What accidents will occur in the construction of high pressure jet grouting piles

Rotary grouting pile: It is a special sprinkler that uses a high-pressure pump to pass the cement slurry through the end of the drill pipe and spray it into the soil at high speed horizontally, with the help of the impact force of the liquid.

Cutting the soil layer, at the same time, one side of the drill pipe rotates at a certain speed (20r min), and one side is slowly lifted at a low speed (15 30cm min), so that the soil and the cement slurry are fully stirred, mixed and solidified, and a cylindrical consolidated body (i.e., rotary grouting pile) with a certain strength is formed, so that the foundation is reinforced. The characteristics of the jet grouting pile are: it can improve the shear strength of the foundation.

It can use small-diameter borehole rotary spraying into a large-diameter consolidated body that is 8 10 times larger than the hole, which can be used for the reinforcement of the existing building foundation without disturbing the nearby soil; Low construction noise and low vibration; It can be used in any soft soil layer and can control the reinforcement range; The equipment is simple, lightweight, and has a high degree of mechanization; The material source is broad, the construction is simple, the speed is fast, and the cost is low. Deep cement mixing pile: suitable for dealing with normal consolidated silt and silty soil, plain fill, silt, cohesive soil and loose sand without flowing groundwater.

The depth of reinforcement is generally greater than that of the construction method, and according to the state of the reinforcement materials used, it can be divided into two types of construction: slurry mixing method (wet method, that is, deep cement slurry mixing method in these rules) and powder mixing method (dry method). According to the engineering geological conditions of the site and the load requirements of the superstructure and the cement soil pile.

The cement soil formed by the deep mixing pile is solidified, which can be used as the enclosure retaining wall and anti-seepage curtain of foundation pit engineering; vertically bearing composite foundations; Large-volume cement-stabilized soil.

Wait. The shape of deep stirring and solidification: it can be divided into columnar, wall, grid and block, etc. Among them, the columnar and solid form is mostly used for soft soil reinforced composite foundations; Wall-shaped, grid-like and solid form, mainly used as a deep foundation pit.

excavated retaining walls and anti-seepage curtains; In the form of block and solid, it is mostly used for the foundation of structures with large load per unit area of superstructure and strict control of uneven settlement. However, regardless of the form of solidification, the construction of deep mixing piles has the characteristics of fast pile forming speed, high efficiency, low cost, no vibration, no noise and no pollution. High-pressure jet grouting pile for enclosure structure.

It is suitable for the treatment of silt, silty soil, flow plastic, soft plastic or plastic cohesive soil, plain fill, silt, sand, gravel soil and other soil layers, and when the soil layer contains more large particle size stones, a large number of plant rhizomes or more organic matter and the groundwater flow rate is too large, it needs to be used cautiously or according to the field test results to determine its applicability. In terms of construction methods, the single-pipe method, double-pipe method and triple pipe method can be used respectively; In the form of spraying, it can be divided into three types: rotary spraying, fixed spraying and pendulum spraying, and the reinforcement depth is generally greater than its characteristics of fast pile forming speed, high efficiency, no vibration and no noise in construction; However, there is a lot of loss (waste) of cement slurry during construction, which will cause a certain range of construction environment pollution. Jet grouting pile (solidified):

It can be used for foundation reinforcement of existing buildings and new buildings, soil reinforcement or waterproofing of deep foundation pits, subways and other projects. In the foundation pit enclosure project, it is mostly used as an anti-seepage curtain wall in the form of fixed spraying or pendulum spraying, or used as an anti-seepage retaining wall in conjunction with anti-volcanic piles (directional swing spraying between piles).

In the event of an accident during construction, (construction enterprises) shall take emergency measures to reduce personnel and accident losses, and report to the relevant departments in a timely manner in accordance with relevant national regulations. Constructioncompany refers to an enterprise specializing in the new construction, expansion, reconstruction and demolition of buildings and structures (construction works, municipal public works, lines, pipelines and equipment installation works and decoration works).