CN204456058U - A kind of constructing structure reducing building base subsidence speed - Google Patents

Abstract

The utility model provides a construction structure for reducing the settlement rate of building foundations, which includes a building floor, and a floor settlement area is formed on the edge of the building floor. The bottom of the building floor is filled with an expanded concrete layer, and steel bars are laid in the expanded concrete layer. The pile body of the micro-steel pipe pile extending to the bottom of the expanded concrete layer is a melon stone pile body, and the high-pressure rotary grouting pile extends to the pile below the expanded concrete layer. The body is a cement-soil pile body, and a cement grouting pipe extending from the surface of the building floor is arranged in the middle of the micro-steel pipe pile and the high-pressure jet grouting pile. The technical effect of the utility model: the construction structure of the utility model is convenient in construction and simple in structure. Reduce the settlement rate of the building foundation and control the uneven settlement to ensure the safety and reliability of the foundation structure.

Description

A Construction Structure for Reducing the Settlement Rate of Building Foundation

technical field

The utility model relates to the field of building foundation construction, in particular to a construction structure for reducing the settlement rate of building foundations.

Background technique

With the rapid development of the construction industry, the development and utilization of underground space is an important way for the current urban three-dimensional development. In recent decades, although the scale and intensity of urban underground space development and construction in my country have become larger and larger, the planning, management and The construction of laws and regulations is seriously lagging behind, and relatively complete and scientific research on the evaluation techniques and methods of underground space land price system is rarely seen, which has become an important bottleneck restricting the sustainable development, utilization and scientific management of urban underground space. Scholars at home and abroad have found through research and experiments that there are still many problems in the theory and practice of building foundation settlement analysis. The large difference between theoretical calculation and practical results, too large range of empirical coefficients, etc., all make the calculation of building foundation settlement a difficult problem in the theoretical research of building foundation.

The settlement of the building foundation can affect the safety of the building structure. There are also construction structures on the market that can reduce the settlement rate of the building foundation. However, the existing construction structures are difficult to construct and have complex structures, and the effect of reducing the settlement rate of the building foundation is not significant enough.

Utility model content

According to the deficiencies of the prior art, the utility model provides a construction structure for reducing the settlement rate of the building foundation. The structure is simple, the construction is convenient, the safety of the building structure is ensured, and the effect of reducing the settlement rate of the building foundation is achieved.

The technical scheme of the utility model: a construction structure for reducing the settlement rate of the building foundation, including a building floor, and a floor settlement area is formed on the edge of the building floor, which is characterized in that a micro-steel pipe pile and a high-pressure Rotary grouting piles, the bottom of the building floor is filled with an expanded concrete layer, and steel bars are laid inside the expanded concrete layer. The pile body that extends to the bottom of the expanded concrete layer is a melon stone pile body, and the high-pressure rotary grouted pile extends to the expanded concrete layer. The pile body below is a cement-soil pile body, and a cement grouting pipe extending out of the building floor surface is arranged in the middle of the micro-steel pipe pile and the high-pressure rotary grouting pile.

Micro-steel pipes are installed on the periphery of the micro-steel pipe pile body, and the two micro-steel pipes are connected by outer hoop joints.

The distance between the micro-steel pipe pile and the high-pressure rotary grouting pile is 2.5m-3.8m.

The pile diameter of the high-pressure rotary grouting pile is 600mm, and the pile length is 30m; the pile diameter of the micro steel pipe pile is 220mm, and the pile length is 17.5-21.5m.

The diameter of the micro-steel pipe is 194mm, the wall thickness is 5mm, and the length of the micro-steel pipe is 3m.

The technical effect of the utility model: simple structure, convenient construction, ensuring the safety of the building structure, plastic and soft plastic powdery clay layer and silt layer in the rock-soil foundation reinforced by high-pressure rotary jetting piles; miniature steel pipe piles strengthen the rock-soil foundation The weak clay layer is used to strengthen the foundation and raft to resist pullout and reduce differential settlement, so as to reduce the settlement rate of the building foundation and control uneven settlement to ensure the safety and reliability of the foundation structure.

Description of drawings

Fig. 1 is a schematic diagram of floor structure of the present utility model;

Fig. 2 is a schematic diagram of the overall structure of the utility model;

Fig. 3 is a schematic diagram of the utility model pile body structure;

Fig. 4 is a schematic diagram of the connection of the micro-steel pipe of the present invention.

The labels in the figure respectively indicate: 1—building floor, 2—settlement area, 3—miniature steel pipe pile, 4—high pressure jet grouting pile, 5—rebar, 6—expanded concrete layer, 7—guami stone pile body, 8— Cement-soil pile body, 9—miniature steel pipe, 10—outer hoop joint, 11—cement grouting pipe.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described:

As shown in Figures 1 to 4, a construction structure for reducing the settlement rate of building foundations includes a building floor 1, and a floor settlement area 2 is formed on the edge of the building floor 1, and it is characterized in that: below the floor settlement area 2, there are The micro-steel pipe pile 3 and the high-pressure rotary grouting pile 4, the bottom of the building floor 1 is filled with an expanded concrete layer 6, and steel bars 5 are laid in the expanded concrete layer 6, and the pile body extending to the bottom of the expanded concrete layer 6 is a melon. Rice stone pile body 7, high-pressure rotary grouting pile 4 extending to the pile body below the expanded concrete layer 6 is cement soil pile body 8, in the middle of the micro-steel pipe pile 3 and high-pressure rotary grouting pile 4 is provided with a surface that extends out of the building floor 1 The cement grouting pipe 11.

The periphery of the pile body of the micro-steel pipe pile 3 is equipped with micro-steel pipes 9, and the two micro-steel pipes 9 are connected by outer hoop joints 10.

The distance between the micro-steel pipe pile 3 and the high-pressure jet spray pile 4 is 2.5m-3.8m.

The pile diameter of the high-pressure rotary grouting pile 4 is 600mm, and the pile length is 30m; the pile diameter of the micro steel pipe pile 3 is 220mm, and the pile length is 17.5-21.5m.

The diameter of the micro-steel pipe 9 is 194mm, the wall thickness is 5mm, and the section length of the micro-steel pipe is 3m.

After uneven settlement of the building foundation, the high-pressure jet grouting piles and micro-steel pipe piles are first laid out on the building floor. High-pressure rotary grouting piles: manually excavate the building floor, remove concrete and steel bars, and use diamond drilling to drill holes with a diameter of 220mm. The mixing ratio is 15%-30%, the grouting pressure is not less than 22Mpa, and the water-cement ratio is 0.75. The pile tip enters the medium-dense sand layer for 1.5m, and the ash-stopping elevation is the bottom of the floor. Seven days after the completion of the construction, the pile head was closed, the floating slurry and residues were removed, the floor reinforcement was repaired and welded, the high-pressure grouting pipe was reserved, and C40 expansive concrete was poured and compacted to the top of the slab. After 20 days of concrete curing, high-pressure grouting is carried out, and the water-cement ratio is 0.9. The purpose is to prevent the shrinkage of the pile body and slow down the settlement of the floor.

Miniature steel pipe piles: diamond drilling is used to drill holes with a diameter of 220mm and a depth of 17.5-21.5m. After the hole is formed, a steel pipe with a diameter of 194mm and a wall thickness of 5mm is placed. The length of the steel pipe is 3m. Install. After the steel pipe is placed, inject clean water from the grouting pipe, discharge the mud in the pipe, manually put melon stones into the pipe mouth, and then press grout to the pipe mouth. The water-cement ratio is 0.6. After 7 days of grouting, start to close the pile head, remove the laitance and residue, repair and weld the floor reinforcement, pour C40 expansive concrete and tamp it to the top of the slab.

Example: The Wuhan Wangjiadun Park project is located in the northwest corner of the Wangjiadun CBD business district. It is mainly composed of 5 artificial peaks and two semi-buried underground buildings A and B. The geology is mainly: silty clay layer and silty clay layer. thick, the soil layer undulates greatly, and the bearing capacity is poor, which has a great influence on the settlement of the foundation. Among them, the underground building structure of B is a reinforced concrete structure, 114m long, 72m wide, 12m high, and the top of the building is covered with soil at a height of 5m. The building foundation treatment method adopts the method of sand and gravel pile + sand and gravel cushion + surcharge preloading. After the building of site B is completed (the post-pouring zone is not sealed), the settlement difference between the east and west directions is obvious, which affects the structural safety. The main characteristics are the high settlement rate of the foundation and the uneven settlement area of the foundation. The utility model is selected to focus on solving the problem of excessive settlement rate of the building. The utility model can improve the settlement of the foundation through partial adjustment of the foundation; the construction cost is controllable, more economical and affordable, and the overall construction period is not greatly affected; scientific and reasonable treatment methods are selected to ensure reliability and meet the interests of multiple parties; it is feasible, economical and reliable sex is better.

A construction structure for reducing the settlement rate of building foundations of the utility model has simple structure, convenient construction, and ensures the safety of building structures. Plastic and soft plastic powdery clay layers and silt layers in rock-soil foundations reinforced by high-pressure rotary grouting piles; micro-steel Pipe piles are used to strengthen the weak clay layer in the rock-soil foundation, to strengthen the foundation and raft to resist pullout, and to reduce differential settlement, so as to reduce the settlement rate of the building foundation and control uneven settlement to ensure the safety and reliability of the foundation structure.

Claims (5)

1. A construction structure for reducing the rate of settlement of building foundations, comprising a building floor (1), forming a floor settlement zone (2) on the edge of the building floor (1), characterized in that: the floor settlement zone (2) is arranged below the floor settlement zone (2) There are micro-steel pipe piles (3) and high-pressure jet grouting piles (4), the bottom of the building floor (1) is filled with an expanded concrete layer (6), and steel bars (5) are laid in the expanded concrete layer (6), and the micro-steel pipe piles (3) The pile body extending to the bottom of the expanded concrete layer (6) is a melon stone pile body (7), and the pile body extended to the bottom of the expanded concrete layer (6) by the high-pressure rotary grouting pile (4) is a cement-soil pile body ( 8), a cement grouting pipe (11) extending out of the surface of the building floor (1) is provided in the middle of the miniature steel pipe pile (3) and the high-pressure jet grouting pile (4). 2. A kind of construction structure that reduces building foundation settlement rate according to claim 1, is characterized in that: the periphery of described micro-steel pipe pile (3) pile body is equipped with micro-steel pipe (9), micro-steel pipe (9) Connect by outer hoop joint (10) between two. 3. A construction structure for reducing the settlement rate of building foundations according to claim 1, characterized in that the distance between the miniature steel pipe piles (3) and the high-pressure jet grouting piles (4) is 2.5m to 3.8m. 4. a kind of construction structure that reduces building foundation settlement rate according to claim 1, is characterized in that: the pile diameter of described high-pressure rotary grouting pile (4) is 600mm, and pile length is 30m; Miniature steel pipe pile (3 ) with a pile diameter of 220mm and a pile length of 17.5-21.5m. 5. A construction structure for reducing the settlement rate of building foundations according to claim 2, characterized in that: the micro-steel pipe (9) has a diameter of 194mm, a wall thickness of 5mm, and a length of 3m of the micro-steel pipe section.