1、 Foundation seepage treatment of jet grouting technology in Manas County dry reservoir of Kazi Beach Autor: Yongzhi,Quan Posted:2010-12-14 Abstract According to the Geological Survey and the topography, soil analysis, in the dry mountain reservoir clamp Manas Beach Reservoir dam foundation gravel mi
2、xed soil using high pressure jet grouting method of seepage, leakage passage completely cut off, resolved dam leakage and leakage around the dam. Keywords: high pressure jet grouting； dam leakage； design； construction； Manas； dry clamp Beach Reservoir 50 to 70 years of the 20th century the construct
3、ion of a large number of reservoir engineering, in view of time constraints, many works on the foundation seepage control measures are inadequate, resulting in more serious foundation seepage problems. To give full play to project benefits, the project design criteria safe operation, summary, Applic
4、ation and promotion of new technologies embankment reinforcement is very important 1-2. high-pressure jet grouting is the dam reinforcement of a new technology, with good technical and Economic performance, good anti-seepage effect wide range of applications. jet grouting is a high-pressure slurry u
5、sing high pressure water or high-speed jet beam forming, impact, cutting, crushing the soil strata and filled with cement grout matrix, mixing them, (slightly) the wall-like condensation body, to increase the bearing capacity of foundation seepage or construction Technology 3-4. The Technology of th
6、e original structure of the small dam construction is relatively simple, relatively low construction cost, reinforcement of foundation seepage control has an obvious the technical superiority of 5. the author of Manas County reservoir dry beach profile clamp its Application Technology are summarized
7、 below. 1 Project Overview Manas County Reservoir is dry seat clamp Beach mountain reservoir, located in Manas County Kazakh Autonomous County of the dry beach clamp 22 km southeast of the hilly area, geographic coordinates of latitude 43 5750 , longitude 86 1321 . The works commenced in May 1995, c
8、ompleted in August 1997, September 2008 to reinforce the reservoir dam and the drainage culvert from the hub of the composition. height of 20.1 m, dam length 267.7 m, the total reservoir storage capacity of 110.69 million m3, reservoir control irrigation area 1 333.3 hm2. and other small reservoirs
9、are (1) type project, four main buildings, secondary structures 5. 1.1 The topography Dry clamp Beach Reservoir in large landscapes in the western Tianshan Mountains South of Junggar Basin depressions before the mountain hills, the terrain southeast to northwest descending slope, by tectonic movemen
10、t, the local formation of rows of parallel before the Shan Pui monoclinic structure, the former with the uplift of mountain uplift, mainly because of Mesozoic and Cenozoic mudstone, sandstone, etc., outside the dynamic geological processes of erosion, the formation of hilly topography, landforms man
11、ifested as bread or mountain-like terrain with depressions and white beam topography, library Area terrain elevation 1 336 1 372 m, relative height of 50 70 m, the surface are thick loess cover, topography, ditch white beam topography cutting weaker, and often showed a U shaped valley, not deep gull
12、ies cutting The total is more gentle terrain. 1.2 lithology Exposed strata dam site is mainly Pliocene Tertiary Dushanzi group (N2d) red or grass green mudstone, thin-bedded, and sometimes there are the light gray, brown muddy sandstone and mudstone weathering of the surface often in powder form, st
13、rong weathering zone thickness is 1.0 1.5 m, more complete fresh rock, rock occurrence for the 110 NE 52 , the overlying Quaternary loess and aeolian deposits of ice water, cover thickness 7 17 m. Reservoir left bank of the existence of a nearly north-south depression, depression at the bottom eleva
14、tion of 1 338 1 354 m. elevation of the left bank of bedrock outcrop reservoir bank upstream from the left abutment to the slow uplift, usually 1 340 1 356 m, lower than normal reservoir design Water Level Elevation. upper most bedrock covered by loess, loess thickness is 6 15 m, the loess layer bas
15、ed on the physical and mechanical properties of the loess layer is a medium to high compression, strong collapsible soil, water immersion will likely lead to leakage around the dam break, the need for reinforcement layer of loess. particularly starting from the left abutment, upstream along the slop
16、e about 100 m, mudstone and soil layer in between the gravel layer, thickness 0.6 4.5 m, is a medium to strong water permeability in the reservoir normal operation, the leakage may occur adjacent valley. According to geological survey data on experts, through the soil, rock and reservoir operation i
17、n areas such as during the analysis of the situation, and after calculation of many discussions, suggested that the use of jet grouting dam foundation treatment. 2 Design of jet grouting (1) processing range. According to the geological exploration, reservoir dam and the soil layer between the mudst
18、one gravel mixed with soil, so the foundation of the whole dam jet grouting of dam foundation, the bedrock cut-off wall depth 0.5 m. (2) wall structure. High pressure jet grouting piles connected into a cylinder cut-off wall structure. (3) slurry material selection. The works to the main purpose of
19、seepage, the use of ordinary portland cement, strength class R 32.5. Water-cement ratio (weight ratio) is 1:1, the cement slurry mixed with 20% to 30% bentonite (representing the percentage of cement weight), increased wall seepage performance. cement slurry specific gravity of about 1.6. (4) hole p
20、itch. Using a single arrangement of holes drilled hole distance 0.8 m. (5) the main technical indicators. Construction is divided into two procedures, the first hole for the construction sequence , order to conduct the construction hole, each hole interval sequence at least 14 d. slurry pressure 30
21、MPa, water 60 L / min , nozzle diameter of 2 mm； pump pressure 0.7 MPa, volume 2 m3/min, nozzle diameter 2 mm； injection pipe lifting speed 10 30 cm / min, swing speed of 10 20 r / min. pile permeability coefficient is less than 10 - 6 cm / s, the effective diameter of the pile is not less than 1.0
22、m, the minimum lap width of 20 cm, the compressive strength R 28 = 5 MPa. (6) high pressure jet grouting quality control of automatic detection units. Shunt connection with the construction equipment, the parameter indicators include gas, pulp 2 medium pressure, flow rate, slurry specific gravity, i
23、ncrease speed, cement, soil feeding amount, etc. can be displayed directly in the construction process, and continuous recording. 3 high-pressure jet grouting To ensure the quality of jet grouting to be based on different geological conditions, to determine reasonable parameters of jet grouting, targeted use of different construction techniques to ensure quality of construction projects. To meet the design requirements of the premise should be review of the first
