Abstract: The present disclosure relates to an ERT/ECT dual-modality combined three-dimensional sensor. A cover box is sheathed with a shielding box, a plurality of small round holes are formed in the top surface and the side surfaces of the cover box, ERT electrodes are arranged in the small round holes, and ECT electrodes are arranged at the outer sides of the ERT electrodes. The ERT electrodes are connected to an ERT data acquisition box via electrode leads, and the ECT electrodes are connected to an ECT data acquisition box via the electrode leads. An integrated cuboid design in line with the concrete structure is employed. Meanwhile, the dimensions, combination modes, placement modes and positions, supporting structures, shielding devices, electrode leads and leading-out modes of two sets of electrode arrays are subjected to comprehensive optimization design to achieve three-dimensional visual nondestructive monitoring of the moisture intrusion process in the concrete structure.

Abstract: The present disclosure relates to an ERT/ECT dual-modality combined three-dimensional sensor. A cover box is sheathed with a shielding box, a plurality of small round holes are formed in the top surface and the side surfaces of the cover box, ERT electrodes are arranged in the small round holes, and ECT electrodes are arranged at the outer sides of the ERT electrodes. The ERT electrodes are connected to an ERT data acquisition box via electrode leads, and the ECT electrodes are connected to an ECT data acquisition box via the electrode leads. An integrated cuboid design in line with the concrete structure is employed. Meanwhile, the dimensions, combination modes, placement modes and positions, supporting structures, shielding devices, electrode leads and leading-out modes of two sets of electrode arrays are subjected to comprehensive optimization design to achieve three-dimensional visual nondestructive monitoring of the moisture intrusion process in the concrete structure.

Abstract: A device and method for monitoring freezing-thawing damage of an underwater concrete member in situ. A main structure includes an upper link, concrete member, transverse sealed box, longitudinal sealed box, movable guide rod, probe launching box, multichannel data collector, frequency modulation transmitter, computer, auxiliary wheels, lower link, and a wireless temperature sensor. A process includes four steps: launching of a probe, collection of data, calculation of an elastic modulus, and evaluation of freezing-thawing damage.

Abstract: The present application belongs to the technical field of monitoring of durability of concrete, and particularly relates to a method for optimizing a structure of an electrical capacitance tomography sensor and analyzing an electromagnetic field. A specific process of the method includes eight steps: parameter setting, geometric setting, material setting, mesh generation, physical field setting, solution, sensor structure optimization and calculation of electromagnetic field distribution. The method proposes a new concept for solving a forward problem of an ECT system based on COMSOL software. After modeling is completed, uniformity of a sensitive field of the ECT sensor is analyzed according to calculation results, and structural parameter values of components of the ECT sensor are adjusted to seek an optimal design scheme.

Abstract: An apparatus and a method for testing water absorption of concrete in a direction parallel with load applying direction are provided. The apparatus includes a loading device, a water filling device, and a monitoring device. The loading device includes an upper support plate and a lower support plate connected with the upper support plate via multiple threaded rods, and a space for placing a concrete specimen formed between the upper support plate and the lower support plate. The water filling device includes a water filling cylinder having a side connected with a water supply tank via an inlet pipe, and another side connected with a water storage tank via an outlet pipe. The monitoring device includes a mass sensor arranged under the water storage tank and a strain gauge for detecting change of stress of the concrete specimen.

Abstract: The present application belongs to the technical field of monitoring of durability of concrete, and particularly relates to a method for optimizing a structure of an electrical capacitance tomography sensor and analyzing an electromagnetic field. A specific process of the method includes eight steps: parameter setting, geometric setting, material setting, mesh generation, physical field setting, solution, sensor structure optimization and calculation of electromagnetic field distribution. The method proposes a new concept for solving a forward problem of an ECT system based on COMSOL software. After modeling is completed, uniformity of a sensitive field of the ECT sensor is analyzed according to calculation results, and structural parameter values of components of the ECT sensor are adjusted to seek an optimal design scheme.

Abstract: A device and method for monitoring freezing-thawing damage of an underwater concrete member in situ. A main structure includes an upper link, concrete member, transverse sealed box, longitudinal sealed box, movable guide rod, probe launching box, multichannel data collector, frequency modulation transmitter, computer, auxiliary wheels, lower link, and a wireless temperature sensor. A process includes four steps: launching of a probe, collection of data, calculation of an elastic modulus, and evaluation of freezing-thawing damage.

Abstract: The disclosure relates to a device and method for a dry-wet cycle simulation test of concrete in a tidal zone and a splash zone. A main structure includes a liquid storage tank, a test chamber, a communicating pipe, air holes of the liquid storage tank, air holes of the test chamber, ceiling fans, steel pipes, a support frame, an upper water level sensor, a lower water level sensor, a temperature and humidity sensor, a temperature sensor, a chamber body support, a communication valve, a pipe support, a water inlet pump, a water inlet valve, a water outlet pipe, a water outlet pump, a water outlet valve, spray water pipes, spray heads, and a control box. The control box can control and record test parameters in real time, so that the boundary between the tidal zone and the splash zone is clear.

Abstract: An apparatus and a method for testing water absorption of concrete in a direction parallel with load applying direction are provided. The apparatus includes a loading device, a water filling device, and a monitoring device. The loading device includes an upper support plate and a lower support plate connected with the upper support plate via multiple threaded rods, and a space for placing a concrete specimen formed between the upper support plate and the lower support plate. The water filling device includes a water filling cylinder having a side connected with a water supply tank via an inlet pipe, and another side connected with a water storage tank via an outlet pipe. The monitoring device includes a mass sensor arranged under the water storage tank and a strain gauge for detecting change of stress of the concrete specimen.

Abstract: The disclosure relates to a device and method for a dry-wet cycle simulation test of concrete in a tidal zone and a splash zone. A main structure includes a liquid storage tank, a test chamber, a communicating pipe, air holes of the liquid storage tank, air holes of the test chamber, ceiling fans, steel pipes, a support frame, an upper water level sensor, a lower water level sensor, a temperature and humidity sensor, a temperature sensor, a chamber body support, a communication valve, a pipe support, a water inlet pump, a water inlet valve, a water outlet pipe, a water outlet pump, a water outlet valve, spray water pipes, spray heads, and a control box. The control box can control and record test parameters in real time, so that the boundary between the tidal zone and the splash zone is clear.

Abstract: An assembled slab-type steel-wood composite joint, includes a steel-wood composite column, square wood beams, connecting assemblies for connecting the steel-wood composite column and the square wood beams, and wood slabs connected to and supported by the steel-wood composite column, the square wood beams and the connecting assemblies. The steel-wood composite column includes a hollow cross-shaped outer square wood column, and square blocks are integrally formed on the outer square wood column; and a steel sleeve is inlaid in the outer square wood column, an inner wood column is inlaid in the steel sleeve, column vertical steel bars penetrate through the inner wood column, horizontal steel bars penetrate through the square blocks and are fixedly connected to the steel sleeve, and threads are arranged at the ends of the horizontal steel bars.

Abstract: An assembled slab-type steel-wood composite joint, includes a steel-wood composite column, square wood beams, connecting assemblies for connecting the steel-wood composite column and the square wood beams, and wood slabs connected to and supported by the steel-wood composite column, the square wood beams and the connecting assemblies. The steel-wood composite column includes a hollow cross-shaped outer square wood column, and square blocks are integrally formed on the outer square wood column; and a steel sleeve is inlaid in the outer square wood column, an inner wood column is inlaid in the steel sleeve, column vertical steel bars penetrate through the inner wood column, horizontal steel bars penetrate through the square blocks and are fixedly connected to the steel sleeve, and threads are arranged at the ends of the horizontal steel bars.