LOAD TRANSFER FROM PILE TO SOIL - i-astm.com · PDF fileload transfer from pile to soil p ......
Transcript of LOAD TRANSFER FROM PILE TO SOIL - i-astm.com · PDF fileload transfer from pile to soil p ......
LOAD TRANSFER FROM PILE TO SOIL
P
SOFT SOIL LAYER Q = SKIN FRICTIONr
HARD SOIL LAYERQ END BEARINGQ = END BEARINGb
LOAD TRANSFER FROM PILE TO SOIL
P
SOFT SOIL LAYER Q = SKIN FRICTIONr
HARD SOIL LAYERQ END BEARINGQ = END BEARINGb
MECHANCAL PROPERTIES TEST‐ LOAD TEST ‐ STATIC METHOD‐ DYNAMIC METHOD
PHYSICAL PROPERTIES TESTINTEGRITY TEST(SEISMIC TEST)‐ INTEGRITY TEST(SEISMIC TEST)‐ SONIC CORING TEST
OBJECT OF PILE LOAD TEST
→ TO ENSURE THAT FAILURE DOES NOTOCCUR BEFORE THE DESIGN LOAD (WORKING PILE)OCCUR BEFORE THE DESIGN LOAD (WORKING PILE)
→ TO DETERMINE THE ULTIMATE BEARING CAPACITY FOR THE DESIGN OF WORKING PILES.(PILOT PILE)
→ TO INDICATE STRUCTURAL SOUNDNESS OF THE PILE→ TO INDICATE STRUCTURAL SOUNDNESS OF THE PILE.
→ TO DETERMINE LOAD – SETTLEMENT BEHAVIOUR OFA PILE TO PREDICT GROUP SETTLEMENT ORA PILE TO PREDICT GROUP SETTLEMENT OR DIFFERENTIAL SETTLEMENT OF OTHER PILES.
COMPRESSION TEST PROCEDURE
MAINTAINED LOADING TESTMAINTAINED LOADING TEST
PROCEDURE
INCREASE THE LOAD IN STAGES UNTIL THE PROPOSED
WORKING LOAD IS REACHED AND THEN UNLOADWORKING LOAD IS REACHED AND THEN UNLOAD.
INCREMENT OF LOAD AT EACH STAGES WILL BE PERMITTED WHEN RATE OF SETTLEMENT IS LESS THAN 0.25 mm./hr.
APPLICATION
FOR WORKING PILE TEST TO DETERMINE PILE LOAD BEHAVIOUR IN THE REGION OF WORKING LOAD WITH FACTOR OF SAFETY .
TEST NEED NOT REQUIRE TO DAMAGE THE PILE.
COMPRESSION TEST PROCEDURE
CONSTANT RATE OF PENETRATION TEST (CRP TEST)CONSTANT RATE OF PENETRATION TEST (CRP TEST)
PROCEDURE
LOAD WILL BE INCREASE BY MAINTAING RATE OF SETTLEMENT (CONSTANTLOAD WILL BE INCREASE BY MAINTAING RATE OF SETTLEMENT (CONSTANT SPEED) ABOUT THE SAME AS UNDRAINED TEST IN LABORATORY . (0.25‐1.25 MM./MIN.FOR COHESIVE SOIL OR 0.75‐2.50 MM./MIN. FOR COHESIONLESS SOIL.)
APPLICATION
TO DETERMINE ULTIMATE LOAD OF THE PILE. PILE CAN BE DAMAGED.
PILOT PILE IS RECOMMENDEDPILOT PILE IS RECOMMENDED.
COMPRESSION TEST SYSTEM
USING KENTLEDGE SYSTEM (DEAD LOAD)LOAD LESS THAN 500 TONS‐ LOAD LESS THAN 500 TONS
‐ NO ANCHORAGE AVILABLE OR POSSIBLE FOR ARRANGEMENT
‐ USE CONCRETE BOX, STEEL OR SAND AS DEAD LOAD.,
TEST WEIGHTS
WEDGESDIAL GAGES TEST BEAMS
REFERENCE BEAM
CROSS BEAMS
CRIBBING
CONCRETE PILE CAP
COMPRESSION TEST SYSTEMCOMPRESSION TEST SYSTEM
TEST BEAMS
STEEL PLATE
HYDRAULICJACK
TEST PLATEDIAL GAGES
REFERENCEBEAM
ANCHOR PILETEST PILE
TEST RESULT PRESENTATIONTEST RESULT PRESENTATION
LOAD V.S. SETTLEMENT PLOT
TIME V.S. SETTLEMENT PLOT
TIME V.S. LOAD PLOT
LOAD – SETTLEMENT – TIME RELATIONSHIPS OF 0.8 m DIA. X 50 m BORED PILEBORED PILE
LOAD- SETTLEMENT CURVELOAD , Tons
0 100 200 300 400 500 600 700 800 900 10000.0
TIME - SETTLEMENT CURVETIME , hrs
0 20 40 60 80 100 120
CYCLE 1
-5.0
CYCLE 1
CYCLE 2
EMEN
T , m
m
0.0
-5.0
-10.0
CYCLE 2
NT
, mm -10.0
CYCLE 3SETT
LE -15.0
-20.0
-25.0
CYCLE 3
SETT
LEM
EN
-10.0
TIME - LOAD CURVE
ons CYCLE 2
CYCLE 3800
700
600
500CYCLE 3
-20.0
21 99
LOA
D ,
To
CYCLE 1
400
300
200
100
0
-25.0
-21.99 0 20 40 60 80 100 120
TIME , hrs
ULITIMATE LOAD OF PILE
LOAD AT WHICH SETTLEMENT REACH 10% OF PILE DIAMETER
ULITIMATE LOAD OF PILE
- LOAD AT WHICH SETTLEMENT REACH 10% OF PILE DIAMETER (BEARING PILE)
- LOAD AT WHICH PILE CAN NOT TAKE ANY MORE LOAD FRICTION PILE (FRICTION PILE)
L O A D
T
QUL O A D
E N
T QU
T L
E M
E N
T
S E
T T
L E
M
S E
T
FRICTION PILE
S
BEARING PILE10 % Ø
- IN GENERAL, STRUCTURAL BUILDING ARE NOT PREMITTED FOR SETTLEMENT GREATER THAN 25 MM. FOR SIMPLEFOR SETTLEMENT GREATER THAN 25 MM. FOR SIMPLE BEAM DESIGN
Compare Davisson and Chin Method
CHIN' S METHODSETTLEMENT / LOAD, mm/Ton00 50 100 150 200 250 300
P = 174 Tons
DAVISSON ' S METHOD LOAD, Tons
00 0.02 0.04 0.06 0.08 0.10 0.12
-5
0.14
-5CYCLE 2
P = 174 Tons.ult
-10
ENT
,mm
-10
T ,m
m
-15
-20 y = -205.21x + 2.0403 P = 205 Tons
SETT
LEM
Eult
-15
-20 Davisson' s Criteria3 81+8 331+2d+PL/AE i
CHIN' S
SETT
LEM
ENT
-25
30
-25 AssumptionsE = 631 t / cm²
= 3.81+8.331+2d+PL/AE, in mmwhere d is pile size in m.
-30
-30