271 results about "Pressure grouting" patented technology

The invention relates to the technical field of fracturing engineering safety monitoring and intelligent early warning, in particular to a fracturing construction monitoring and early warning system and method, and the method comprises the steps: obtaining initial equivalent system resistance and a flow state correction index; constructing a reference physical model; calculating a theoretical pressure value; calculating a deviation index; when the deviation index is larger than a preset dynamic judgment threshold value, geological state inversion is triggered; if the deviation index is smaller than or equal to the dynamic judgment threshold value, returning to the step of collecting the current real-time pressure value and the current real-time displacement value of the high-pressure grouting pump in real time; carrying out reverse solving to obtain updated equivalent system resistance; calculating to obtain a risk index; generating a grading early warning and decision instruction; in response to early warning event confirmation, the initialized equivalent system resistance in the reference physical model is updated to the updated equivalent system resistance; according to the invention, automation and intelligence of early warning and decision making are realized, the construction safety is ensured, and the engineering quality is improved.

The invention particularly discloses a layered and segmented composite fabricated foundation pit support structure and a construction method. According to the overall technical scheme, double enclosure of deep mixing piles and a cemented soil retaining wall is followed, truss rib laminated slabs are spliced in a layered and segmented mode, an anchor rod group transversely penetrates through the deep mixing piles to be anchored into the cemented soil retaining wall, anchor rod holes are also used as high-pressure grouting holes, anchor rod sleeves guide anchor rods to enter soil and assist the truss rib laminated slabs to be in place, and high-strength grouting materials are grouted at high pressure; according to the design concept of the pile-wall-plate-anchor rod composite type foundation pit support structure, a technical system that a soil layer outside a foundation pit is stabilized through a cement soil retaining wall, force is borne by deep mixing piles, support grouting forming is conducted through a truss rib laminated plate, and overall cooperative bearing is strengthened through anchor rod driving is constructed. And the supporting requirements of complex geological environments and large-depth foundation pits are stably met.

The invention discloses a ground surface settlement prevention and control method based on mold bag grouting. The ground surface settlement prevention and control method comprises the following steps that geological investigation is conducted, and pile positions are arranged; drilling at the pile position to form a pile hole; the method further comprises the following steps that the main grouting pipe and the geotextile bag on the main grouting pipe are placed into the pile hole together, and backfilling is conducted between the pile hole and the main grouting pipe; pressure grouting is conducted in the main grouting pipe, the grout in the main grouting pipe rises gradually, meanwhile, the grout in the main grouting pipe is pressed into the geotextile mold bag through the secondary grouting pipe, and the geotextile mold bag expands gradually in the radial direction and extrudes the surrounding soil body; and grouting is stopped, and after the grout in the main grouting pipe and the soil engineering mold bag is hardened, the main grouting pipe and the soil engineering mold bag jointly form a mold bag pile body. The construction method has the beneficial effects that the grouting pipes are arranged underground, the expandable mold bags are installed at the preset positions of the grouting pipes, after grout is injected, the mold bags expand directionally and evenly extrude the surrounding soil body, and therefore active compaction of the soil body is achieved, and the rigidity and integrity of a foundation are remarkably improved.

The invention particularly discloses a layered and segmented composite fabricated foundation pit support structure and a construction method. According to the overall technical scheme, double enclosure of deep mixing piles and a cemented soil retaining wall is followed, truss rib laminated slabs are spliced in a layered and segmented mode, an anchor rod group transversely penetrates through the deep mixing piles to be anchored into the cemented soil retaining wall, anchor rod holes are also used as high-pressure grouting holes, anchor rod sleeves guide anchor rods to enter soil and assist the truss rib laminated slabs to be in place, and high-strength grouting materials are grouted at high pressure; according to the design concept of the pile-wall-plate-anchor rod composite type foundation pit support structure, a technical system that a soil layer outside a foundation pit is stabilized through a cement soil retaining wall, force is borne by deep mixing piles, support grouting forming is conducted through a truss rib laminated plate, and overall cooperative bearing is strengthened through anchor rod driving is constructed. And the supporting requirements of complex geological environments and large-depth foundation pits are stably met.

The invention discloses a device and method for preventing soft coal seam gas extraction drill hole deformation and hole collapse, and relates to the technical field of coal seam gas extraction, the device comprises an anti-collapse mechanism used for ensuring the accuracy and controllability of the reinforcing range and effectively preventing invalid slurry loss, and the anti-collapse mechanism comprises a hole protection sleeve unit, a connecting unit and a bag unit; the bag unit is arranged on the outer side of the connecting unit and comprises a stacked bag installed on the outer side of the stacked casing pipe through the connecting unit, a bottom bag is installed on the outer side of the bottom casing pipe through the connecting unit, and high-strength grout is injected into the bag unit through a high-pressure grouting pump, so that the stacked bag and the bottom bag expand in a drill hole to fill surrounding cracks; and the invalid diffusion path of the slurry is blocked, targeted reinforcement of the soft coal seam is achieved, the problem that the slurry is lost along the maximum crack channel in traditional grouting is solved, the stability of the gas extraction drill hole is remarkably improved, and the service life of the gas extraction drill hole is remarkably prolonged.

The invention provides a grouting-curing-intercepting cross-cut rapid coal uncovering method, and relates to the technical field of cross-cut coal uncovering. The method comprises the steps that drilling topological mapping is conducted on a target area, a connected gas interception and extraction network is constructed, and gas attenuation characteristics are extracted to determine a grouting permeation resistance coefficient; then, a high-pressure grouting dynamic pressurization gradient sequence is formulated, and an in-situ test execution unit is configured in a negative pressure guide reserved area; establishing a process response state diagram containing bag strength, sieve tube smoothness and crack filling test nodes, generating an optimal grouting path by adopting closed-loop feedback logic, and collecting a multiphase flow grouting response data set; and finally, generating a complete solidification curtain map by using the data set, executing a solidification-gas interception collaborative verification decision, and outputting a safe coal uncovering instruction. By means of digital closed-loop control, accurate solidification of superfine cement on coal seam microcracks and efficient interception and extraction of gas are achieved, and the safety and operation efficiency of cross-cut coal uncovering are remarkably improved.

The invention relates to the technical field of settlement post-cast strips, in particular to a pre-closed advanced water stop grouting device and method.The pre-closed advanced water stop grouting device comprises a basement top plate, a bottom plate, a cover plate and a grouting sleeve and further comprises a self-adaptive adjusting assembly; the self-adaptive adjusting assembly comprises an inner cylinder, an outer cylinder, a spring, a sealing ring and a pre-tightening force adjusting component, and when the building body settles, the cover plate descends to drive the outer cylinder to descend, and then the spring is extruded; the springs on the two sides generate reverse buffering force after being compressed, the force is transmitted to the cover plate through the outer cylinder, the internal stress of the cover plate caused by differential settlement is effectively counteracted, and it is avoided that a sealing structure at the joint of the cover plate and a basement top plate cracks due to rigid pulling; and after the settlement is stable, pressure grouting is performed through the grouting sleeve, so that the problems of cracking of the cover plate and failure of sealing structures such as a sealant and a waterproof coiled material due to rigid pulling are solved.

This invention provides a directional filling device for seepage channels in dikes, comprising a main mounting frame, a fixed connecting seat fixedly mounted at the bottom of the main mounting frame, a central connecting rod fixedly mounted at the lower end of the fixed connecting seat, and a detection drive seat fixedly mounted at the lower end of the central connecting rod. The detection drive seat has an outward-opening detection installation cavity at its bottom, and a movable detector lifting seat is located within the detection installation cavity. This invention integrates a geological detection sensor and a lifting drive mechanism to achieve simultaneous exploration and filling, accurately identifying the geometric parameters of the seepage channel and directional filling along the channel's centerline, avoiding blind grouting and material waste. This invention employs a bag-type sealing mechanism to first isolate the section to be filled into a closed cavity before low-pressure grouting, eliminating the need to rely on material expansion force to split the soil and avoiding secondary disturbance to the dike body. It is particularly suitable for the reinforcement of dikes with defects.

The application relates to a post-poured concrete construction method for a column of an underground vertical structure by a reverse construction method, and particularly relates to the following steps: constructing a column head, installing longitudinal steel bars of a column body and a high-pressure grouting pipe; installing other structural steel bars; setting a mortar reverse ridge; installing a column body formwork and a supporting system, setting a vibrating hole and an exhaust hole; installing a concrete discharging pipe, setting a vibrating hole for vibration; after the vibrating hole at the top of the column body is closed, mainly performing concrete vibration through a concrete pouring opening of the last layer and the vibrating hole; performing non-pressure water test on the grouting pipe; curing the concrete, removing the formwork; performing ultrasonic detection on a construction joint interface position; performing high-pressure grouting; performing ultrasonic detection on the construction joint interface again; constructing the column body; closing a floor hole opening by the reverse construction method, and removing temporary supports one by one. The application has the advantages that the concrete is fully vibrated, the vibration efficiency is high, gas in the construction joint position is fully discharged, two construction joints are not generated, the construction cost is low, and the filling material at the construction joint position is safe and reliable.

The present application belongs to the technical field of high-pressure grouting process optimization, and particularly relates to a high-pressure grouting process optimization method for roadway water inrush cracks. The method first improves the Retinex and dark channel priori combination for image preprocessing; based on the attention-enhanced U-Net, the crack is accurately segmented, and the length, width and depth are quantified; the distributed water pressure sensor is arranged in the crack influence area, the Gaussian smoothing, sliding window linear fitting and correlation analysis are used to remove the abnormal measuring points and calculate the weighted average water pressure; taking the crack geometry and effective average water pressure as the input, a double-branch prediction model is constructed to output the preliminary range of slurry-water ratio, grouting pressure and segmented grouting length; further, a neural network prediction model is constructed from the similar working conditions selected from historical samples, and the improved particle swarm optimization is combined to repair the longitudinal wave velocity of the post-rock mass close to the normal value as the target, and the three types of process parameters are optimized to obtain the optimal grouting scheme.

A boulder pile foundation construction method comprises the following steps that boulder detection is conducted, specifically, a detection hole is drilled in a preset pile foundation point position, and whether boulders exist or not is judged; and if the boulders are detected, auxiliary detection holes are formed in the peripheral side of the preset pile foundation point position to detect boulder boundaries. Selecting a pile foundation type: if no boulder exists at a preset pile foundation point position, constructing a rotary excavating pile; if the boulder exists at the preset pile foundation point position and the auxiliary detection hole is still the boulder stratum, it is judged that the boulder can be penetrated, and separate pile construction is conducted; and if no boulder exists in the auxiliary detection hole, the preset pile foundation point position is moved, and the rotary excavating pile is constructed after the boulder is avoided. Sub-piles distributed in a radial shape are constructed at preset pile foundation points capable of penetrating through the boulder, and it is ensured that the sub-piles penetrate through different areas of the boulder through positioning; and the anchor rod is lowered after drilling, and the anchor rod is anchored with boulders and stratums through pressure grouting. Mounting and primary pouring of a steel sleeve: after pile-dividing grouting and primary setting, treating the top of the anchor rod, sleeving the steel sleeve outside the anchor rod, and pouring concrete into the steel sleeve after the steel sleeve is fixed. And the bearing platform is constructed and used for supporting the photovoltaic flexible support. According to the construction method, convenient and low-cost pile foundation construction of the boulder stratum can be achieved, and the pile foundation supporting performance is good.

The invention relates to the technical field of foundation engineering, in particular to a sunken post-tensioning anti-floating anchor rod fabricated anchoring joint construction method which comprises the following steps: carrying out an anchor rod uplift bearing capacity test; constructing a cushion layer and manufacturing an anchor rod, wherein the anchor rod comprises a steel strand; an anchor rod construction point is positioned on the cushion layer; drilling and cleaning an anchor hole; lowering the anchor rod; performing primary normal-pressure grouting and secondary high-pressure grouting; maintaining the anchor rod; constructing a waterproof layer; binding reinforcing steel bars and installing a sealing anchor base; pouring structural bottom plate concrete; tensioning and locking the anchor rod; according to the construction method, it can be guaranteed that the site of the structural bottom plate is flat, operation of constructors and transportation of mechanical equipment are facilitated, the effect of protecting anchoring joints of the anchor rods is achieved, and the damage risk of the anchoring joints is reduced; compared with a traditional convex type or concave type anchoring node, the bottom plate can be reduced by a certain thickness, waterproof construction operation is simpler and more convenient, the labor material cost can be greatly reduced, the construction difficulty can be lowered, the self weight of the bottom plate is reduced, and the effect of shortening the construction period is achieved.

The invention discloses a deep foundation pit anchor cable supporting device based on single-face formwork erecting and a construction method. The construction method comprises the following preparation steps that firstly, early-stage construction preparation and supporting cast-in-place pile construction are conducted, and site leveling, surveying and setting-out and construction equipment debugging are completed according to a deep foundation pit engineering design file; and the supporting cast-in-place pile is constructed at the preset position of the foundation pit design side boundary through the cast-in-situ bored The embedded steel bar construction core link is optimized, high-strength ribbed steel bars are selected to be matched with special epoxy embedded steel bar glue, through standard hole cleaning, pressure grouting and sufficient maintenance, it is ensured that embedded steel bars and supporting cast-in-place piles are tightly bonded and stably stressed, a waist beam and a soil retaining plate are integrally designed, the steel bars are integrally bound and formed, and formworks share a supporting system; the stress concentration at the connecting position is structurally avoided, tight lap joint of the upper-section soil retaining plate and the lower-section soil retaining plate is achieved through a tongue-and-groove structure, and the double-waterproof design of the water swelling strip and the polyurethane sealant is matched with the upper-section soil retaining plate and the lower-section soil retaining plate.

The invention belongs to the technical field of constructional engineering, and particularly relates to a rapid hole-forming construction process for a post-planted anti-floating anchor rod with a pressure grouting function, which comprises the links of intelligent positioning and geological adaptation preparation, self-adaptive hole-forming operation, anchor rod manufacturing and grouting, and temperature and humidity self-adaptive maintenance and acceptance. In the step of intelligent positioning and geological adaptation preparation, hole positions are positioned through three-dimensional laser scanning, conflicts are detected, a geological risk thermodynamic diagram is described by combining coring and radar scanning, and in the step of self-adaptive hole forming operation, torque and rotating speed are automatically adjusted according to the stratum, hole wall risks are monitored through sound waves, graded intermittent hole expanding is conducted, and cracks are blocked in a targeted mode. The method comprises the steps of anchor rod manufacturing and grouting, spiral rib anchor rod matching with a degradable support, double-cavity grouting pipe precise pressure control grouting, gradient grout supplementing after initial setting and temperature and humidity self-adaptive maintenance, temperature and humidity are monitored through a sensor, heat preservation and moisture preservation are automatically started, maintenance is finished after the standard is reached, and finally acceptance check is conducted to ensure that the anti-floating effect reaches the standard.

The present application belongs to the technical field of disposable plugging stopper, and specifically provides a combined pin plugging stopper and a slurry sealing and blocking method. The combined pin plugging stopper comprises a stopper pipe, a first pin, a sliding structure, a deformation piece, an inner support, a steel ball, a second pin, a connector, a slurry overflow port and a slurry outlet pipe. The stopper pipe is fixedly connected with a grouting pipe through the first pin. The other end of the stopper pipe is arranged along the central axis of the grouting pipe and is connected with the slurry outlet pipe. The steel ball is arranged inside the side of the stopper pipe close to the slurry outlet pipe. The second pin is arranged between the steel ball and the slurry outlet pipe. The sliding structure is sleeved on the stopper pipe and is provided with a plurality of deformation pieces. The end of the sliding structure close to the slurry outlet pipe is connected with the slurry overflow port arranged on the slurry outlet pipe through the connector. The inner support is arranged on the stopper pipe and between the adjacent two deformation pieces. The present application can solve the problem of sealing failure or difficult recovery in the high-pressure grouting process caused by the structural and technological defects of the existing plugging stopper.

By adding infiltration injection to the conventional high-pressure grouting method, it becomes possible to form large-diameter solidified bodies using suspended grout. Furthermore, it is possible to add injection material to excavated soil and reinject it, enabling ground improvement that is environmentally friendly and reduces CO2 emissions, while also providing a ground improvement method and injection device that can form larger solidified bodies that are lighter than conventional methods. [Solution] An injection device used in a high-pressure jet mixing method, comprising a guide pipe inserted into the ground, an injection inner pipe placed inside the guide pipe and used for injecting the injection material, and an opening / closing mechanism for opening or closing the space between the guide pipe and the injection inner pipe.

The present application relates to a kind of for locking steel pipe pile cofferdam water stop pressure grouting device, including a support frame, pressure grouting pipe, annular air bag and inflation pipe;The support frame includes upper support plate and lower support plate, there is a certain interval between upper support plate and lower support plate and welding connecting rod, multiple buckles are arranged in equidistance rotation on the edge of upper support plate, and the lower end of buckle is located below upper support plate and is inclined to the outside of upper support plate upwards;Pressure grouting pipe vertically penetrates upper support plate and lower support plate;Annular air bag is located between the upper support plate and lower support plate of support frame, annular air bag can extrude the lower end of buckle to rotate to the outside of upper support plate in inflation state, and its annular outside surface protrudes to the outside of upper support plate and lower support plate;Inflation pipe penetrates upper support plate and inflates and deflates air bag.The present application can be combined with rock by the way of high-pressure grouting to press cement slurry from inside steel pipe pile to outside steel pipe pile, so that steel pipe pile is closely combined with rock, and the water stop effect of steel pipe pile cofferdam is improved.

The invention belongs to the technical field of constructional engineering grouting, and particularly relates to a negative pressure grouting system for crack plugging and a construction method.The negative pressure grouting system comprises a perforation grout blocking structure, a crack sealing structure and a negative pressure grouting structure, and the perforation grout blocking structure comprises perforation drilling grout blocking holes in the two ends of a crack to be treated; the crack sealing structure comprises a V-shaped groove or a U-shaped groove which is formed along the crack, a sealing layer is embedded in the V-shaped groove or the U-shaped groove, the sealing layer is flush with the surface of concrete, and the negative pressure grouting structure comprises a slurry inlet hole and a negative pressure hole which are formed in the two ends of a to-be-processed section of the crack respectively. The slurry inlet hole is connected with slurry inlet equipment through a first orifice valve, the negative pressure hole is connected with vacuum generation equipment through a second orifice valve, the first orifice valve, the second orifice valve, the slurry inlet equipment and the vacuum generation equipment are connected with a control system, and the control system performs unified operation according to a control logic system.

The invention discloses a construction method for treating underground engineering leakage. The construction method comprises the following steps that 1, field investigation and leakage diagnosis are conducted; step 2, drilling and pressure relief; 3, a grouting pipe with adjustable and controllable pressure and flow is installed; step 4, preparing a cement-underwater non-dispersible mixed solution; step 5, pressure grouting; and step 8, post-processing and checking. According to the method, the treatment thought that active pressure relief is conducted firstly, and then directional grouting is conducted is adopted, after drilling pressure relief is conducted on an underground structure bottom plate or a structure side wall, accumulated water pressure is released, a low-pressure or non-pressure environment is created, special grout with underwater dispersion resistance and high fluidity is poured, plugging is conducted from the weakest position of the structure, and long-acting water stopping is achieved.

The invention provides a long-distance high-pressure grouting advanced modification method for a coal mine working face, which belongs to the field of coal mining and comprises the following steps of: drilling a plurality of first grouting holes at intervals along the tunneling direction of a roadway by taking a top plate as a reference; the roadway is tunneled after the first grouting hole is sealed and grouted; a drilling site is formed in the roadway, and a plurality of second grouting holes are drilled through the drilling site; and the second grouting holes are sealed and grouted. The coal mine reinforcing method aims at solving the problem that in the prior art, a coal mine reinforcing mode is difficult to comprehensively reinforce faults, wrinkles, collapse columns, areas with low coal and rock mass strength and peripheral key stress rock stratums. The grouting pre-reinforcement method has the advantages that grouting pre-reinforcement is carried out aiming at faults, folds, collapse columns, roadway tunneling, working face stoping and the like which are affected by low strength of coal and rock masses, the reinforcement effect is improved, the roadway tunneling efficiency is improved, and safe stoping of the working face is guaranteed.

This invention discloses a reinforcement structure and construction method for reconstructing load-bearing components using prestressed porous slab openings. The method includes site survey and structural assessment; reinforcement design calculations; construction preparation and opening pretreatment; prefabrication of steel trusses and installation of grouting pipes; installation and positioning of steel trusses; installation of grouting sealing templates; grout preparation and pressure grouting; monitoring and pressure holding during grouting; curing and template removal; repair of openings on the slab surface; treatment of the slab bottom and bonding of carbon fiber cloth; and quality inspection and acceptance. This invention provides a safe, efficient, economical, and minimally impactful innovative solution for reinforcing and improving the performance of masonry structures by opening openings in prestressed porous slabs.

The present application relates to the field of coal seam grouting hole sealing, in particular to a kind of radial expansion active pressure grouting hole sealing process, comprising the following steps: step one: construction gas extraction drilling and washing hole to drilling;Step two: the extraction pipe and hole sealing device are sent into drilling;Step three: the mixed slurry of expansion pressure-bearing material and water is injected into hole sealing device and the hole sealing section of drilling using pumping device.When the technical scheme is adopted, it is beneficial to improve the hole sealing effect.

The invention belongs to the technical field of building construction, and relates to a negative pressure type deep hole grouting material and a construction method. The grouting material comprises the following components in parts by weight: 60-70 parts of cement, 3-5 parts of sodium gluconate, 3-15 parts of hydrophobic fibers, 10-18 parts of silicon dioxide, 20-25 parts of fly ash, 1.5-5 parts of a thickening agent, 0.01-1 part of a water reducing agent, 0.01-1 part of an expanding agent and 50-70 parts of water. The grouting material is improved, sodium gluconate, hydrophobic fibers and silicon dioxide are added at the same time, and the adding amount is controlled, so that the grouting material is more suitable for negative pressure grouting, and the problem of concrete holes is solved.

The invention discloses an integrated repairing device for pothole pavement construction and a repairing method thereof, and relates to the technical field of pavement grouting repairing. The integrated repairing device for pothole pavement construction comprises a bottom plate; the universal wheels are mounted on the left and right sides of the bottom of the bottom plate; the pushing handle is mounted on one side of the top of the bottom plate; the stirring tank structure is mounted on the other side of the top of the bottom plate and positioned on the side of the pushing handle; the integrated stirring and grouting structure is connected with the stirring tank structure, the stirring tank structure is communicated with the integrated stirring and grouting structure, and the integrated stirring and grouting structure comprises an automatic stirring assembly arranged in the stirring tank structure. According to the automatic grouting device, the mode that the slurry is sprayed through gas mixing is adopted, the pressure generated when the slurry is injected into the holes of the road surface is reduced, low-pressure grouting is achieved, the risk that a soil layer around the road surface is damaged is reduced, the uniformity of the grouting material is guaranteed to the maximum extent, and the effect and efficiency of automatic grouting operation are improved.

The invention discloses a temporary supporting method for an existing bridge in a narrow space, and relates to the technical field of excavation of foundation pits in the narrow space. According to the temporary supporting method for the existing bridge in the narrow space, bridge protection piles and a top beam are arranged to form an integral retaining wall; a staged pressure grouting technology is adopted to carry out preliminary consolidation, reinforcement and dynamic regulation and control on a soil body, and targeted compensation grouting is carried out in combination with real-time monitoring data, so that active deviation correction control on the posture of a bridge is realized. Safety and stability of the existing bridge in excavation of the foundation pit in the narrow space can be guaranteed.

The application relates to the technical field of tree root piles and discloses a full-casing follow-up tree root pile construction method based on intelligent control, which comprises the following construction steps: 1) a top drive power head vertically drills a casing into a stratum; 2) first hole cleaning; 3) a grouting pipe is lowered, and a filling space is formed between the grouting pipe and the casing; 4) gravel is filled into the filling space; 5) the top drive power head pulls out the casing from a pile hole; 6) a temporary pile casing is placed to supplement the gravel; 7) a hole sealing device is installed at the upper portion of the lumen of the grouting pipe; 8) second hole cleaning; 9) one-time normal-pressure grouting and second-time high-pressure grouting are sequentially carried out in the grouting pipe through a grouting device until the slurry overflows the top of the pile hole; and 10) the hole sealing device is taken out, the slurry is mixed with the gravel to be coagulated to form a tree root pile. The full-casing follow-up tree root pile construction method based on intelligent control has the technical effects of intelligent construction, high construction efficiency and good pile forming quality.

The invention discloses a large longitudinal slope simply supported steel truss girder high-position girder falling construction method, which relates to the technical field of bridge construction, and comprises the following steps: S1, arranging a girder falling supporting point position, manufacturing a girder falling support and supporting a steel truss girder; s2, synchronous jacking, local falling, section drawing and re-jacking are circularly and alternately conducted through a beam falling support at one end of the steel truss beam till first-stage beam falling is completed; s3, a jack arranged on a high pier end padstone of the steel truss girder is dismantled, girder falling continues, and second-stage girder falling is completed; s4, synchronous jacking, local falling, section drawing and re-jacking circulation are conducted through a beam falling support at the low pier end of the steel truss beam till third-stage beam falling is completed; s5, the jack arranged on the low pier end padstone of the steel truss girder is dismantled, girder falling continues, and fourth-stage girder falling is completed; s6, pressure grouting is conducted on the anchor bolt holes, other facilities are dismantled, and construction is completed; the technical problems that in the prior art, beam falling of a large-span steel truss girder bridge is difficult to control, and efficiency is low are solved.

The application discloses a variable-diameter multilayer bidirectional inter-shearing stirring drilling machine, which comprises a drilling machine frame, a drill rod assembly, a power unit, a bidirectional inter-shearing stirring drill bit, a rotary jet variable-diameter unit and a grouting unit. The bidirectional inter-shearing stirring drill bit is driven by the power unit to stir in two directions. The power unit is suspended and connected to the drilling machine frame. The high-pressure rotary jet grouting channel of the rotary jet variable-diameter unit is arranged in the inner drill rod, the high-pressure rotary jet grouting port is arranged between the outer stirring frame of the bidirectional inter-shearing stirring drill bit and the drilling blade, and the curing agent slurry is sprayed out from the high-pressure rotary jet grouting channel to the high-pressure rotary jet grouting port through the high-pressure rotary jet faucet. Under the action of the power unit, the multilayer bidirectional inter-shearing stirring and the rotary high-pressure jetting are realized, and the variable-diameter bidirectional stirring pile is formed. The application also provides a variable-diameter multilayer bidirectional inter-shearing stirring construction method. The variable-diameter amount of the pile can be accurately adjusted by the high-pressure grouting pump, and the variable-diameter grouting can be realized in the designed pile section by controlling the construction parameters.

The application belongs to the technical field of road engineering and foundation treatment, and provides a wind-sand composite roadbed resource intelligent grouting construction method and equipment, which comprises the following steps: after the foundation is leveled, wind-sand is used as the main filler to carry out layered paving and compaction of embankment and lower roadbed; grouting point positions are laid out on the lower roadbed layer; high-performance slurry is used to carry out pressure grouting, and based on the real-time collection results of the compaction degree, the penetration pressure-depth curve, the grouting flow, the lifting speed and the grouting amount per unit depth, the opening and closing of the grouting valve, the grouting pressure and the lifting speed are interlocked controlled or adaptively adjusted to form a continuous and uniform cement column reinforced body; the column top is controlled to be higher than the top surface of the lower roadbed to form a protruding section and is maintained until the preset strength is reached; then, geogrid is laid to make the column top protruding section penetrate and embed in the grid mesh, and the upper roadbed and the pavement structure are continuously constructed; the application takes into account the resource utilization of wind-sand, the collaborative utilization of industrial solid waste and the intelligent control in the construction process.