1、The application of Trenchless technology in engineering Abstract: In recent years, trenchless technology was developed rapidly in our country. Because it damaged environmental small,locate accurate,cost low,didnt affect traffic and its construction period is short .So it was applied more and more in
2、 the underground engineering (such as urban underground pipeline and the subway). This article introduce the Examples of application of pipe jacking method (the common methods of trenchless technology) in urban underground pipeline and subway, and also describes the prospect and the existing problem
3、s of trenchless technology. Key words: Trenchless technology； pipe jacking method 0 lead said Trenchless technology is refers to the use of horizontal directional drilling technical means of the geotechnical dig, on ground not excavation circumstances laying, replacement and repair all sorts of unde
4、rground pipeline construction of new technology. Because trenchless technology has laying pipelines position precision, construction period is short, the environmental damage the small, do not affect traffic and low cost advantages, non-excavation technology has in urban underground pipeline, subway
5、 lines and other engineering has been widely used. Trenchless construction equipment is mainly composed of the following several parts: 1) guidance system: used in drilling process to the drill bit localization to determine the orientation Angle and drilling. By transmitters and receivers, controlle
6、r, remote monitor, power supply etc. 2) host: by the engine, hydraulic system, mud pump, dynamic axis, pipe and loading systems etc. 3) drill bit, back by expanding head, pipe etc. 4) mud mixing system: can increase the drill lubrication, lower drilling resistance and drill working temperature. 1 in
7、 the pipeline trenchless technology project and the application 1.1 project summary Set 1650mm sewage pipe diameters for engineering, pipe jacking pipe using F tube, steel mouth interface, bearing level tube. D1650 844.1 meters, length of pipe jacking slope i=0.6 . Determination of 1.2 pipes Accordi
8、ng to the engineering drawings request, this project the sewage pipe pipe jacking by use of pipes for: using F tube, steel mouth interface, bearing level tube. 130 pipe jacking construction plan, technology and quality control measures Pipe jacking brief Pipe-jacking, pipe jacking diameters for 1650
9、, using slurry balance mechanical roadheader pipe jacking construction. Input 1 1650TLM slurry balance pipe jacking construction operation used in engineering roadheader. The selection of 1.4 pipe jacking equipment and installation 1.4.1 pipe jacking roadheader choice Choose good of pipe jacking roa
10、dheader pipe jacking is vital. According to the landlord will provide the engineering geology exploration manual, geological data shows that this engineering pipe jacking through stratum for silt layer, the permeability coefficient is big, physical and mechanical properties of poor. So, choose a kin
11、d of more advanced fully enclosed mechanical crest Tube roadheader - TLM slurry balance roadheader. The machine has a settlement high control accuracy, of jacking speed, etc. The selection of 1.4 pipe jacking equipment and installation 1.4.1 pipe jacking roadheader choice Choose good of pipe jacking
12、 roadheader pipe jacking is vital. According to the landlord will provide the engineering geology exploration manual, geological data shows that this engineering pipe jacking through stratum for silt layer, the permeability coefficient is big, physical and mechanical properties of poor. So, choose T
13、ube roadheader - TLM slurry balance roadheader. The machine has a settlement high control accuracy, of jacking speed, etc. 1.4.2 Lord of jacking system Settings Lord of jacking system consists of oil cylinder group, of jacking ring, steel, leaning back and hydraulic pump station etc, its main functi
14、on is to GuanJie of jacking, is the main pipe jacking equipment system part. 1) oil cylinder group Oil cylinder by 4 only oil cylinder of decorate symmetrically two columns of points, every column each 2 only oil cylinder fold up into, and the structure of bearing fixed, ce LiangLianCheng one with c
15、onnection. Oil cylinder choose domestic double stroke, double function of each item of hydraulic jack thrust only oil cylinder for maximum thrust 1000KN, equipment for maximum thrust 4000KN, meet the maximum allowable pipe jacking jacking force requirements. Oil cylinder stroke length 2.5 3.0 m, so
16、can a continuous GuanJie of McCains top into complete set, neednt cushion block, high efficiency and reduce labor intensity. 2) hydraulic pump station Choose A2F28RP2 inclined shaft type 2 sets the plunger pump, equipped with Y200L - 6 type motor. Through the speed regulation valves can be changed a
17、ccording to the flow of oil pump, the condition of jacking required to control the main roof oil cylinder top speed. To satisfy the excavation face earth pressure balance conditions, thus plays the role of ground subsidence control. 3) steel, leaning back When GuanJie of jacking the oil cylinder, th
18、rough reverse force after evenly transfer by steel walls to work well, avoid sidewall stress caused by uneven or local stress shaftlining structure, excessive damage. Steel, leaning back when installed, should be vertical axis with top into the gap between borehole wall, and application of conerete,
19、 ensure that the overall contact fill reality. 4) Lord of jacking device main technical parameters Oil cylinder quantity: 4 Oil cylinder size: D x d x L = 2.5 x 220 x 3 500 mm Oil cylinder trip: S = 3 000 m Limited Pressure: P = 25MPa Limit thrust: F = 1500KN Highest pressure: Pmax = 31.5 MPa Maximu
20、m thrust: Fmax =2000KN 1.4.3 sturry unearthed system Telemole facade system adopts the piping system. Slurry pump type: 4/3 C - AH, motor power 18.5 kW, flow 90m / h, head 21.8 m. The pipe jacking construction of efficiency is the effect of tube unearthed by sturry the key link, because piping syste
21、m can make the pipe jacking to achieve continuous advancing. 1.4.4 pipe jacking working pit facilities layout Pit guide should have enough intensity and rigidity. The engineering foundation by steel and steel plates welded rails and into. Based on the work well in bottom plate, embed should be prior
22、 embedded steel consistent position and foundation pit, in order to guide rails and welding. Embedded steel reinforced the anchorage to welded and have enough anchoring strength, guide rail placed the good, still should in two side, with steel support when necessary to ensure slideway pouring the co
23、ncrete again under the condition of the suffers bump, dont move, changeless form. Guide installation the allowable deviation for: axis position: 3mm, top surface elevation: 0 + 3mm, two tracks from: 2mm. In the process of jacking check and recheck frequently. Lord top oil cylinder frame is split typ
24、e structure, main top oil cylinder frame installation also want accurate location. Ensure oil cylinder bearing point is in the correct position. The elevation and plane installation error is less than 5mm. Top iron pipe axis parallel axis should with iron and symmetrical, top, and shall not have con
25、tact between rails soil, smeary； Top iron tube nozzle should adopt the buffer material between line. In of jacking process, staff shall not in top iron, and stay above and side should be observed without anomalies at top iron signs. Confined wall is inherit and pass all the backseat wall jacking for
26、ce, more should have the enough strength and rigidity, and have enough safe degrees. This project in the confined wall lining concrete design of reinforced concrete pouring on first used by steel flat, and with the delta = after 70 steel, steel and concrete planar in full 50 plank. Between lining 1.
27、5 of jacking construction technology, technical quality control measures 1.5.1 pushing force and maximum limit measures Engineering Lord top hydraulic system work well pushing force according to the maximum allowable jacking force of 1000KN set to:. Restrictive measures for control hydraulic system
28、pressure. When the hydraulic system pressure to achieve 10MPa, Lord top hydraulic console will alarm to meet limits maximum jacking force measures. Due to limited system pressure is lesser, when necessary, to ensure that guide pouring the concrete again under the condition of the suffers bump, dont move, changeless form. Guide installation the allowable deviation for: axis position: 3mm, top surface elevation: 0 + 3mm, two tracks from: 2mm so hydraulic system failure will greatly decrease, the reliability of pipe jacking also increase.
