30results about How to "Ensure normal excavation" patented technology

The invention provides a vacuum preloading film pressing groove extension construction method which includes the steps of film pressing groove extension and sealing film laying. In the film pressing groove extension step, an original film pressing groove which can not be dug to an airtight layer is horizontally moved to the outer side of a region, and digging is performed after the position of the film pressing groove is determined again so as to guarantee that a sealing film can be pressed in a film pressing groove airtight soil layer after film pressing groove extension. In the sealing film laying step, after film pressing groove extension, the size of the sealing film is adjusted according to actual extension size, the sealing film is laid, and a vacuum preloading construction stage starts after sealing film laying. The vacuum preloading film pressing groove extension construction method is convenient to use, it can be ensured that digging can be performed to the airtight layer, the sealing effect is guaranteed, and the preloading effect of a whole vacuum preloading area is guaranteed.

The invention relates to a foundation pit earthwork construction method for civil air defense engineering, and belongs to the technical field of civil air defense engineering construction. The foundation pit earthwork construction method for civil air defense engineering comprises the steps that step 1, after surveying and setting out of a deep foundation pit are completed, the deep foundation pit is divided into M areas from south to north, each area is divided into N<q> construction sections from west to east, and the corresponding mark number of each construction section is defined as MN<q> (p is larger than 2, q is larger than 4, and p and q are both positive integers); step 2, before the corresponding construction section is excavated, precipitation pipe well construction is conducted on the construction section; step 3, according to a foundation pit design drawing, excavation is conducted in a partitioned, segmented and layered mode from west to east in a backward sequence; when a (q-1) th foundation pit is excavated, layered excavation is carried out from west to east, excavation sections are M<1>N<q-1>, M<2>N<q-1>... MN<q-1> sections, excavation sections of a qth foundation pit are M<1>N<q>, M<2>N<q>... MN<q> sections, layered excavation is carried out from south to north, and riding tracks are arranged at the M<1>N<q> section; and step 4, according to the mode in step 3, excavation of the foundation pit is completed. The construction efficiency can be improved, and the construction quality is guaranteed.

The invention discloses a protective construction method of excavating a large area deep foundation pit in a running sand confined water soil layer. The method comprises the steps of: firstly, controlling the precipitation depth of the deep foundation pit in a range of 500mm to 1000mm below the excavation surface; disposing a circle of sandless tubular wells around the outer periphery of the deepfoundation pit, wherein each sandless tubular well is 2 meters far from the deep foundation pit edge, 6 to 10 meters deeper than the bottom of the deep foundation pit, and 15 to 20 meters far from the neighboring sandless tubular well; laying reinforcing steel mesh sheets and disposing a circle of light-duty wellpoints on an inward side slope of the deep foundation pit; after starting the excavation, arranging a soil nail wall provided with weep holes for anchoring on a side slope of silty sand layer and silty clay layer with silt seam. By the method in the invention, the excavation of the large area deep foundation pit in the running sand confined water soil layer is ensured to be smooth, with no need to enlarge the excavation area. The difficulty of construction and the construction cost are lowered and the construction period is shortened.

The invention discloses an underwater large-diameter shield continuous excavation construction tool with a deformed tail shield, which includes a water delivery unit, a plurality of high-pressure water bladders and a plurality of guide strips, and the high-pressure water bladders are respectively fixed on the inner wall of the tail shield shell , and is located between the inner wall of the tail shield shell and the outer peripheral surface of the segment ring. The water delivery unit includes industrial water tanks, input water pipes, high-pressure water pumps, output water pipes and end hoses. A group of several high-pressure water bag input water pipes are connected in parallel to form a total input water pipe. The end hose of the water delivery unit passes through a quick connector, the main input The water pipe is connected with a group of several high-pressure water bladders. The construction method of the present invention includes 1) separately installing high-pressure water bladders and connecting them with water delivery units, 2) assembling a segment ring, and 3) sequentially completing the water injection and pressurization of the high-pressure water bladder units in a segment ring. 4) Shield tunneling and monitoring. The invention can prevent the inner wall of the deformed tail shield shell from extruding the tube piece, reduces the damage of the tube piece in the forming tunnel, improves the construction efficiency and reduces the construction cost.

The invention discloses a construction method for an anti-scouring discharge channel of a dammed lake. The side slope steel wire mesh is laid on both side slopes of the discharge channel, a reinforced geomembrane is laid on the bottom of the discharge channel, and a reinforced geomembrane is laid on the side slopes on both sides Reinforced gabions are set at the bottom of the slope, and multiple rows of prefabricated pier stones are set in the discharge channel. A single row of prefabricated pier stones is arranged along the width direction of the discharge channel. A single prefabricated pier stone is fixed at the bottom of the discharge channel through the first anchor rod. Adjacent prefabricated pier stones are connected by second anchor rods, and the second anchor rods close to the slope are fixedly connected on both sides of the slope; the discharge trough constructed by the construction method of the present invention can effectively reduce the scouring intensity of water flow and flow velocity, enhance the anti-scouring ability of the slopes on both sides of the discharge trough and the bottom of the trough, and reduce damage and loss to the downstream. The construction method of the invention has a short construction time, can shorten the emergency preparation time as much as possible, can ensure the excavation of the discharge tank and the reinforcement of the tank body in a short time, and various geotechnical materials used in the construction process are cheap.

The invention relates to a shallow burial soil area shield driving stratum strengthening system and a construction method thereof. Tunneling under the condition of shallow burial soil can lead to disadvantages of unstability and collapse of a shield method tunnel cutting face, upheaval and settlement of earth surface and the like. Uplift piles which are arranged in rows are vertically arranged between a two-way shield tunnel and the two sides of the two-way shield tunnel, the tops of the uplift piles at the two sides are provided with rectangular ring beams, and a two-way multi-ribbed plate is arranged in each ring beam; each two-way multi-ribbed plate is composed of concrete front-panels and two-way multi-ribbed beams which are arranged on the bottom faces of the concrete front-panels, and the two-way multi-ribbed beams are distributed in a transverse and longitudinal crossed grid-shaped mode; the concrete front-panels and the two-way multi-ribbed beams adopt integral formwork erection, and one-time pouring forming is achieved; the ring beams are connected with the two-way multi-ribbed plates to form a whole through rebar connectors reserved in the inner sides of the ring beams. According to the shallow burial soil area shield driving stratum strengthening system and the construction method thereof, stratum upheaval and settlement deformation caused by shield driving pressure under the condition of shallow burial soil can be effectively blocked, the adverse impact on a running tunnel below ground caused by temporary overload on the ground after completion of work can be reduced, and normal driving for the shield tunnel in the shallow burial soil area can be guaranteed.

The invention discloses a construction method for excavating and supporting a foundation pit of a shield receiving well without precipitation. Combined to form the side wall of the foundation pit of the shield receiving shaft; the bottom of the foundation pit and the inner and outer sides of the side wall of the foundation pit are respectively grouted to form a bottom water-stop curtain, an inner water-stop curtain and an outer water-stop curtain, and the water-stop curtain is integrally formed , a gap groove is formed between the water-stop curtains on the inside and outside of the side wall of the foundation pit; the water in the foundation pit is drained, and part of the water in the gap groove is extracted, so that the water level in the gap groove is between the ground level and the bottom surface of the foundation pit, Then construct crown beams and ground water retaining walls; excavate the foundation pit, excavate in layers from top to bottom, and set up multiple supports for each layer. The method of the invention solves the problem of safe construction under the condition of no precipitation during the excavation and support construction of the foundation pit of the shield receiving shaft.

The invention provides a filling device and method for an abandoned air-raid shelter in a pile foundation construction site. The filling method is to drill a grouting hole above the abandoned air-raid shelter to be filled, and install a primary grouting pipe, a secondary grouting pipe, an air supply pipe and an exhaust pipe, a primary grouting pipe and a delivery pipe in the borehole. The air pipe extends vertically into the bottom of the air-raid shelter, and the secondary grouting pipe and exhaust pipe extend vertically to the roof of the air-raid shelter; firstly, the primary grouting pipe is connected to the grouting pump, and the air supply pipe is connected to the air compressor, and the foam is injected in layers Concrete grouting slurry, after each layer of grouting, pull up the primary grouting pipe and the air supply pipe to the top of the cave; then connect the secondary grouting pipe to inject the foam concrete grouting slurry for the second time, and the secondary grouting does not supply air. The invention can solve the filling problem of the deep-buried air-raid shelter without excavation, and the filled construction site can ensure the normal construction of bored piles, which solves the problem that the deep-buried air-raid shelter cannot be normally constructed when the rotary drilling rig is constructing the poured pile foundation and site subsidence.