44 results about "Falling weight deflectometer" patented technology

The invention discloses a semi-rigid base pavement damage detection and polymer grouting fast maintenance technology, which utilizes a falling weight deflectometer (FWD) and a ground penetrating radar (GPR) to detect and evaluate the performance of the pavement, identify the pavement damage and realize the lossless and fast detection of the semi-rigid base pavement damage. A grouting hole is perforated on the section that needs damage treatment and polymeric materials are injected into the hole to repair the pavement. The maintenance technology has the advantages of speedy construction, good durability, strong pertinence and excellent waterproof performance of the injected polymeric materials, which not only saves a large amount of funds and construction periods and avoids the adverse social effects caused by long affected traffic, but also is beneficial to environmental protection and resources-saving . The semi-rigid base pavement damage detection and polymer grouting fast maintenance technology of the invention integrates damage lossless detection technology such as the FWD and the GPR, etc. with the polymer grouting fast maintenance technology, thus providing a whole set of advanced, efficient, economical and practical technology for detecting and maintaining the semi-rigid base pavement damage.

The invention discloses a bridgehead vehicle bump prevention and control high polymer grouting technique and a construction method thereof. Aiming at the problems of bridgehead butt strap gapping and sinking problems, nondestructive detection systems of a ground penetrating radar (GPR), a falling weight deflectometer (FWD), a laser level and the like are comprehensively applied to detection and monitoring; and a high polymer material is injected to the bottom of a bridgehead butt strap or the bottom of a sleeper beam, the volume of the material is quickly expanded and the material is cured after chemical reaction, so that the gapped butt strap is quickly filled and raised, the roadbed is reinforced, and bridgehead vehicle bump is radically prevented and controlled. Compared with the conventional treatment method, the technique has obvious innovation on the aspects of technical principles and construction methods, has the characteristics of good durability, short construction period, strong pertinence and the like, and initiates a new advanced, efficient, economic and practical bridgehead bump prevention and control path.

The invention discloses a cement concrete pavement detachment identification and polymer grouting fast maintenance technology, which utilizes a falling weight deflectometer (FWD) and a ground penetrating radar (GPR) to detect and evaluate the performance of the pavement, identify the detachment situation of pavement slabs and realize the lossless and fast identification of the cement concrete pavement detachment. A grouting hole is perforated on the pavement slabs that need detachment treatment and polymeric materials are injected into the hole to repair the pavement. The maintenance technology has the advantages of speedy construction, good durability, strong pertinence and excellent waterproof performance of the injected polymeric materials, which not only saves a large amount of funds and construction periods and avoids the adverse social effects caused by long affected traffic, but also is beneficial to environmental protection and resources-saving. The cement concrete pavement detachment identification and polymer grouting fast maintenance technology of the invention integrates detachment identification lossless detection technology such as the FWD and the GPR, etc. with the polymer grouting fast maintenance technology, thus providing a whole set of advanced, efficient, economical and practical technology for detecting and maintaining the cement concrete pavement detachment.

The invention discloses a subgrade defect identification and polymer grouting fast strengthening technology, which utilizes a falling weight deflectometer (FWD) and a ground penetrating radar (GPR) to detect and evaluate the performance of the subgrade, identify the defect of the subgrade and the position of the defect, and realize a lossless and fast identification of the subgrade defect. A grouting hole is perforated on the section that needs defects treatment and polymeric materials are injected into the hole to repair the subgrade. The maintenance technology has the advantages of speedy construction, good durability, strong pertinence and excellent waterproof performance of the injected polymeric materials, which not only saves a large amount of funds and construction periods and avoids the adverse social affect caused by long affected traffic, but also is beneficial to environmental protection and resource-saving. The subgrade defect identification and polymer grouting fast strengthening technology of the invention integrates the FWD and the GPR subgrade defect lossless identification technology with the polymer grouting fast maintenance technology, thus providing a whole set of advanced, efficient, economical and practical technology for identifying, strengthening and maintaining the subgrade defect.

The invention discloses a method for quickly repairing a cavity disease of a cement concrete pavement, which aims to achieve low cost, quick repairing speed and good effect. The method provided by the invention comprises the following steps: judging the cavity position at a plate angle position and a plate block center position of a cement concrete pavement by using a falling weight deflectometer and a ground penetrating radar; arranging injected holes on the plate block of the cement concrete pavement, wherein the injected slurry adopts a cement coal ash composite material; absorbing injected slurry from a stirring machine by using an injecting pump; then injecting the slurry to the cavity position of the cement concrete pavement after being pumped by a high pressure rubber pipe; after finishing the injection, maintaining the cement concrete pavement for 4-6 hours; blocking the injected hole by using mortar; and after statically placing for 8-12 hours, polishing the part higher than the pavement until the part higher than the pavement is kept flat as the original pavement.

The invention discloses a road quality detection method and system based on a FWD (Falling Weight Deflectometer) and a 3D ground penetrating radar. The system comprises the FWD, the ground penetrating radar and a data processing device. The method comprises the following steps: finding deflection data greater than a threshold from acquired deflection data; performing analytical processing on the acquired ground penetrating radar image so as to find road diseases in the ground penetrating radar image; and performing consistency judgment on sites corresponding to the found deflection data and the road diseases. According to the method and system disclosed by the invention, the road diseases can be timely found, the road is accurately cured and maintained, the method and system have significances for preventing the road from being early damaged, delaying overhauling and prolonging the service life of the road, and an important basis and a technical support can be provided for old road reconstruction and maintenance and overhauling. The road quality detection method and system based on the FWD and the 3D ground penetrating radar disclosed by the invention can be widely applied to the field of road engineering.

The invention discloses high polymer grouting technology for treating a tunnel void and a construction method thereof. The technology comprises the following steps of: detecting the tunnel void on the basis of a ground penetrating radar (GPR) or a falling weight deflectometer (FWD); and injecting a high polymer material to a void part according to the condition of the tunnel void, wherein after the material reacts, the volume is expanded quickly and the material is cured to quickly fill the void. The technology has the characteristics of good treatment effect, quick construction, no requirement on curing, obvious target, high controllability, cost conservation and the like. Compared with the traditional tunnel void treating method, the technology is innovative obviously in the aspects of technical principle and construction method and develops a new, quick, economical and practical way for maintaining a tunnel and enabling the tunnel to be durable.

The invention provides a method for rapid treatment of damage of a cavity beneath a cement concrete pavement slab and has the advantages of low cost, a fast repairing speed and a good effect. According to the invention, a falling weight deflectometer and a ground penetrating radar are used for determination of a cavity position at corners and a center position of a cement concrete pavement slab; then grouting holes are arranged in the cement concrete pavement slab, wherein an emulsified asphalt cement-based composite material is used as a grouting slurry; a grouting pump is employed to pump the grouting slurry from a mixer, and the grouting slurry is injected into the cavity position of the cement concrete pavement after pumping pressing by a high-pressure rubber hose; after grouting is finished, the cement concrete pavement is maintained for 4 to 6 h; and mortar is used to plug the grouting holes, after the grouting holes are stood for 8 to 12 h, and then parts of the pavement higher than the pavement is polished until the parts of the pavement are as high as the original pavement.

The invention discloses a structural maintenance and design method of a semi-rigid base-layer asphalt pavement. The structural maintenance and design method is characterized by comprising the following steps: rating pavement cracking conditions according to a pavement condition index PCI, and sampling asphalt pavements with intermediate or serious cracking conditions by virtue of cooperation of a falling weight deflectometer FWD and a pavement drilling core, so as to acquire design parameters of each structural layer, wherein the design parameters include the thickness and the modulus of each structural layer of a primary pavement; detecting the fatigue property of an asphalt mixture of an overlay, wherein the fatigue property can be estimated by measuring volume parameters and substituting the volume parameters into an empirical formula and can be actually measured by virtue of an indoor fatigue test; establishing a 3D pavement overlay structure finite element model, counting maximum equivalent strain epsilonVM at the bottom of an asphalt overlay layer at a crevice position, substituting epsilonVM into a fatigue equation, and correcting a pavement fatigue life by virtue of an environmental correction coefficient, so as to finally obtain the thickness of the asphalt overlay layer.

The invention relates to the technical field of non-destruction detection of highway subgrade and pavement strength, and in particular discloses a multipoint sensor FWD (Falling Weight Deflectometer). A hasp is fixedly arranged at the lower end of a bearing device of the multipoint sensor FWD and can be in lap-joint with a sensor cross beam, a hasp wielding combination is arranged at the right end of the sensor cross beam, the other end of the sensor cross beam is fixedly connected with the upper end of the bearing device through a steel wire rope after passing through three pulleys arranged on a trailer chassis, and deflection sensors, a guiding mechanism and a balance weight are arranged on the sensor cross beam,. According to the multipoint sensor FWD disclosed by the invention, a lifting mechanism of each cross beam of the multipoint sensor FWD is simplified, and a mounting box of each multipoint sensor cross beam is convenient to dismantle, thus the maintenance is improved; in addition, the guiding mechanism is additionally arranged on the sensor cross beam, thus the influence of a lateral force on the multipoint sensor cross beam is automatically regulated and eliminated, the structure stability is increased, and the deflection measurement precision is improved.

The invention discloses a novel road foundation repair method, which is high in repair speed and high in safety performance, and can prolong the service life of a repaired road and save the maintenance costs. The method is characterized by comprising the following steps: (1) detecting a pavement base layer by a falling weight deflectometer (FWD) or a ground penetrating radar (GPR) to determine that a pavement suffers from a shallow pavement disease or a deep pavement disease according to pavement bearing capacity data displayed by falling weight deflection and the detection result of an inversion image of the GPR, and executing the step (2) to deal with the shallow pavement disease, executing the step (3) to deal with the deep pavement disease, or repairing the shallow part and the deep part of the pavement sequentially to deal with the shallow pavement disease and the deep pavement disease; (2) repairing to deal with the shallow pavement disease; and (3) repairing to deal with the deep pavement disease.

The invention discloses a highway airplane runway surface use performance testing method based on uninterrupted traffic. A to-be-tested section is closed, and vehicles are guided to drive in a decelerated way. A laser roughness measuring instrument is used to measure the roughness of the section. A friction coefficient testing vehicle is used to measure the friction coefficient of the section. A falling weight deflectometer is used to measure the deflection of the section. A three-meter ruler is used measure the roughness of the section. A pendulum friction meter is used to measure the friction coefficient. A pavement structure depth testing instrument is used to measure the structure depth of the pavement. A bearing plate is used to measure the deflection curve of the pavement. A drilled core sampling device is used to measure the thickness of the pavement, and is used to carry out related indoor tests. Appearance inspection is carried out manually, and a pavement damage condition is inspected. The highway airplane runway surface use performance testing method is advantageous in that two lanes of an upstream line and a downstream line are closed, and safety measures are taken, and the driving speeds of the vehicles are limited, and a decelerated passing way is adopted, and therefore space is provided for the highway runway on-site testing, and the traffic is not affected substantially.

The invention discloses a method for evaluating a road technical condition based on a non-destructive testing technique. The method includes performing road surface image collection by utilizing an intelligent road surface damage automatic collection system; performing data collection on the inside of the pavement structure by utilizing 3D ground penetrating radar; subjecting the images collectedby the intelligent road surface damage automatic collection system to manual or intelligent analysis; processing data, collected by the 3D ground penetrating radar, of the inside of the pavement structure; comparing the data collected by the intelligent road surface damage automatic collection system with the image data collected by the 3D ground penetrating radar; detecting positions, abnormal inimages collected by the 3D ground penetrating radar, by a falling weight deflectometer again; estimating whether the pavement structure is damaged or not according to a pavement structure modulus andcarrying capacity; performing comparison with the images collected by the 3D ground penetrating radar to determine the specific location of damage inside the pavement structure; and sampling and drilling a core sample to verify accuracy of a detection result, and giving a scientific evaluation of the road technical condition and a reasonable maintenance plan.

The invention provides a trailer type electric falling weight deflectometer. The trailer type electric falling weight deflectometer comprises a trailer, a deflectometer arranged on the trailer and anupper computer for controlling the deflectometer, wherein the deflectometer comprises an outer frame body, a loading device arranged in the outer frame body, a bearing device arranged below the loading device and a measuring device connected to the side surface of the bearing device; the loading device comprises an electromagnet, and a drop hammer connected below the electromagnet; the bearing device comprises a transition plate arranged below the drop hammer; a pressure sensor is arranged below the transition plate; a bearing frame is connected below the pressure sensor; a bearing plate is arranged at the bottom of the bearing frame; and a displacement sensor is arranged on the bearing plate. According to the trailer type electric falling weight deflectometer, through the adoption of theelectromagnet structure, the defects that an existing hydraulic deflectometer is prone to oil leakage and oil penetration and has high working noise are solved.

The invention relates to a method for evaluating roadbed grouting reinforcement effects. The method is characterized by comprising steps of (1), arranging measuring points; (2), testing pre-grouting roadbed dynamic elasticity moduli, in other words, testing the various detection positions and acquiring the pre-grouting roadbed dynamic elasticity moduli of the various detection positions by means of computation; (3), testing and acquiring post-grouting roadbed dynamic elasticity moduli; (4), evaluating the grouting reinforcement effects. Representative values E<0> of the roadbed dynamic elasticity moduli of the various measuring points in evaluation units are computed according to formulas, and representative values E<0><pre-grouting> of the pre-grouting roadbed dynamic elasticity moduli and representative value E<0><post-grouting> of the post-grouting roadbed dynamic elasticity moduli are computed, so that increase rates E<0><increase rate> of the roadbed dynamic elasticity moduli can be acquired by means of computation. The method has the advantages that the roadbed dynamic elasticity moduli can be quickly measured on the basis of a falling-weight deflectometer process and are feature parameters which reflect the soil strength of roadbeds, the method is nondestructive, speedy, simple and effective, and accordingly huge engineering loss due to roadbed grouting construction quality defects can be prevented.

The invention discloses a method for detecting and evaluating the compaction uniformity of an inorganic stabilized granular base course of a road. According to a detection point arrangement principle, the Evdi of a to-be-estimated section of the road is detected by adopting a PFWD (Portable Falling Weight Deflectometer); a detection result is subjected to statistic analysis, so as to obtain a deformation modulus average value and a variance; upper and lower confidence limits are calculated; the three-dimensional curved surface of Evd is cut; value lines of the Evd and the like are projected out; the area Sh of a qualified region and the area Sq of an overall region are calculated; a uniformity index t is calculated according to a definition; the compaction uniformity is estimated according to an evaluation standard; a judgment method of a compacted weak region of a roadbed is to define the compacted weak region of the roadbed by adopting an Evd lower confidence region of the to-be-detected section of the road; the quick aftercompaction can be carried out according to the position of the weak region.

The present invention relates to a method for detection of a bridge hinge joint condition through a FWD (Falling Weight Deflectometer). The method comprises the following steps: detecting each hinge joint on a cross section in a span; selecting the next section at an interval of L in the vertical direction toward the direction of the bridge head; detecting the horizontal hinge joint capability of each hinge joint in the direction perpendicular to each hinge joint through adoption of the FWD; evaluating the hinge joint condition according to the grading standard of the hinge joint load transfer capability. According to the invention a FWD is used for detection and evaluation of hinge joint capabilities of hinge joints in the maintenance detection of a built bridge, and is able to quickly, accurately and effectively measure the hinge joint capabilities of hinge joints of a bridge, therefore the influence on the traffic is small and the accuracy is high.

The invention relates to the field of an FWD (falling weight deflectometer), and particularly provides a system and a method for metering impact load of the FWD. The system for metering the impact load of the FWD comprises a substrate, a bearing plate, pressure sensors, a data collecting device and a data processing device, wherein the bearing plate is stacked right above the substrate; the multiple pressure sensors are uniformly distributed between the upper surface of the substrate and the lower surface of the bearing plate; the data collecting device is connected with the pressure sensors;the data processing device is connected with the data collecting device through a data transmission line. The device for metering the impact load of the FWD is low in manufacture cost, simple in structure and capable of being recycled, moved randomly and moved to the scene for use, accuracy of values measured by the pressure sensors is guaranteed, and accordingly, the FWD can be accurately calibrated.

The invention discloses a method for nondestructively detecting asphalt pavement crack conditions. The method includes steps of 1, measuring difference delta L1 of deflection values of first measuredpoints and second measured points by the aid of falling weight deflectometers; 2, shifting corresponding load application points to the other side of each crack and measuring difference delta L2 of deflection values of third measured points and fourth measured points by the aid of the falling weight deflectometers; 3, judging the asphalt pavement crack conditions according to an equation of deltaL=delta L2-delta L1. The distance from each load application point to the corresponding crack is a preset distance constant value, each load application point, the corresponding first measured point and the corresponding second measured point are positioned on the same side of the corresponding crack, and the distance from each load application point to the corresponding crack, the distance from the corresponding first measured point to the corresponding crack and the distance from the corresponding second measured point to the corresponding crack are sequentially enlarged. The locations of the third measured points/the fourth measured points relative to the load application points are identical to the locations of the first measured points/the second measured points at the step 1 relativeto the load application points, and the cracks are positioned on the center lines between the third measured points and the fourth measured points. The method has the advantages that the asphalt pavement crack conditions can be nondestructively detected by the aid of the method so as to be accurately evaluated; the method is easy and convenient to operate and extremely low in implementation cost.

The invention discloses a multifunctional detection vehicle. The multifunctional detection vehicle comprises a vehicle body and a three-dimensional scanner mounted at the rear end of the vehicle body,wherein a mounting hole penetrating through a chassis of the vehicle body is arranged in the vehicle body, and a drop hammer deflectometer is arranged on the mounting hole; the drop hammer deflectometer comprises a door frame-shaped support and a drop hammer device; two lifting hydraulic cylinders are arranged on the door frame-shaped support; a bearing plate and two connecting arms fixed on thebearing plate are arranged on the drop hammer device; and piston rods of the two lifting hydraulic cylinders are respectively connected with the two connecting arms. According to the multifunctional detection vehicle, the drop hammer deflectometer and the three-dimensional scanner are integrated into the detection vehicle together, and a unique control system is matched, so that the road surface condition is detected in the running process of a vehicle at the speed of one hundred kilometers.

The invention discloses a heavy falling weight deflectometer bearing disc self-adapting pavement device, and relates to the technical field of a falling weight deflectometer. The heavy falling weightdeflectometer bearing disc self-adapting pavement device concretely comprises a bearing main body, frame carrying mechanisms, a falling weight mechanism, a self regulation mechanism and a base, wherein the frame carrying mechanisms are arranged at two sides of the inner side of the bearing main body; the falling weight mechanism is arranged under the frame carrying mechanisms; the self regulationmechanism is arranged at the middle lower part of the bearing main body; the base is arranged under the self regulation mechanism; the bearing main body consists of an upper lifting disc and a lower lifting disc; the falling weight mechanism comprises first heavy hammers and second heavy hammers; the first heavy hammers are respectively arranged at the right corner of the front side of the upper part and the left corner of the back side of the upper part of the base. The heavy falling weight deflectometer bearing disc self-adapting pavement device has the advantages that through the arrangement of the self regulation mechanism, the device can be automatically regulated; according to the pavement gradient, the impact direction on the pavement always maintains the vertical direction, and isnot in a vertical state with the pavement.

A falling weight deflectometer (1). The falling weight deflectometer comprises a load plate (2) adapted to engage a test surface, a force transmission means (5) adapted to transmit a force to the load plate (2), a buffer means (19), and a weight (8, 9, 10) adapted to impact said force transmission means (5) via said buffer means (19) so as to provide a force to be transmitted to said load plate (2) via said force transmission means, a guide means (14, 20) for guiding said weight (8, 9,10) towards said force transmission means, and a lifting means for lifting said weight to a predetermined height above said force transmission means. The lifting means comprises an electric (15) motor driving a threaded spindle in 17 engagement with the weight (8, 9, 10).