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FIELD GEOTECHNICAL TESTS. Main Points of Presentation. plate load tests ( determination of deformability of soils and compaction rate identification) dynamic penetration tests (confirmation of bedrock, cavity localization, deduction of mechanical parametres of soils)
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Main Points of Presentation • plate load tests (determination of deformability of soils and compaction rate identification) • dynamic penetration tests (confirmation of bedrock, cavity localization, deduction of mechanical parametres of soils) • borehole tests of deformation properties (determination of deformabilityorstrenght parametres of soils and rocks) – presiometer Menard, uniaxial jack Goodman • tests of pile integrity (by ultrasound measurement or by method SIT - Sonic Integrity Testing) • supervision and evaluation of results of pile dynamic tests by method PDA • inspection of borehole and audiovizual record form TV probe
Method DP is possible to use for: Dynamic penetration tests • determination of soil compaction or consistency • determination of boundary between surface deposits and bedrock • determination of boundary between different ground bearing capacity and determination of soil layer thickness • landfill and backfill degree compaction control • determination of slip plane position and shape on slides • searching and checking of voids and caverns • approximate determination of the modulus of deformation Edef • river bed, lake bed and water reservoir bed sounding for determination of alluvium thickness • complementation of borehole investigation
Dynamic Penetration Tests Heavy dynamic penetration aparature - Prague 5 Zličín, 2003 Producer: UNIGEO a.s Weight of the driving rig: 50 kg Height of fall of the driving rig : 0,5 m Diameter of the tip: 43,7 mm Cross section area of the tip: 15 cm2
Medium dynamic penetration aparature - Hradec Králové 2003 Producer: RMS (SRN) Weight of the driving rig: 30 kg Height of fall of the driving rig: 0,5 m Diameter of the tip: 43,7 (35,7)mm Cross section area of the tip: 15 (10) cm2
Dynamic Penetration Tests Medium dynamic penetration aparature - Prague Trója 2003
Dynamic Penetration Tests Example of the profile derived from dynamic penetration
Presiometer applications in geotechnics: Borehole Tests of Deformation Properties • determination of elastic deformation characteristic (presiometric modulus of deformation Ep def) • determination of radial pressure limit plim – limit state of failure of a soil in consequence of shearing strength accomplishment It is possible to determine by presiometer: • development of elactic-deformation and strength properties with the depth • rock anizotropy • reducing of concentration zone around underground building stope • result and quality control of rock grouting
control and measuring board source of compressed-air connecting coaxial cable Presiometr Menard – type GA Borehole Tests of Deformation Properties Producer: Louis Ménard (France) Maximum attainable depth: cca 60 m Maximum pressure: 2,4 MPa Probe diametres:44 mm, 60 mm, 74 mm measuring probe
Borehole Tests of Deformation Properties Presiometric tests inside boreholes – trial gallery Valík 2002
Borehole Tests of Deformation Properties Ouput from presiometric test in rock – gallery Panenská 2002
plim = 1,23 MPa Compact clay 800 30 25 600 ] Ep = 8,5 MPa 20 ] 3 3 [cm [cm V 400 15 60-30 objem V objem 10 200 5 0 0 0,00 0,20 0,40 0,60 0,80 1,00 1,20 tlak na stěnu vrtu p [MPa] Borehole Tests of Deformation Properties Ouput from presiometric test in soil– Brno 2002
Hydraulic press Borehole Tests of Deformation Properties Uniaxial press Goodman Borehole Tests of Deformation Properties Producer: SINCO (USA) Maximum attainable depth : cca 30 m Maximum pressure : 12 MPa Probe diameter: 74 mm Subtraction unit probe with sensor of displacement
Ep,2 = 1711 MPa Sandstone 1,2 1,0 ] 0,8 [mm s Edef,2 = 1442 MPa 0,6 deformace 0,4 Edef,1 = 729 MPa 0,2 0,0 0,0 2,0 4,0 6,0 8,0 10,0 tlak na stěnu vrtu p [MPa] Borehole Tests of Deformation Properties Output from unaxial press Goodman test – quarry Střeleč 2000
receiver sender Test of Pile Integrity Test of pile integrity using ultrasound method: principle Producer: PUNDIT (Great Britain) Maximum attainable depth : 50 m Probe diameter : 34mm
Strong anomaly Test of Pile Integrity Ouput from the test of pile integrity using ultrasound method – Strážný 1999
Output from the test of pile integrity using method SIT – bridge Myšenec 2003
Dynamic pile tests by method PDA (Pile Driving Analysis): Supervision and Evaluation of Results of Pile Dynamic Tests by PDA Method • by company: DUBA Testing s.r.o. • principle: measuring of mechanical waves in pile body induced by free falling hammer, specifications: weight of hammer 8 or 16 t, selected height of free fall and time slope measuring of relative deformation (deformetres) and oscillation velocity of pile head (accelerometer) • output is determination of pile load capacity and pile settling • test by PDA method proceed especially on bridge construction on trial and final piles • main activities of workgroup 034 are output evaluation and final report compilation with piles diameter and length recommendation
Instalation of 16 t hammer – Písek – MÚK Doběšice 2003 Pile Dynamic Tests
Preparation of the hammer and detail of senzor instalation, highway D5 – SO 207 2002 Pile Dynamic Tests
Evaluation of PDA test in situ - highway D5 – SO 207, 2002 Pile Dynamic Tests
Borehole TV probe Inspection of Borehole and Audiovizual Record from TV Probe Producer: Výpočetní technika Most a.s. Maximum depth: 30 m Probe diameter: 40 mm