chapter 3 grouting grouting may be used in the following applications: 1.filling voids to prevent...
TRANSCRIPT
CHAPTER 3CHAPTER 3GROUTINGGROUTING
GROUTING MAY BE USED IN THE FOLLOWING GROUTING MAY BE USED IN THE FOLLOWING APPLICATIONS:APPLICATIONS:
1.1. FILLING VOIDS TO PREVENT EXCESSIVE SETTLEMENTFILLING VOIDS TO PREVENT EXCESSIVE SETTLEMENT2.2. TO INCREASE ALLOWABLE PRESSURE OF THE SOIL BOTH TO INCREASE ALLOWABLE PRESSURE OF THE SOIL BOTH
FOR NEW STRUCTURES AND / OR ADDITIONS TO EXISTING FOR NEW STRUCTURES AND / OR ADDITIONS TO EXISTING STRUCTURES.STRUCTURES.
3.3. CONTROL OF GROUNDWATER FLOWCONTROL OF GROUNDWATER FLOW4.4. PREVENTION OF LOOSE - LOOSE TO MEDIUM SAND PREVENTION OF LOOSE - LOOSE TO MEDIUM SAND
DENSIFICATION UNDER ADJACENT STRUCTURES (I.E. DENSIFICATION UNDER ADJACENT STRUCTURES (I.E. BOTH FOR VERTICAL AND LATERAL MOVEMENTS) DUE TO BOTH FOR VERTICAL AND LATERAL MOVEMENTS) DUE TO ADJACENT EXCAVATIONS, PILE DRIVING ETC.ADJACENT EXCAVATIONS, PILE DRIVING ETC.
5.5. GROUND MOVEMENT CONTROL DURING TUNNELING GROUND MOVEMENT CONTROL DURING TUNNELING OPERATIONSOPERATIONS
6.6. SOIL STRENGTHENING TO REDUCE LATERAL SUPPORT SOIL STRENGTHENING TO REDUCE LATERAL SUPPORT REQUIREMENTREQUIREMENT
7.7. SOIL STRENGTHENING TO INCREASE LATERAL AND SOIL STRENGTHENING TO INCREASE LATERAL AND VERTICAL RESISTANCE OF PILES.VERTICAL RESISTANCE OF PILES.
8.8. STABILIZATION OF LOOSE SANDS AGAINST STABILIZATION OF LOOSE SANDS AGAINST LIQUEFACTIONLIQUEFACTION
9.9. FOUNDATION UNDERPINNINGFOUNDATION UNDERPINNING10.10. SLOPE STABILISATIONSLOPE STABILISATION11.11. VOLUME CHANGE CONTROL OF EXPANSIVE SOILS VOLUME CHANGE CONTROL OF EXPANSIVE SOILS
THROUGH PRESSURE INJECTION OF LIME SLURRY (ONLY THROUGH PRESSURE INJECTION OF LIME SLURRY (ONLY FOR SOME EXPANSIVE SOILS NOT ALL)FOR SOME EXPANSIVE SOILS NOT ALL)
THREE WAYS OF INTRODUCING GROUT MATERIAL INTO THETHREE WAYS OF INTRODUCING GROUT MATERIAL INTO THESOIL ARE POSSIBLE:SOIL ARE POSSIBLE:
A.A. PERMEATION GROUTING :GROUT FILLS THE SOIL PORES. PERMEATION GROUTING :GROUT FILLS THE SOIL PORES. ESSENTIALLY NO CHANGE IN THE VOLUME OR ESSENTIALLY NO CHANGE IN THE VOLUME OR STRUCTURE OF THE ORIGINAL GROUND.STRUCTURE OF THE ORIGINAL GROUND.
B.B. DISPLACEMENT OR COMPACTION GROUNTINGDISPLACEMENT OR COMPACTION GROUNTINGC.C. HYDRAULIC FRACTURE OR ENCAPSULATION OR SQUEEZE HYDRAULIC FRACTURE OR ENCAPSULATION OR SQUEEZE
GROUTINGGROUTING
GROUTSGROUTS
DISPLACEMENT OR COMPACTION GROUTS : STIFF, LOW SLUMP (0-5 CM) MIXTURES OF CEMENT, SOIL, AND / OR CLAY AND WATER LIME SLURRIES ARE MOST COMMONLY USED IN ENCAPSULATION GROUTING
IN WATER / CEMENT GROUTS w/c= 0.5/1 – 6/1 HAVE BEEN USED.IF 0.5/1 RATIO IS USED STRENGTH WILL BE HIGHER BUT IT WILL BE HARDER TO INJECT. SEGREGATION AND FILTERING WILL BE LESS. CHEMICALS (LIKE CALCIUM LIGNOSULFONATE) ARE ADDED TO CONTROL FLUIDITY AND PENETRATION AND SETTING TIME (30 sec -- VERY LONG) AND PLASTISIZERS TO PREVENT FLOCCULATION.
IN SOIL / CEMENT GROUTS, VOLUMES OF SOIL 4-6 TIMES THE IN SOIL / CEMENT GROUTS, VOLUMES OF SOIL 4-6 TIMES THE
VOLUME OF CEMENT ARE MOST COMMON ALTHOUGH RATIOS VOLUME OF CEMENT ARE MOST COMMON ALTHOUGH RATIOS
FROM 1 TO 12 HAVE BEEN USED.FROM 1 TO 12 HAVE BEEN USED.
VOLUME OF THE MIXING WATER VARIES FROM ABOUT 3/4 - 2 VOLUME OF THE MIXING WATER VARIES FROM ABOUT 3/4 - 2
TIMES THE VOLUME OF CLAY PER BAG CEMENT IN CEMENT-TIMES THE VOLUME OF CLAY PER BAG CEMENT IN CEMENT-
CLAY GROUTS.CLAY GROUTS.
VOLUME OF THE MIXING WATER VARIES FROM 1/3-1 TIMES VOLUME OF THE MIXING WATER VARIES FROM 1/3-1 TIMES
THE LOOSE VOLUME OF SAND PER BAG OF CEMENT IN THE LOOSE VOLUME OF SAND PER BAG OF CEMENT IN
CEMENT - SAND GROUTSCEMENT - SAND GROUTS
GENERALLY MINIMUM WATER CONTENT WHICH WILL STILL GENERALLY MINIMUM WATER CONTENT WHICH WILL STILL
YIELD AN INJECTABLE UNXIUIE IS USED.YIELD AN INJECTABLE UNXIUIE IS USED.
SULFATES AND SULFATE BEARING GROUND WATER ARE THE SULFATES AND SULFATE BEARING GROUND WATER ARE THE
ENEMY OF CEMENT.ENEMY OF CEMENT.
PARTICULATE GROUTS CANNOT BE INJECTED AS PARTICULATE GROUTS CANNOT BE INJECTED AS
PERMEATION GROUTS INTO SOILS FINER THAN MEDIUM TO PERMEATION GROUTS INTO SOILS FINER THAN MEDIUM TO
COARSE SANDS. THIS APPROXIMATELY CORRESPONDS TO A COARSE SANDS. THIS APPROXIMATELY CORRESPONDS TO A
PERMEABILITY OF ABOUT 5x10-4 cm/sec.PERMEABILITY OF ABOUT 5x10-4 cm/sec.
AREAS OF USE :AREAS OF USE :
CEMENT GROUTSCEMENT GROUTS : FOR BOTH : FOR BOTH IMPERMEABILISATION AND STRENGTH INCREASEIMPERMEABILISATION AND STRENGTH INCREASE
SOIL, CLAY AND CHEMICAL GROUTSSOIL, CLAY AND CHEMICAL GROUTS : : IMPERMEABILISATION AND COMPACTION IMPERMEABILISATION AND COMPACTION GROUTINGGROUTING
CLAY GROUTSCLAY GROUTS : LIMITED USE (USUALLY FILLING : LIMITED USE (USUALLY FILLING VOIDS ETC)VOIDS ETC)
CLAY-CEMENT GROUTSCLAY-CEMENT GROUTS : FILLING VOIDS, : FILLING VOIDS, MUDJACKINGMUDJACKING
TYPES I AND II PORTLAND CEMENT ARE SUITABLE FOR SOILS TYPES I AND II PORTLAND CEMENT ARE SUITABLE FOR SOILS
COARSER THAN 0.60 mm.COARSER THAN 0.60 mm.
TYPE III PORTLAND CEMENT IS SUITABLE FOR SOILS COARSER TYPE III PORTLAND CEMENT IS SUITABLE FOR SOILS COARSER
THAN 0.42 mm. (BENTONITE: 0.25 mm)THAN 0.42 mm. (BENTONITE: 0.25 mm)
ACCORDING TO CARON, PARTICLES 50 micron SIZE CAN BE ACCORDING TO CARON, PARTICLES 50 micron SIZE CAN BE
INJECTED TO COARSE SAND (> 0.8 mm). COLLOIDAL INJECTED TO COARSE SAND (> 0.8 mm). COLLOIDAL
SUSPENSIONS CAN BE INJECTED INTO MEDIUM SAND ( 0.1 TO 0.8 SUSPENSIONS CAN BE INJECTED INTO MEDIUM SAND ( 0.1 TO 0.8
mm). FINE SANDS & SILTS REQUIRE NEWTONIAN SOLUTIONS OF mm). FINE SANDS & SILTS REQUIRE NEWTONIAN SOLUTIONS OF
LOW VISCOSITY.LOW VISCOSITY.
THE ABILITY OF PARTICULATE GROUTS TO PENETRATE A THE ABILITY OF PARTICULATE GROUTS TO PENETRATE A
FORMATION IS OFTEN INDICATED IN TERMS OF A GROUTABILITY FORMATION IS OFTEN INDICATED IN TERMS OF A GROUTABILITY
RATIO. SOME GROUTABILITY RATIOS THAT HAVE BEEN PROVEN RATIO. SOME GROUTABILITY RATIOS THAT HAVE BEEN PROVEN
USEFUL ARE GIVEN BELOW:USEFUL ARE GIVEN BELOW:
GROUTING CONSISTENTLY POSSIBLEGROUTING CONSISTENTLY POSSIBLE
GROUTING NOT POSSIBLEGROUTING NOT POSSIBLE
GROUTING CONSISTENTLY POSSIBLEGROUTING CONSISTENTLY POSSIBLE
GROUTING NOT POSSIBLEGROUTING NOT POSSIBLE
24)(
)(
85
15 grout
soil
D
DN
11
11)(
)(
95
10 grout
soilc D
DN
6
FOR ROCKS GROUTING POSSIBLE
NOT POSSIBLE
5)( 95
grout
R D
fissureofWidthN
2
SOILS CONTAINING < 10 % FINES ARE USUALLY SOILS CONTAINING < 10 % FINES ARE USUALLY PERMEATION GROUTED WITH CHEMICALS.PERMEATION GROUTED WITH CHEMICALS.
IF FINES CONTENT > 15 % EFFECTIVE CHEMICAL GROUTING IF FINES CONTENT > 15 % EFFECTIVE CHEMICAL GROUTING MAY BE DIFFICULT, FOR FINES CONTENT > 20 % MAY BE DIFFICULT, FOR FINES CONTENT > 20 % PERMEATION GROUTING WILL NOT BE POSSIBLE BUT PERMEATION GROUTING WILL NOT BE POSSIBLE BUT CHEMICAL GROUTS NOT BE DISTRIBUTED ALONG AND CHEMICAL GROUTS NOT BE DISTRIBUTED ALONG AND THROUGH HYDRAULIC FRACTURES.THROUGH HYDRAULIC FRACTURES.
Fig 3.3 Modulus of Deformation versus qu
USE OF HIGH POLYMERS IN JAPAN IS FORBIDDEN OFTEN USE OF HIGH POLYMERS IN JAPAN IS FORBIDDEN OFTEN
THE ACCIDENT IN 1974 AS A RESULT OF INJECTION OF THE ACCIDENT IN 1974 AS A RESULT OF INJECTION OF
ACRYLAMIDES (GROUNDWATER POLLUTION EVEN IN THE ACRYLAMIDES (GROUNDWATER POLLUTION EVEN IN THE
USE OF SILICATES PH VALUE OF GROUND WATER AROUND USE OF SILICATES PH VALUE OF GROUND WATER AROUND
INJECTION POINTS IS REQUIRED TO BE <8.6. THUS, NEW INJECTION POINTS IS REQUIRED TO BE <8.6. THUS, NEW
NON-ALKALINE SILICATE GROUTS HAVE BEEN DEVELOPED. NON-ALKALINE SILICATE GROUTS HAVE BEEN DEVELOPED.
THESE CONSIST OF SILICA - SOL SOLUTIONS WITH PH VALUE THESE CONSIST OF SILICA - SOL SOLUTIONS WITH PH VALUE
OF 1 TO 2.OF 1 TO 2.STRUCTURAL CHEMICAL GROUTING IS QUITE POPULAR.STRUCTURAL CHEMICAL GROUTING IS QUITE POPULAR.
Fig 3.4 Various Structural Grouting Applications
COMPACTION GROUTINGCOMPACTION GROUTING
THE FOLLOWING ARE IMPORTANT IN COMPACTION THE FOLLOWING ARE IMPORTANT IN COMPACTION
GROUTINGGROUTING
LAYOUT OF HOLES IN NUMBERLAYOUT OF HOLES IN NUMBER
LOCATION OF HOLES & INCLINATIONLOCATION OF HOLES & INCLINATION
DEPTHDEPTH
SEQUENCE OF HOLES GROUTED PROCEDURE OF SEQUENCE OF HOLES GROUTED PROCEDURE OF
GROUTING INDIVIDUAL HOLEGROUTING INDIVIDUAL HOLE
TYPICAL APPLICATION DETAILS ARE :TYPICAL APPLICATION DETAILS ARE :
MIN DISTANCE TO THE SURFACEMIN DISTANCE TO THE SURFACE
TRIANGULAR PATTERN USUALLY, 1.5 - 5 M SPACINGTRIANGULAR PATTERN USUALLY, 1.5 - 5 M SPACING
PRIMARY (~5 M) / SECONDARY HOLES, GROUT TAKESPRIMARY (~5 M) / SECONDARY HOLES, GROUT TAKES
HOLES UNDER FOUNDATIONS, RATHER THAN OPEN HOLES UNDER FOUNDATIONS, RATHER THAN OPEN
AREAS; PERIPHERAL HOLES FIRSTAREAS; PERIPHERAL HOLES FIRST
< # 200 % 10 - % 30, SAND IN COMPACTION GROUTING < # 200 % 10 - % 30, SAND IN COMPACTION GROUTING
100% PASSING NO.8 SIEVE, A COARSER SAND WILL 100% PASSING NO.8 SIEVE, A COARSER SAND WILL
CAUSE WATER TO BE DRIVEN OUT.CAUSE WATER TO BE DRIVEN OUT.
PORTLAND SAND, FINE SAND AND WATER % 12. CEMENT PORTLAND SAND, FINE SAND AND WATER % 12. CEMENT
$ 2800 KN/M2 GROUT$ 2800 KN/M2 GROUT
PRESSURES 0-4200 kN/mPRESSURES 0-4200 kN/m22
TWO BASIC METHODS FOR CONSTRUCTION:TWO BASIC METHODS FOR CONSTRUCTION:
1 . FROM TOP TO DOWN1 . FROM TOP TO DOWN
2. FROM UP TO BOTTOM2. FROM UP TO BOTTOM
GROUTING IS DONE IN STAGES, ONLY 0.75 - 1.0 m OF HOLE ISGROUTING IS DONE IN STAGES, ONLY 0.75 - 1.0 m OF HOLE IS
GROUTED AT A TIME.GROUTED AT A TIME.
PROCEDURE FOR GROUTING FROM TOP TO BOTTOMPROCEDURE FOR GROUTING FROM TOP TO BOTTOM
1.1. DRILL A HOLE TO THE TOP OF THE ZONE (MIN. 1.5 M)DRILL A HOLE TO THE TOP OF THE ZONE (MIN. 1.5 M)
2.2. INSERT A CASING IN THE HOLE AND FILL THE ANNULAR INSERT A CASING IN THE HOLE AND FILL THE ANNULAR
SPACE BETWEEN THE CASING AND THE HOLE WITH QUICK SPACE BETWEEN THE CASING AND THE HOLE WITH QUICK
SETTING CEMENT.SETTING CEMENT.
3.3. DRILL THROUGH TIE CASING AND ADVANCE THE HOLE 1-DRILL THROUGH TIE CASING AND ADVANCE THE HOLE 1-
2.5 m. NEVER EXCEED 3-3.5 METERS.2.5 m. NEVER EXCEED 3-3.5 METERS.
4.4. PUMP IN GROUT UNTIL THERE IS "REFUSAL" OR SLIGHT PUMP IN GROUT UNTIL THERE IS "REFUSAL" OR SLIGHT
MOVEMENT OF THE GROUND SURFACE.MOVEMENT OF THE GROUND SURFACE.
5.5. REPEAT THE PROCEDURE (ITEMS 3 AND, 4) AFTER REPEAT THE PROCEDURE (ITEMS 3 AND, 4) AFTER
HARDENING OF THE PREVIOUSLY PLACED GROUT UNTIL HARDENING OF THE PREVIOUSLY PLACED GROUT UNTIL
THE BOTTOM OF THE ZONE TO BE STABILIZED IS REACHED.THE BOTTOM OF THE ZONE TO BE STABILIZED IS REACHED.
PROCEDURE OF GROUTING FROM BOTTOM TO UP:PROCEDURE OF GROUTING FROM BOTTOM TO UP:
1.1. DRILL A HOLE TO THE BOTTOM OF THE ZONE TO BE DRILL A HOLE TO THE BOTTOM OF THE ZONE TO BE
STABILIZEDSTABILIZED
2.2. PLACE CASING TO WITHIN A METER OF THE BOTTOM OF PLACE CASING TO WITHIN A METER OF THE BOTTOM OF
THE HOLE.THE CASING SHOULD BE A SNUG FIT AND THE HOLE.THE CASING SHOULD BE A SNUG FIT AND
MAY REQUIRE PUSHING OR DRIVING INTO PLACE.MAY REQUIRE PUSHING OR DRIVING INTO PLACE.
SOMETIMES IT IS DRIVEN ENTIRELY (i.e. PREDRILIING SOMETIMES IT IS DRIVEN ENTIRELY (i.e. PREDRILIING
ELIMINATED)ELIMINATED)
3.3. PUMP IN THE GROUT UNTIL 'REFUSAL' IS ACHIEVED (OR PUMP IN THE GROUT UNTIL 'REFUSAL' IS ACHIEVED (OR
SLIGHT)SLIGHT)
4.4. RAISE THE CASINGRAISE THE CASING
5.5. PUMP AGAIN AND REPEAT 4 AND 5 UNTIL THE GROUND PUMP AGAIN AND REPEAT 4 AND 5 UNTIL THE GROUND
SURFACE IS REACHED.SURFACE IS REACHED.
TOP-DOWN METHOD IS MORE EXPENSIVE BUT THERE ARE TOP-DOWN METHOD IS MORE EXPENSIVE BUT THERE ARE
SUBSTANTIAL ADVANTAGES : GREATER TAKE OF GROUT SUBSTANTIAL ADVANTAGES : GREATER TAKE OF GROUT
PER HOLE AND MORE EFFECTIVE, HIGHER PRESSURES PER HOLE AND MORE EFFECTIVE, HIGHER PRESSURES
MAY BE USED WHEN GOING DEEPER. IN PROBLEM SOILS MAY BE USED WHEN GOING DEEPER. IN PROBLEM SOILS
EXTEND TO THE SURFACE FROM TOP TO DOWN IS EXTEND TO THE SURFACE FROM TOP TO DOWN IS
ESSENTIAL.ESSENTIAL.
PLOT 'TAKES' TO CONTROL THE RELATIVE SOIL PLOT 'TAKES' TO CONTROL THE RELATIVE SOIL
CONDITIONSCONDITIONS
CONTROL OF PUMPING RATE IS THE MOST IMPORTANT CONTROL OF PUMPING RATE IS THE MOST IMPORTANT
CONSIDERATION OF GROUTING TECHNIQUE. MAX. CONSIDERATION OF GROUTING TECHNIQUE. MAX.
PRESSURE DEVELOPED AND QUANTITY OF GROUT PRESSURE DEVELOPED AND QUANTITY OF GROUT
INJECTED DEPEND ON PUMPING RATEINJECTED DEPEND ON PUMPING RATE
RAPID PUMPING IS ECONOMICAL BUT IT CAUSES PRESSURE RAPID PUMPING IS ECONOMICAL BUT IT CAUSES PRESSURE
BUILD UP AND EARLY RAISING OR RUPTURE OF THE OVERLYING BUILD UP AND EARLY RAISING OR RUPTURE OF THE OVERLYING
SOIL. THEREFORE LIMIT THE GROUT QUANTITY INJECTED AND SOIL. THEREFORE LIMIT THE GROUT QUANTITY INJECTED AND
AMOUNT OF DENSIFICATION. THEREFORE APPROPRIATE AMOUNT OF DENSIFICATION. THEREFORE APPROPRIATE
PUMPING RATE IS BASICALLY DEPENDENT ON THE AMOUNT OF PUMPING RATE IS BASICALLY DEPENDENT ON THE AMOUNT OF
PRESSURE AND RATE OF PRESSURE BUILD UP WHICH ARE PRESSURE AND RATE OF PRESSURE BUILD UP WHICH ARE
INFLUENCED BY ;SOIL TYPE, DEGREE OF COMPACTION, INFLUENCED BY ;SOIL TYPE, DEGREE OF COMPACTION,
MOISTURE CONTENT,DEPTH OF INJECTION, CONFINING SOIL MOISTURE CONTENT,DEPTH OF INJECTION, CONFINING SOIL
AND STRUCTURAL PRESSURE.AND STRUCTURAL PRESSURE.
IN MOST MIXED SOILS BEGINNING RATE WILL BE ON THE ORDER IN MOST MIXED SOILS BEGINNING RATE WILL BE ON THE ORDER
OF 0.3 m3/min. 3 -5 m3/min IS APPLIED IN VERY LOOSE SOUS AND OF 0.3 m3/min. 3 -5 m3/min IS APPLIED IN VERY LOOSE SOUS AND
SOILS WITH LARGE VOIDS. 0.003 -0.014 m3/min IS USED IN SOILS WITH LARGE VOIDS. 0.003 -0.014 m3/min IS USED IN
UNDRAINED CLAYS AND HIGHLY PLASTIC CLAYS.UNDRAINED CLAYS AND HIGHLY PLASTIC CLAYS.
PRESSURES : 350 KPA - 1700 KPA WITHIN 1.5 - 2 M OF THE PRESSURES : 350 KPA - 1700 KPA WITHIN 1.5 - 2 M OF THE
SURFACE AND UP TO 3500 kPa OR MORE WHEN D > 6 M, SELDOM SURFACE AND UP TO 3500 kPa OR MORE WHEN D > 6 M, SELDOM
> 4200 kPa EXCEPT OPEN THE TIGHT HOLE (7000 kPa).> 4200 kPa EXCEPT OPEN THE TIGHT HOLE (7000 kPa).
COMPARISON BETWEEN JET GROUTING METHODS
CCP JSG CJG SSS-MAN
GROUTINGPRESSURE(MPa)
20 20 40 20-70
TYPE OF SUSPENSION
CEMENT WATER
AIR PROTECTCEMENT-WAT.
AIR PROTECTWATER
AIR. WATERMIXTURE
TYPE JET JET SEMI-DISP.FULL
DISPLACEMENT
DIAMETER OF(mm)
1.2 3-3.2 1.8-2.3 2.O-2.8
VELOCITY(r/s) 0.33 0.10 0.08 0.05-0.12
DIAMETER OFCOLUMN (m)
0.8 2.0 3.0 3.5
SOIL EXC.GRAVEL ALL EXC. GRAVEL ALL