tightening up a clamp, solidifying at low temperature, treating at high temperature, cooling and demolding. The PVC-based stone plastic composite board coated with the PMMA film prepared by the present invention can avoid the problems of large investment in production lines and equipment and high production costs involved in the production of floorboards by the conventional surface printing and surface laminating technologies, to partially replace composite floorboards, stone, acrylic panels, and curtain wall panels, etc. currently popular in the market, and provide a new path for the high additional utilization of waste.

The present invention discloses a preparation method for a surface molding film of a PVC-based stone plastic composite board, including: surface activation treatment of the PVC-based stone plastic composite board: preparation of an activated putty, coarse roughening of a substrate surface, application and solidification of the activated putty, and fine roughening of the substrate surface; preparation of a PMMA slurry; and surface film forming of the PVC-based stone plastic composite board. The PVC-based stone plastic composite board coated with a PMMA film is obtained by cold pressing and shaping in a mold, tightening up a clamp, solidifying at low temperature, treating at high temperature, cooling and demolding. The PVC-based stone plastic composite board coated with the PMMA film prepared by the present invention can avoid the problems of large investment in production lines and equipment and high production costs involved in the production of floorboards by the conventional surface printing and surface laminating technologies, to partially replace composite floorboards, stone, acrylic panels, and curtain wall panels, etc. currently popular in the market, and provide a new path for the high additional utilization of waste.

A method of sealing propagating cracks in a sensor-laden cement sheath comprising the steps of monitoring an electrical resistivity of the sensor-laden cement sheath to produce a measured value, wherein the sensor-laden cement sheath comprises a conductive sensor, an on-demand expanding agent, and a cement, activating a heat source when the measured value of the electrical resistivity is greater than an activation threshold, increasing a temperature of the sensor-laden cement sheath with the heat source to an activation temperature, wherein the activation temperature is operable to initiate a reaction between the on-demand expanding agent and water, wherein the activation temperature is greater than a formation temperature, reacting the on-demand expanding agent with water to produce a swelled agent, wherein the swelled agent occupies a greater volume than the on-demand expanding agent, and sealing the propagating cracks in the sensor-laden cement sheath with the swelled agent.

A method of sealing propagating cracks in a sensor-laden cement sheath comprising the steps of monitoring an electrical resistivity of the sensor-laden cement sheath to produce a measured value, wherein the sensor-laden cement sheath comprises a conductive sensor, an on-demand expanding agent, and a cement, activating a heat source when the measured value of the electrical resistivity is greater than an activation threshold, increasing a temperature of the sensor-laden cement sheath with the heat source to an activation temperature, wherein the activation temperature is operable to initiate a reaction between the on-demand expanding agent and water, wherein the activation temperature is greater than a formation temperature, reacting the on-demand expanding agent with water to produce a swelled agent, wherein the swelled agent occupies a greater volume than the on-demand expanding agent, and sealing the propagating cracks in the sensor-laden cement sheath with the swelled agent.

The present invention discloses a preparation method for a surface molding film of a PVC-based stone plastic composite board, including: surface activation treatment of the PVC-based stone plastic composite board: preparation of an activated putty, coarse roughening of a substrate surface, application and solidification of the activated putty, and fine roughening of the substrate surface; preparation of a PMMA slurry; and surface film forming of the PVC-based stone plastic composite board. The PVC-based stone plastic composite board coated with a PMMA film is obtained by cold pressing and shaping in a mold, tightening up a clamp, solidifying at low temperature, treating at high temperature, cooling and demolding. The PVC-based stone plastic composite board coated with the PMMA film prepared by the present invention can avoid the problems of large investment in production lines and equipment and high production costs involved in the production of floorboards by the conventional surface printing and surface laminating technologies, to partially replace composite floorboards, stone, acrylic panels, and curtain wall panels, etc. currently popular in the market, and provide a new path for the high additional utilization of waste.

The present invention discloses a preparation method for a surface molding film of a PVC-based stone plastic composite board, including: surface activation treatment of the PVC-based stone plastic composite board: preparation of an activated putty, coarse roughening of a substrate surface, application and solidification of the activated putty, and fine roughening of the substrate surface; preparation of a PMMA slurry; and surface film forming of the PVC-based stone plastic composite board. The PVC-based stone plastic composite board coated with a PMMA film is obtained by cold pressing and shaping in a mold, tightening up a clamp, solidifying at low temperature, treating at high temperature, cooling and demolding. The PVC-based stone plastic composite board coated with the PMMA film prepared by the present invention can avoid the problems of large investment in production lines and equipment and high production costs involved in the production of floorboards by the conventional surface printing and surface laminating technologies, to partially replace composite floorboards, stone, acrylic panels, and curtain wall panels, etc. currently popular in the market, and provide a new path for the high additional utilization of waste.

A precast concrete beam is provided in construction of a long span bridge structure. The beam is formed of a plurality of aligned modular elements each formed of prestressed UHPC mix as a unitary body. The UHPC mix includes discontinuous fibers distributed randomly throughout a concrete matrix. Each modular element is aligned modular and connected by an epoxy grout to adhering adjacent element joints. Finally, post-tensioning of the entire beam reinforces and affixes the plurality of aligned modular elements into a single long span beam.

A precast concrete beam is provided in construction of a long span bridge structure. The beam is formed of a plurality of aligned modular elements each formed of prestressed UHPC mix as a unitary body. The UHPC mix includes discontinuous fibers distributed randomly throughout a concrete matrix. Each modular element is aligned modular and connected by an epoxy grout to adhering adjacent element joints. Finally, post-tensioning of the entire beam reinforces and affixes the plurality of aligned modular elements into a single long span beam.