1drainage methods gvrs.ppt
DESCRIPTION
Drainage MethodsTRANSCRIPT
DRAINAGE METHODS
Dr. G. V. RAMA SUBBARAOConsulting Geotechnical Engineer
& ASSOCIATE PROFESSOR OF CIVIL
ENGINEERING S.R.K. INSTITUTE OF TECHNOLOGY,
ENIKEPADU, VIJAYAWADA – 521 108E-Mail: [email protected]
DRAINAGE METHODS
I. DEWATERING
II. DRAINS
CONSTRUCTION DEWATERING:
Temporary lowering of groundwater levels by pumping from wells or sumps to provide stable conditions for excavations below the natural groundwater level
METHODS OF DEWATERING SYSTEMS
METHODS OF DEWATERING SYSTEMS
Open Ditches and SumpsWell point Systems
Single-stage well point systemMulti-stage well point system
Deep Well DrainageVacuum DewateringElectro-Osmosis
DEWATERING through
Open Ditches and Sumps
Sump Pit / Rim Ditch
Well point Systems
WELL POINT
Figure. Self-jetting wellpoint.
WELL POINT DEWATERING SYSTEMS
Deepwells
Deep well point Drainage
Vacuum-air InjectionDewatering Method
Vacuum Well point System
Electro-osmotic Consolidation
Dewatering by Electro-Osmosis
Example applications: Dewatering water from a ground when excavations below ground water level are needed Dewatering construction excavations Lowering of ground water level
Other applications of wellpoint system: Dewatering in agriculture To gain water for house, garden and irrigations
Main applications of wellpoint systems
Wellpoint (1") Wellpoint (2")
Suction header pipe from Aluminium and Poliethylene
Jetting wellpoints into the groundThe typical sequence of operations when
installing wellpoints is as follows:
•connect jetting pipe to water jetting pump or hydrant, using jetting hose •if you are setting the wellpoint manually, position the jetting pipe vertically with its edge on a support (e.g. piece of thick board), next to the predetermined wellpoint setting location •when you set the wellpoint with jetting pipe using a crane, keep the pipe on the crane rope 150-200 mm above the wellpoint setting location •activate water jetting pump or open the hydrant •when water flows out of the jetting pipe, remove it from the support and lower it to the ground
Jetting wellpoints into the ground
Jetting assortment:[1] Jetting pipe D51, [2] Jetting pipe D133, [3] Jetting hose, [4] Jetting hose arc
Dewatering examples - photo
Installing wellpoints into the ground
Fig. Progressive system of installation of well points (for trenches)
Fig. Ring system of installation of well points (for Excavations)
WELL HYDRAULICS
II. DRAINS
Recommended CollectorPipe Configuration
