Cai Zhengyin

Bio: Cai Zhengyin is an academic researcher. The author has contributed to research in topics: Worm drive & Lateral earth pressure. The author has an hindex of 5, co-authored 10 publications receiving 40 citations.

Flap type wave generator system in high-gravity field

Abstract: A flap type wave generator system in a high-gravity field comprises a centrifugal machine system, a motor, a belt, a speed changer, a force conversion device, a flap device and a wave eliminating device, wherein a model box is arranged in a hanging basket of the centrifugal machine system, the wave generator system is arranged on the model box, the force conversion system is fixed on the upper surface of a top cover of the model box, the axial direction of the motor, the axial direction of a transmission shaft and the axial direction of the speed changer are perpendicular to the top cover of the model box, and the motor, the transmission shaft and the speed changer are arranged in parallel; the output of the motor passes through the transmission shaft and then is output by the speed changer through speed change to the input end of the force conversion device, the force conversion device converts the rotating motion output by the motor into the linear reciprocating motion which is then output to the second end of a flap, the flap device comprises the flap, a fixing plate and a support, the support is fixed on a base plate of the model box, the first end of the flap is connected with the fixing plate in a rotary mode, and the second end of the flap is connected with the output end of the force conversion device in a rotary mode. The mechanical driving flap type wave generator has the advantages of being high in control precision and good in wave generation frequency characteristic.

Adjustable position fixing installation device of soil pressure gauge

Abstract: An adjustable position fixing installation device of a soil pressure gauge is arranged on the periphery of the soil pressure gauge and characterized in that a hoop made of a rigid plate is arranged on the adjustable position fixing installation device, the thickness of the loop is equal to or smaller than that of the soil pressure gauge, the shape of the hoop corresponds to the shape of the periphery of the soil pressure gauge, and the size of the inside of the hoop is equal to or slightly greater than the dimension of the periphery of the soil pressure gauge. Two fixing reinforcing steel bars are fixed on the back surface of the hoop, hooks are arranged on ends of the two fixing reinforcing steel bars, and other ends of the fixing reinforcing steel bars incline to the direction of the back surface. By means of the adjustable position fixing installation device of the soil pressure gauge, interface type installation of the soil pressure gauge can be achieved conveniently and accurately, and the problem that the soil pressure gauge is easily covered with concrete when buried is solved, installation time is saved further, the 'survival rate' of the soil pressure gauge is increased, and installation cost is reduced. Furthermore, the adjustable position fixing installation device of the soil pressure gauge is an ideal device capable of overcoming the shortcoming in the prior art and has obvious economic benefit and social benefit.

Wave pressure sensor embedding device and method

Abstract: Disclosed is a wave pressure sensor embedding device and method. A wave pressure sensor is disposed in a protector. The wave pressure sensor embedding device is characterized in that the protector is composed of a combined sleeve and a directional base; the combined sleeve is structurally characterized in that a spring is fixed on a steel plate at the bottom end of a sleeve body; the steel plate at the bottom end of the sleeve body is provided with a lead hole; a guide wire is welded at the right end of the sleeve body. The directional base is structurally characterized by comprising two U-shaped guide slides, a connecting steel plate, a limit plate and four fixing supports; the U-shaped guide slides are disposed in parallel and are welded into an integrated base through the connecting plate; the limit plate is disposed inside the U-shaped guide slides; the fixing supports are welded on the upper and lower portions of the U-shaped guide slides respectively. The wave pressure sensor is insusceptible to hoisting of forms, a stress face of the sensor can be level with a bearing wave stressed wall, and the wave pressure sensor can be effectively protected from destruction from external force. The wave pressure sensor can be embedded highly successfully and positioned accurately, and measurement data is true and reliable.

Centrifugal model foundation soil layer consolidometer

Abstract: The invention discloses a centrifugal model foundation soil layer consolidometer which consists of a leveling device, a lever loading device, a guide force transmission device, a consolidation container and a framework, wherein the leveling device consists of a handwheel and a worm wheel and worm mechanism; the lever loading device comprises a horizontal lever, a connection device and a weight hanging disk; the connection device comprises a transverse shaft and eccentric transmission shafts arranged at two ends of the transverse shaft, wherein the eccentric transmission shafts consist of main body shafts and eccentric shafts; an eccentric hole is formed in one end of each main body shaft, and each eccentric shaft is arranged at the other end of the corresponding main body shaft; a turbine shaft is vertically arranged; the handwheel drives a worm through a gear to drive the turbine shaft to move up and down; the connection device and the weight hanging disk are respectively connected with two ends of the horizontal lever; the transverse shaft is horizontally arranged and is perpendicular and fixedly connected with the horizontal lever; the end parts of the transverse shaft are fixedly connected with the eccentric transmission shafts through the eccentric holes; the bottom of the turbine shaft is connected with the transverse shaft in a rotatable manner; the eccentric shafts are connected with a pressurization head through rolling bearings; the bottom end of the pressurization head is in contact with the top end of a force transmission rod; the lower end of the force transmission rod is fixedly connected with a pressurization plate in the consolidation container.

Cast-in-place reinforced concrete underground structure lateral soil pressure test device and method

Abstract: A cast-in-place reinforced concrete underground structure lateral soil pressure test device comprises a soil pressure test system and an air pressure eject system. The soil pressure test system comprises a soil pressure sensor with an oil film, a test cable, a measuring meter and a sensor mounting seat; the air pressure eject system comprises a cylinder, an air pump, a pressure pipe and a cylinder flange; the soil pressure sensor is mounted on the sensor mounting seat, the cylinder is mounted on a reinforced cage framework through the cylinder flange, the piston rod of the cylinder is connected to the non-bearing face of the pressure sensor, and the port of the cylinder is connected to the air pump through a pressure pipe. The cast-in-place reinforced concrete underground structure lateral soil pressure test device is simple to mount and operate, cost is low, mounting members are purchased conveniently, mounting accuracy is high, testing result is reliable, and the device is easy to promote and apply.

Testing system simulating ultimate dynamic bearing capacity of cyclic load lower plate anchor

Abstract: The invention provides a testing system simulating the ultimate dynamic bearing capacity of a cyclic load lower plate anchor. The testing system comprises a plate anchor model, a cross-shaped supporting frame, a cyclic loading device and a measuring device, wherein the cross-shaped supporting frame is used for limiting an anchor shank of the plate anchor model to move perpendicular to the seabed surface. The cyclic loading device is used for exerting cyclic loads on the anchor shank and comprises a transmission device, a cyclic load and displacement load converting device and a displacement correcting device, the transmission device is used for converting constant-speed rotation input by a motor into sine simulating reciprocating rotation, the cyclic load and displacement load converting device is used for converting the reciprocating rotation into superposition of appointed constant loads and sine simulating loads, and the displacement correcting device is used for adjusting the length of a rope according to the displacement of the plate anchor model so that it can be avoided that the amplitude of the cyclic loads is attenuated due to the displacement accumulation of the plate anchor model in multiple periods. The amplitude of the cyclic loads can be effectively controlled, pore water pressure of a soil body around the plate anchor in the circular drawing process is obtained, the destroying process of the plate anchor and the soil body around the plate anchor is directly observed, and the ultimate dynamic bearing capacity of the cyclic load lower plate anchor is reasonably evaluated.

Soil consolidation detector of using weight and air pressure combined loading and detection method

Abstract: The invention provides a soil consolidation detector of using weight and air pressure combined loading and a detection method. The soil consolidation detector is suitable for the technical field of property detection of soil and especially suitable for remolded soil consolidation process testing and consolidation process testing of natural soil with relatively high moisture content. The soil consolidation detector comprises a reaction frame, a weight loading device, a weight and air pressure loading conversion device, a sensing measurement device, a consolidation container and an air source pressure controller; after weight loading and forming of a certain settlement amount, upper counter-force is formed through an adjusting nut and a conversion accessory; an air pressure loading device is started to push the consolidation container to ascend to gradually replace a weight load; air pressure is applied to pre-determined consolidation pressure; and the deformations of soil samples in the weight loading process and the air pressure loading process are automatically switched and observed and the soil consolidation quality is recorded and controlled through two groups of sensors on the sensing measurement device. The soil consolidation detector is relatively high in accuracy and convenient to operate; and soil which is uniform in property and high in strength and has different soil consolidation degrees can consolidated under a high load condition.

Method for detecting pile foundation post-grouting quality based on multi-point ejection type sensor measuring technique

Abstract: The invention discloses a method for detecting pile foundation post-grouting quality based on a multi-point ejection type sensor measuring technique. The method includes the steps that firstly, sensors are installed, wherein the sensors with hydraulic cylinders or pneumatic cylinders are fixed to main ribs of a steel reinforcement cage and the signal acquisition input ends of an external acquisition instrument are connected with the output ends of the sensors; and the sensors are arranged upwards along the bottom of the steel reinforcement cage; secondly, the steel reinforcement cage is fixedly installed in a pre-dug pile hole of a filling pile; thirdly, after the steel reinforcement cage is put in place, the sensors are ejected out through the hydraulic cylinders or the pneumatic cylinders, and the ejected sensors make contact with the hole wall of the filling pile; fourthly, concrete is poured into the pile hole of the filling pile; fifthly, the acquisition instrument is used for reading numerical values detected by the sensors at various depths before grouting is performed; sixthly, grouting is performed; and seventhly, after grouting is finished, the acquisition instrument is used for reading numerical values detected by the sensors at various depths after grouting is performed; and through comparison of the numerical values before and after grouting is performed, the distribution state of grout in soil beside the pile can be obtained.

Vertical well drainage consolidation soft foundation processing model test device and test method

Abstract: The invention discloses a vertical well drainage consolidation soft foundation processing model test device and test method, the vertical well drainage consolidation soft foundation processing model test device is characterized in that: a drainage vertical well is arranged in the box body of a model test box, a soft soil foundation is filled between the box body and the vertical well, a pore pressure and temperature integrated sensor is arranged in the soft soil foundation, a horizontal sand cushion layer, a steel plate and a settlement gauge are arranged on the soft soil foundation, a force transmission rod is fixedly arranged on the steel plate, the lower end of a jack is connected with the force transmission rod, the upper lower end of the jack is movably connected with a loading lever, one end of the loading lever is hinged with a counterforce frame, and the other end of the loading lever is provided with a hook; the test method is as follows: fixing a PVC pipe and a U-shaped heat conduction pipe in the model test box, filling soft clay, burring the pore pressure and temperature integrated sensor, turning a computer type water circulation heater on, heating a soil sample with hot water in the U-shaped heat conduction pipe, grading and loading, and testing temperature, pore water pressure and ground surface settlement data in the test process; and the test method has the advantages of reasonable and reliable analysis of laws of changes and developments of temperature, pore pressure and settlement of the vertical well foundation.

Hydraulic control punching box type wave generation device and method

Abstract: The invention discloses a hydraulic control punching box type wave generation device and method.The hydraulic control punching box type wave generation device comprises a testing water channel, a hydraulic jack, a punching box, a transmission rod, a cam shaft and a high-speed camera.The hydraulic jack is adjusted, and the height of a wave maker is controller, so that the maximum underwater penetration of the punching box is adjusted, and the cam shaft connected with a rotating shaft of a motor is used for controlling the working stroke of the punching box.A groove-type guide rail is arranged on the rear side of the cylindrical punching box and tightly attached to the rear wall of the testing water channel.The punching box is designed in a cylindrical shape, waves are generated by collision between the punching box and the water surface, and waves generated by the arc structure of the punching box are closer to natural waves.The function of adjusting the wave height, the wave length and the period of the waves is achieved by comprehensively controlling the maximum underwater penetration, stroke and frequency of the punching box.The motor rotates to drive the punching box to move up and down to generate waves, the characteristics of the generated waves can be directly observed through the side wall of tempered glass, and the high-speed camera is fixed to the exterior of the water channel, so that wave information is obtained in real time, and the information is transmitted to an ocean wave spectrum display.