US 11,987,948 B2
Pumping method of large-diameter horizontal pressurized long dewatering well for inexhaustible pumping strata
Shiming He, Beijing (CN); Dangsheng Guo, Beijing (CN); Jiang Li, Beijing (CN); Fengchen Yang, Beijing (CN); Yucheng Zhou, Beijing (CN); Hekun Yu, Beijing (CN); Hui Chen, Beijing (CN); Xinfeng Huang, Beijing (CN); Chenghua Liang, Beijing (CN); and He Huang, Beijing (CN)
Assigned to SINOMA GEOLOGICAL ENGINEERING EXPLORATION AND RESEARCH INSTITUTE CO., Beijing (CN); BEIJING BUILDING MATERIALS AND GEOLOGICAL ENGINEERING CO., Beijing (CN); and BEIJING CITY CONSTRUCTION TECHNOLOGY PROMOTION ASSOCIATION, Beijing (CN)
Filed by Sinoma Geological Engineering Exploration and Research Institute Co., Beijing (CN); Beijing Building Materials and Geological Engineering Co., Beijing (CN); and Beijing City Construction Technology Promotion Association, Beijing (CN)
Filed on Apr. 11, 2022, as Appl. No. 17/717,819.
Claims priority of application No. 202110657097.3 (CN), filed on Jun. 11, 2021.
Prior Publication US 2022/0396927 A1, Dec. 15, 2022
Int. Cl. E02D 31/00 (2006.01); E02D 31/02 (2006.01)
CPC E02D 31/02 (2013.01) 3 Claims
OG exemplary drawing
 
1. A pumping method of a large-diameter horizontal pressurized long dewatering well for inexhaustible pumping strata, comprising the following steps:
S1: excavating a side wall of a foundation pit by determining an accurate position according to an investigation report and a site, and determining positions of each clay layer and sand soil layer according to a construction position of the foundation pit;
S2: putting a drilling rig with simultaneous casing, a water pump, an air compressor and other equipment in place, installing and debugging;
S3: measuring and setting-out for positioning holes and locating a horizontal position at a junction of the clay layer and the sand soil layer; carrying out horizontal drilling in sand soil layers containing an aquifer by using the drilling rig with simultaneous casing, and after reaching a designed depth, drawing out an inner pipe, placing horizontal wells, and then drawing out a casing; situating the horizontal wells above a junction of clay layers and the sand soil layers, so that all the horizontal wells including drain pipes and air ducts are completely in the aquifer; sealing around openings of the drain pipes and the air ducts in a radial direction of 10 cm-20 cm;
S4: corresponding the horizontal wells to an upper row of soil nails or anchors; with soil nails or prestressed anchor cables already arranged in the clay layers of the side wall of the foundation pit, getting the horizontal wells longitudinally aligned with the soil nails or prestressed anchor cables on the side wall of the foundation pit, and getting a depth of the horizontal wells equal to a length of the soil nails or prestressed anchor cables, so that a bearing capacity is not reduced;
S5: arranging one of the air ducts in the middle of every two long wells, so as to ensure that the air ducts bare in the aquifer, getting the drain pipes and the air ducts at the same elevation; getting each air duct between the drain pipes, to make the air ducts in the aquifer;
S6: carrying out construction work on the horizontal wells;
S7: carrying out the construction work on pressurized holes;
S8: connecting the air compressor and the air ducts to inflate and pressurize, discharging water in long horizontal wells into a collecting ditch, gathering water in a collecting well for pumping out and draining; connecting the air ducts with an air pipe of the air compressor through a reducing joint, so as to inflate and pressurize the aquifer; discharging the water into the collecting ditch by the drain pipes, gathering the water in the collecting well and pumping out the water to ensure a dry operation in the foundation pit, and contribute to controlling the settlement deformation of surrounding environment.