A method for improving ground is capable of preventing a clod whose representative size is large from remaining in the ground. The method for improving ground includes cutting a ground by injecting a cutting fluid (e.g. high-pressure water or high-pressure air: including a case where a solidification material is injected) from jet devices, feeding a solidification material, mixing the cut ground, the cutting fluid and the solidification material, and agitating a mixture thereof to form an underground consolidated body. A plurality of nozzles are located at an interval in a vertical direction in the jet devices, and when the cutting fluid is injected, a cutting fluid is injected from an upward nozzle in a downward skewed direction, and a cutting fluid is injected from a downward nozzle in an upward skewed direction.

There is disclosed a steel pipe pile with spiral blades which is capable of effectively improving comparatively soft ground in which a clay layer and the like are present at deep positions of several ten meters beneath the surface of the ground. A steel pipe pile 1 with spiral blades comprises a steel pipe pile main body 10 and one or more spiral blades 20 attached to the steel pipe pile main body 10, and a diameter D of the spiral blade 20 is set to three times or more as large as a diameter d of the steel pipe pile main body 10.

A high pressure injection flushing head includes a flushing body comprising an upper body portion, and a lower body portion coupled to the upper body portion. The upper body portion and the lower body portion cooperate to define a bore. A shaft is rotatably disposed at least partially within the bore. A plurality of rotary elements are configured to facilitate rotational movement of the shaft relative to the flushing body. The flushing body comprises a lubrication system having a plurality of grease nipples, and a network of pathways in fluid communication with the grease nipples that are configured to deliver grease to the rotary bearings. The flushing head couples to an adapter via a flanged connection so that the flushing head can be adapted for use with a plurality of drill rod types.

A high pressure injection flushing head includes a flushing body comprising an upper body portion, and a lower body portion coupled to the upper body portion. The upper body portion and the lower body portion cooperate to define a bore. A shaft is rotatably disposed at least partially within the bore. A plurality of rotary elements are configured to facilitate rotational movement of the shaft relative to the flushing body. The flushing body comprises a lubrication system having a plurality of grease nipples, and a network of pathways in fluid communication with the grease nipples that are configured to deliver grease to the rotary bearings. The flushing head couples to an adapter via a flanged connection so that the flushing head can be adapted for use with a plurality of drill rod types.

A device (10) for treating a portion of soil comprises a rotary shaft (20), at least one deployable mixer tool (40) secured to the rotary shaft (20), and a longitudinal pipe (22) for injecting a fluid in the proximity of the mixer tool (40). According to the invention, the treatment device (10) further includes a boring tool (24) situated at the bottom end of the shaft (20), an outer tubular element (30) extending parallel to the rotary shaft (20), the rotary shaft (20) being arranged inside said tubular element (30), and a coupling system (50) between the rotary shaft (20) and the tubular element (30). In a first configuration, the coupling system (50) is suitable for constraining the tubular element (30) and the rotary shaft (20) to move together in rotation about the main axis (X), in at least one direction of rotation, and for constraining the tubular element (30) and the rotary shaft (20) to move together in translation along the main axis (X), at least in the downstream direction. These movements in rotation and translation can be released in a second configuration of the coupling system (50).

A device (10) for treating a portion of soil comprises a rotary shaft (20), at least one deployable mixer tool (40) secured to the rotary shaft (20), and a longitudinal pipe (22) for injecting a fluid in the proximity of the mixer tool (40). According to the invention, the treatment device (10) further includes a boring tool (24) situated at the bottom end of the shaft (20), an outer tubular element (30) extending parallel to the rotary shaft (20), the rotary shaft (20) being arranged inside said tubular element (30), and a coupling system (50) between the rotary shaft (20) and the tubular element (30). In a first configuration, the coupling system (50) is suitable for constraining the tubular element (30) and the rotary shaft (20) to move together in rotation about the main axis (X), in at least one direction of rotation, and for constraining the tubular element (30) and the rotary shaft (20) to move together in translation along the main axis (X), at least in the downstream direction. These movements in rotation and translation can be released in a second configuration of the coupling system (50).

A drilling and grouting device comprises a drill string including a hollow elongate outer rod having a central axis and a hollow elongate inner rod located coaxially within said outer rod, wherein a first outer flow path is defined between said inner and outer rod, and a first central flow path is defined inside said inner rod, a drill bit aligned with said inner rod along said central axis and including a second central flow path, and a crossover part interposed between said inner rod and said drill bit along said central axis, which is configured to connect the first central flow path with a second outer flow path surrounding the drill bit to form a main path and to connect said first outer flow path with said second central flow path to form a secondary path. Also disclosed are systems and methods that include and use the device.

A drilling and grouting device comprises a drill string including a hollow elongate outer rod having a central axis and a hollow elongate inner rod located coaxially within said outer rod, wherein a first outer flow path is defined between said inner and outer rod, and a first central flow path is defined inside said inner rod, a drill bit aligned with said inner rod along said central axis and including a second central flow path, and a crossover part interposed between said inner rod and said drill bit along said central axis, which is configured to connect the first central flow path with a second outer flow path surrounding the drill bit to form a main path and to connect said first outer flow path with said second central flow path to form a secondary path. Also disclosed are systems and methods that include and use the device.

A pile includes a first pile section having a first end that engages a supporting medium and an opposing second end. A first end of a second pile section is engageable with the second end of the first pile section, each of the first and second pile sections having mating end fittings that create an interlocking fit. A sleeve overlays the first and second engaged ends of the first and second pile sections. At least one through hole aligned with at least one corresponding through hole of the first pile section is sized for receiving a fastener for securing the sleeve to the first pile section. In another version, the ends of the pile section are engaged in contact while the overlaying sleeve has a pair of interlocking sleeve or coupler portions that are configured to provide torsional resistance. Additional pile sections can be sequentially attached to the second pile section.

The present invention discloses a test system and a test method for detecting the cement content of cement stirring pile body in real time at a construction site. The test system specifically includes a cement slurry density measuring apparatus and a cement admixing amount calculating apparatus. The method includes measuring the density of the cement slurry in the cement slurry tank, measuring the cement soil density and inputting measured values to calculate the cement content. The cement slurry density and the cement soil density can be detected in real time, so that the admixing amount of the cement can be detected in real time during the foundation reinforcing process of the underground engineering, convenience and rapidness are achieved, the time period is short, a supervision effect is good, and cheating on workmanship and materials can be effectively avoided.