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Prestressing tendons are the backbone of the structure. When properly stressed, they will prevent the structure from cracking and deteriorating. But,a badly stressed tendon looks exactly like a properly stressed tendon. Therefore, the only way to ensure proper stressing is to have an experienced, trained crew (Appendix B) and an inspector present during all stressing operations.

Stressing should be considered a basically unsafe operation. People operating the equipment and taking measurements should never stand behind a live jack. This is also true at the dead-end of the strand: never stand behind the anchor of a tendon being stressed. Although it does not happen often, tendons do break, wedges do let go and large forces are released in a split second, making jacks jump and propelling tendons out of an anchorage. In order to make everybody on the project aware of the fact that there is a tendon being stressed, a warning system should be in place such as flashing lights or red flags.

3.8.2 Jacking Force

The force required in each tendon is determined by the Designer and is given on the approved shop drawings or job stressing manual. Also, the corresponding elongations are pre-determined taking into account all losses due to curvature friction, wobble, wedge set, and friction within the anchor and jack, as necessary. For post-tensioning, measurement of elongations serves as a check of the anticipated jacking force primarily given by the gauge pressure and calibration chart.

The stressing operation should constantly be monitored by an inspector. There are two basic pieces of information that need to be recorded: tendon elongations and gauge pressures. Both will give an indication whether the tendon is stressed to the force required. The gauge pressure is a direct measurement of the force at the jack and the elongation will give an indication how the remainder of the tendon is being stressed. Normally the tendon will be stressed to a predetermined gauge pressure, representing a certain force in the tendon at the stressing end. The elongation measured at this point is compared to the theoretically determined elongation.

3.8.3 Measuring Elongations on Strand Tendons

When stressing a tendon a certain portion of jack extension will be needed to remove the slack. This gives a false initial elongation that should not be part of the real elongation measurements. For this reason, the first step is to stress the tendon an initial force of approximately 20% of the final force to remove the slack. From this point up to 100% of the required load, the extension of the jack will cause pure elongations of the tendon. At the end of the operation, a correction can be made for the unmeasured portion of the elongation by straight extrapolation.

The accuracy of the determination of the elongation obtained during the first step, i.e. tensioning up to 20% of the jacking force, can sometimes be improved by recording elongations at intermediate gauge readings of 40%, 60% and 80% and plotting results on a graph. Ideally, the graph should be a straight line.

Intermediate elongations must be recorded if a long tendon has to be stressed using two or more pulls on the jack when the required elongation is greater then the available stroke.

For short, mono or multi-strand tendons it may suffice to check the elongation for the stressing range between 20% and 100% load against the calculated value for this range. Short tendons are those generally less than about 30M (100 feet) long where the expected elongation is only about 0.2M (8 inches) or less and is easily made with a single, steady and continuous stroke of the jack. Short tendons include, for example, transverse tendons in deck slabs.

Elongation may be measured by the extension of the cylinder beyond the barrel of the jack. However, this is acceptable only if the wedge pull-in of the internal wedges that grip the strand inside the jack is reliably known; it is deducted from the measured extension on the cylinder to give the actual strand elongation. This method is often preferred for convenience.

Alternatively, measurement of elongations may be made to a point directly by adding an attachment to one of the strand tails and measuring between the tip of the attachment and the (immovable) barrel of the jack. In fact, the difference between this measurement and that solely of the cylinder extension is the pull-in of the internal jack wedges.

Alternatively, elongation can be measured directly from the face of the concrete to a mark on the strand tails. At least two randomly selected strands are marked. The mark can be a scribed mark or saw cut on the strand tail beyond the back of the jack or it can be made with tape or spray paint and pencil. The mark is placed after 20% of the jacking force has been applied. The distance of the mark to a fixed point on the concrete face or on the immovable barrel of the jack is recorded. As the jack is pumped out, this distance increases. Elongation measurements are made only on one of the marked strands. The other marked strand is there just in case the strand being measured should slip.

With any multi-strand stressing operation, it is good practice to mark several strand tails (at 20% load) at the same location using spray paint and pencil or tape to give a visible assurance that the strands are elongating by the same amount; any slip is easily noticed.

When stressing reaches full load, providing that the elongation is within the required tolerance of that anticipated, the jack is released and the tendon is anchored off by the permanent wedges. Wedge pull-in must be recorded and deducted from the elongation at full load to give the final actual elongation at this end of the tendon.

For small cross section members, such as I-girders, proper account should be taken to compensate for elastic shortening of the concrete when measuring elongations.

3.8.4 Measuring Elongations on PT Bars

Temporary bar tendons for erection purposes are usually short (i.e. from about 3 to 6M (10 to 20 ft) long). Elongations are small and are not usually measured for temporary applications; bars are jacked to load given by jacks pressure gauge.

For permanent PT bars, elongations should be checked as secondary verification of force. The elongation should be measured from a fixed point on the face of the concrete to a mark on the bar beyond the end of the jack. The slack, as in couplers, should be removed by applying 20% of the load. The elongation for the range between 20% and 100% required load should be checked against that calculated for this range.

For small cross section members, such as I-girders, proper account should be taken to compensate for elastic shortening of the concrete when measuring elongations.

3.8.5 Field Variables

Friction between the strands and ducts and within anchors and jacks reduces the effective force in the tendon. The main sources of friction are:

• 
  Friction between the tendon and duct due to curvature of the tendon profile("mq").
  
• 
  Friction between the tendon and duct due to unanticipated wobble ("kl").
  
• 
  Friction in the anchorage as strands flare to pass through the wedge-plate (%).
  
• 
  Friction within the jack itself. (This may be given as a percentage (%) by the post-tensioning supplier or it may be eliminated by use of a calibration curve of gauge pressure verses delivered jacking force).
  

3.8.5.2 Anchor Set or Wedge Set

When a strand tendon has been jacked to the required force and the jack is released, the wedges are drawn into the wedge plate until they bite and secure the strand. Typically the amount of wedge set or "draw-in" is about 10mm (3/8in) (Figure 3.33).

Figure 3.33 - Anchor Set or Wedge Set

Wedge set is measured in the field using the same reference marks on the strands as used for elongations. It is the difference between the elongation before and after release of the jack.

3.8.5.3 Strand Slip

Occasionally during stressing strands may slip at the wedges. This might happen if the size of the strands and wedges are at opposite ends of their manufactured tolerance range.

When stressing the crew and inspector should make sure that no strands slip. All strands in the tendon should be marked at both ends so that a slipped strand will show up immediately. One way to do this is to cut the strands off evenly at both ends after the jack has been attached and pressurized. The cut should be made at some distance from a dead end wedge plate and beyond the rear of the stressing jack(s) leaving a sufficient length projecting in case it is necessary to re-grip and re-stress. Another method is to mark all strands with spray paint. A slipped strand will show up promptly by lagging behind the other strands. (It is not possible, nor is it necessary except in very unusual circumstances, to identify which strand is which at both ends of the tendon).

3.8.5.4 Re-Gripping of Strand by Wedges

In multi-stage stressing of a long tendon that requires re-gripping, it is important to makes sure that intermediate re-gripping does not take place at a location that has already been gripped by wedges - or else slip or breakage could occur.

3.8.6 Final Force

The final force in the tendon is the jacking force minus all effects due to various losses described above. If after release of the jack, there is some doubt about the adequacy of the force a "lift-off" test may be necessary (see 3.8.8).

In the field, during stressing operations, it is only possible to monitor the jacking force given by the gauge pressure and calibration chart and to measure the elongation and wedge seating. These are the essential observations needed to ensure that the tendon has the required final force. They should be properly recorded in a stressing report. An example of a Stressing Report is given in Tables 3.3 (a) and (b).

Tendon force is primarily determined by the jack gauge pressure and calibration chart. Measured elongations are a secondary check of tendon force and should agree within 5% of calculated values for tendons over 15M (50 feet) long or 7% for tendons less than this (AASHTO LRFD Construction Specifications 10.10.1.4). Some project specifications may have different percentages for agreement for both long and short tendons.

3.8.7 Strand End Cut-Off

The ends of the strands should only be cut off if the jacking forces and elongations are satisfactory. If there is any doubt that might require verification by a lift-off test or additional jacking, strands should not be cut. Preferably, strands should be trimmed as soon as possible, so that permanent grout caps can be placed over the wedge plate to seal the tendon until grouting.

Strands should be cut off at the wedges leaving approximately 12 to 20mm (½" to ¾") of strand projecting but no greater than that which can be accommodated by any permanent non-metallic grout cap supplied for installation with the post-tensioning system. Strands should be cut only with an abrasive cutting tool. Under no circumstances should flame cutting be used as the heat can soften the strands and wedges and lead to loss of strands. Recently, plasma cutters have become available; their use should only be with strict inspection and approval of the Engineer.

After strand tails have been cut-off, the ends of the tendon should be temporarily protected in an approved manner until the tendon has been grouted. Preferably, a non-metallic (plastic) grout cap should be placed over the strands and wedges.

3.8.8 Lift-Off

Occasionally, after release of the jacking force, if there is some doubt of the adequacy of the force a "lift-off" test may be necessary. The jack remains in place or is re-installed and gradually taken up to load. The strands are marked and the position of the mark from the face of the anchor plate is measured very carefully. If this mark is beyond the end of the jack, then as the jack load increases, it will move only by the amount of elongation on that part of the strand passing though the jack. Since this is very little amount it may be immeasurable.

When the load reaches and passes that in the tendon, the tendon itself begins to elongate over its full length (less the effects of friction). This elongation should be noticeable by measuring the marks. The gauge should begin to register a higher pressure than that at which the tendon was first released. Also at this point, the wedges should begin to move from the wedge plate. This is the point of "lift-off" and should verify the force in the tendon at the jack.

A caution: if the load is significantly low then jacking to the required load may proceed providing that the previous point of the wedge grips is elongated clear past the wedges so they bite onto fresh strand. If not, there is a risk that the wedges may not properly re-grip. Hence, lift-off tests should be performed only when necessary and not as a matter of routine.

3.9 Stressing Records

All information relating to the stressing of a tendon should be recorded. The stressing reports are very important. They will be invaluable when problems occur during the stressing operation.

The following information should be included in the report:

• 
  Tendon identification e.g. tendon number, girder/web number, span/unit number.
  
• 
  Date and time when the tendon was stressed.
  
• 
  Information on the strand used to make the tendon - such as the coil pack and heat number for the strands.
  
• 
  The jack and gauge identification numbers.
  
• 
  The required elongation and jack force or gauge pressure.
  
• 
  The anchor set at the live end as well as at the dead end.
  
• 
  The stressing end(s) for the tendon.
  
• 
  The pressure gauge readings at which elongation measurements are made. Important are the initial and the final readings -intermediate readings should be carefully noted.
  
• 
  Any comments about events that occurred during stressing operation - such as wire breakages, slipped strands, popping noises etc.
  
• 
  The name of the inspector and the stressing crew foreman.
  

3.10 Stressing Problems and Solutions

3.10.1 Strand Slip

Slip of a strand can occur during the stressing operation and while anchoring the tendon. The reason is normally a defective wedge. This may be caused by a rusty surface on the outside of the wedge or the inside of the chuck, preventing the wedge from having a firm grip on the strand. Worn out teeth on the wedges inside the jack can also be a reason. In most cases, slip can be prevented by using properly maintained chucks and wedges.

Slip during stressing should reveal itself at marks made on the strand tails for this purpose. If slip is significant, (say, more than about an inch) it should be taken into account when stressing the remainder of the tendon. The slipped strands are under a lower stress. This will result in a lower overall force in the tendon for the required elongation. However, in order not to overstress other strands that do not slip, the target gauge pressure should be reduced in proportion to the number of slipped strands and amount of slip on each.

For example, if one strand out of 12 slips completely, the target gauge pressure should be reduced by one twelfth while the tendon is stressed to the required original elongation.

For example, if there are 12 strands and the target elongation is 152mm (6in) and slip of 50mm (2 in) occurs on one strand and 75mm (3 in) on another, the target gauge pressure should be reduced by (2+3) / (6*12). (If this example actually occurred on site, then operations and equipment should be examined carefully and appropriate action taken to rectify the problem.)

In order to attain the required final force in a tendon with slipped strands, the slipped strands may be stressed individually to their final elongation and force level using a single (mono) strand jack after stressing the remainder. However, care should be taken because the slipped strands may be trapped and, although they probably can be stressed to the required strand force, it is unlikely that the elongation will be attained. The Engineer should be present when work on a tendon with slipped strands is in progress.

If slip occurs upon release of the jack after otherwise stressing the tendon to full load and elongation without mishap, then it can be corrected by stressing the individual slipped strand(s) back to the original elongation using a single (mono) strand jack. Again the Engineer should be present.

The stressing of individual strands needs to be done immediately and should not be postponed. There is always the risk that a zealous worker will cut off strand tails before it is carried out. If and when this happens, the whole tendon needs to be removed and replaced.

3.10.2 Wire Breaks

Sometimes a wire will break in a tendon. If only one or two wires break, it may be a situation that of relatively little concern. For instance, when one wire breaks only 1/7 ^th of a strand's capacity has been lost. On a multi-strand tendon this will be much smaller proportion. A wire break is normally easily recognized by a sharp popping noise. Very often wire breaks will be within the anchor flare cone, possibly at the back of the wedge plate. It may be possible to see these using a borescope or similar visual probe. Most specifications allow up to 2% of the wires to be broken. However, persistent wire breakage should be investigated and action taken to change procedures or equipment to avoid or significantly lessen the problem.

When breakage becomes excessive, it reaches a point where the required force in the tendon is out of tolerance. In such cases, individual strands or whole tendons need to be replaced.

The cause of wire breakage should always be determined. Some possible causes are: overstressing, poor strand, bad wedges, or high friction points in the duct. Overstressing and high friction points show up when the stressing records are carefully examined. Sometimes strands and wedges may simply be at opposite ends of their respective allowable size tolerance ranges and the problem can be easily fixed by using different pieces.

3.10.3 Elongation Problems

Not reaching the required elongation can have several causes. One of the main reasons is a less than perfect tendon alignment. Sudden kinks in the alignment will increase friction loss considerably and consequently reduce elongation.

3.10.3.1 Too small elongation at jacking end under full load

Too small elongation may occur due to a kink close to the stressing anchor; the jack may reach full load, but the elongation will be very small. When this happens, the required elongation may possibly be achieved by stressing the tendon from the other end. However, this will not be feasible if low elongation is due to duct misalignment over the whole length of the tendon.

3.10.3.2 Low elongation for whole tendon

When low elongation is due to duct misalignments occur over the whole length of the tendon, stressing from the other end may not be enough to attain elongation. Consideration may be given to lubricating the tendon with water soluble oil or with graphite powder. This can reduce friction and result in better elongations. After a tendon has been successfully stressed, water soluble oil should be thoroughly removed by flushing. Flushing water should be thoroughly drained and blown from the ducts. Graphite powder may remain in the duct and is, therefore, generally preferred by many Contractors.

3.10.3.3 Elongation greater than tolerance

An elongation can be more than expected. This may be because of less friction than anticipated or because of slip of strands and wedges that went unnoticed. The wedges should be examined at both ends. It is for this reason that marks should always be made on strand tails at both ends the tendon. If there is no wedge slip and tendons persistently give an elongation greater than expected, the stressing calculations should be examined and appropriate adjustments made.

3.10.3.4 Low stressing force

It would be very unusual to not to be able to stress a tendon to a required jacking force; more often a problem is revealed by lack of elongation, not force. If force cannot be attained, the system should be checked. The possibility of increasing the jacking force may be considered. However, it should be checked by calculations using a higher wobble and friction coefficient to make sure that the stress in the tendon after anchor set does not exceed allowable stresses.

3.10.3.5 Overall Tolerance on a Group of Tendons

If none of the above lead to a satisfactory solution, it is possible to consider a problematic tendon as part of a whole tendon group - for example, one tendon out of perhaps sixteen to twenty in a cantilever, or similar. A tolerance for the whole group should be given in specifications or project special provisions. If all other tendons have a good stressing record, one poorly stressed tendon ought not to influence the group tolerance too adversely.

To make up for a loss of force in one tendon a compensating increase in force in other tendons may be considered, if there is sufficient reserve holes in the wedge plates to accommodate additional strands. Alternatively, if the shortfall is significant, it may be necessary to introduce or install additional tendons through provisions made on the plans or shop drawings.

3.10.4 Breaking Wedges

Sometimes wedges break. This causes the loss of the whole strand. It falls under the category of slipped strands and should be treated as such. When a few wedges break on the same tendon, all wedges should be considered potentially defective. The whole batch of wedges should be examined and, if necessary, replaced.

Very often wedges show radical cracks in their visible ends after seating. Experience shows that this is usually a localized cracking of the annular lip containing the retainer ring. Providing the strand has not slipped and providing this type of crack does not extend into the barrel of the wedge, then it is not of any major concern.

Repeated slippage problems and large cracks in the gripping nose of wedges are cause for concern and should be remedied.

Table 3.1(a) Example 1: Elongation of Profiled Tendon in Four-Span Girder (Fig. 3.2)

Table 3.1(b) Example 1 continued: Elongation of Profiled Tendon in Four-Span Girder (Fig. 3.3)

Table 3.2 Example 2: Elongation of External Deviated Tendon in End-Span (Fig. 3.4)

Table 3.3(a) Stressing Report - Example 1: Profiled Tendon in Four-Span Girder (Fig. 3.2 and 3.3)

Table 3.3(b) Stressing Report - Example 1 continued: Profiled Tendon in Four-Span Girder (Figs 3.2 and 3.3)

United States Department of Transportation

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Kemko Injection

Find an Applicator Kemko Bonders > Kemko Injection Kemko Grouts Kemko Coatings Kemko Binders ASTM C 881 Chart Product Spec Template Product Data/MSDS Projects Tech Links - FAQ's - Structural Concrete Repair - Crack Injection Specification - Surface Preparation - Bonding Old-to-New Concrete - Intro to Construction Polymers - Plate Bonding - Coating Guide Kemko Product Equivalents

The Kemko Injection Process (KIP) method of injecting cracks down to 0.002 inches wide for their full depth generally uses a Kemko epoxy adhesive without the additional labor time and costs of installing plastic ports. When the injected adhesive cures, it seals the crack entirely and also restores the concrete to its original monolithic integrity. Kemko's epoxy crack injection specification provides a set of guidelines for this process. Injecting repairable cracks will: Restore structural and/or design strength to the cracked concrete structure, > Eliminate concrete spalling initiated by cracking and aggravated by freeze thaw cycling, > Prevent corrosion of reinforcing steel and pre-stress tendons by encapsulating them against moisture, > Stop the leakage of water and fluids through concrete structures, > Repair concrete without the unsightly surface marks often caused by standard surface crack repairs. Kemko epoxy crack injection products are specifically designed for machine application using our specially engineered Model B injection pump. All resins are 2:1 ratios, 100% solids and contain no solvents or fillers. We make the industry's widest selection with specialized materials for architectural precast panels, underwater, low and high application temperatures, high structure temperatures, chemical and radiation resistance, large voids, narrow cracks, plate bonding, wooden beams, and structures subject to vibration during cure. For cracks where the backside cannot be sealed, we offer a special slump pumping (very fast-set) resin or alternative non-slumping structural paste adhesive. All Kemko structural injection adhesives exceed ASTM C 881, Type IV specifications for load bearing applications. Applications > Beams, Columns and Precast Panels > Buildings, Floors, Walls and Parking Decks > Bridges, Dams, Piers, and Pilings > Water Treatment Plants, Tunnels and Pipes > Tank Bottom Grouting > Highways and Airport Pavements > Elevated Slabs and Platforms Kemko injection seal paste adhesives are used in tandem with the epoxy injection resins. The substrate, surface profile and appearance, application conditions, and project size and complexities are factors to consider when selecting from our wide variety of viscosities, gel times, temperature ranges, and other handling properties. Other Kemko product categories containing possible surface seal products are the Kemko Bonders. For large lineal footage applications, we make several seals in a 1:1 ratio available in 5-gallon pails for automatic metering pumps. StripSEAL is a rapid-setting peelable seal and is the best choice for architecturally sensitive applications to maintain an unblemished appearance (see description below).

Kemko Injection Product Primary Uses Features 038 Regular IR Workhorse injection resin for the repair of structural cracks and delaminations in concrete. Steel plate bonding. Bolt grouting. ASTM C 881, Type IV, Fast strength, cures under vibration, Used in hot climates 030 HiAmb IR When ambient temperatures exceed 90 F. Relatively long potlife. Structural concrete repair. Steel plate bonding. Bolt grouting. ASTM C 881, Type IV, Fast strength, cures under vibration 068 LoVis IR Injection resin for the repair of cracks and delaminations in concrete. Low viscosity for use with fine cracks down to 5 mils and at low application temperatures. ASTM C 881, Type IV, Fast strength, cures under vibration, Cold weather suitable 050 Slump IR Repair of slabs and walls where opposite side cannot be sealed. Short potlife, extremely fast cure. Extremely fast set, Low cost 165 HiTemp IR Injection resin for structural concrete repair and steel plate bonding at high structure temperatures. ASTM C 881, Type IV, Industry highest HDT for hot environments 077 Large Void IR Long potlife, low exotherm on cure for repair of honeycombed concrete, large voids and delaminations. Excellent for many void-grouting applications under tanks and equipment. Minimal heat generation, Long mixed useful life, Long travel applications, High chemical and radiation resistance 026 UW IR Underwater repair of concrete structures in fresh or saltwater. Pier and piling repair using steel or fiberglass jackets. ASTM C 881, Type IV, Best underwater product 046 QuikSEAL Fast set crack seal, excellent grindability, low odor. Sets up in about an hour for crack injection. Easy mix 1:1 ratio. For overnight set, use Bonder Paste, Long Work Life. Workhorse rigid injection seal 136 StripSEAL™ Fast setting, strippable seal for injection repair in 30-40 minutes. No grinding required. No odor. Flexible for use on moving cracks. Peels off like a tape. Often used on architectural precast surfaces. Easy cleanup saves labor costs. Sets at 20°F, Won't crack. 022 SuperSEAL Very fast setting seal, sets below 30°F, can inject in 45 minutes, deodorized mercaptan cure. Fastest cold weather rigid seal in dry conditions 019 LoTempSEAL Same day cure, use at low temperature. Very high bond strength and best damp/wet bond of our pastes. Best cold weather seal under damp conditions 104 Underwater Putty Hand mixable putty for injection seals and underwater spall repair Can be mixed underwater KEMKO Product Designation 038 Regular IR 030 HiAmb IR 068 LoVis IR 050 Slump IR 077 Large Void IR 051 LoMod IR 026 UW IR 165 HiTemp IR Features Workhorse Resin for Structural Repair Structural Repair at High Ambient Temperature Low Viscosity for Tight Cracks and Low Application Temperature Fast Initial Set for Slump Pumping and Crack Repair without Back Seal Filling Large Voids, Grouting Low Exotherm High Rad. Resist. Flexible Resin, Low Modulus to Allow for Movement Excellent Bonding in Underwater Use. Cures below 40° F High HDT for High Service Temperature Application Temp. Range, Degree F 40-95 85-125 <40-95 60-90 50-120 50-95 <40-90 60-100 Viscosity, cP, Mixed 350 350 200 500 250 275 250 500 Gel Time, minutes 14 25 21 7 >210 25 16 16 Tensile Strength, psi 9,000 9,300 9,000 6,000 6,500 2,200 8,000 8,000 Elongation at Break, % 2 2.5 2 2.5 70 2 1.5 Compressive Yield Strength, psi 16,000 15,600 16,000 16,000 11,000 15,000 16,500 Modulus, psi 400,000 405,000 410,000 500,000 310,000 320,000 340,000 Flexural Strength, psi 12,000 10,600 12,000 11,000 8,500 9,500 11,600 Modulus, psi 550,000 320,000 490,000 450,000 250,000 300,000 550,000 Heat Deflection Temp, Degree F 140 140 140 110 108 135 165 Wet Slant Shear Strength, psi >4,500 >4,500 >4,500 >4,500 >4,500 >400 >4,500 >4,500 Top of page

Emecole, Inc.
P.O. Box 7486
Romeoville, Illinois 60446
800-844-2713
email: lcole@emecole.com

Cracks should be routed to ½"1/2" minimum. Clean all foreign matter that might interfere with adhesion. Install Ethyl-Foam or sand to prevent Epo-Toxy from running into sub-base. Moisten a rag with Xylene or any aromatic solvent and wipe clean to remove dust and ensure adhesion.

Stir Epo-Toxy™ throughly. Resin and Hardener are manufactured with multiple viscosity products. It is important to stir or roll containers prior to mixing.

Mix measured one (1) part Hardener "B" and one (1) part Base "A". Proper measurement by volume must be adhered to completely.

Mix with slow speed drill and mixer. (Use a 5 gallon plastic pail for a mixing container.) Add pigment while mixing if desired.

Pour mixed compound into a plastic garden type watering bucket for distributing to cracks. Compound is self leveling.

Broadcast sand blasting sand over entire crack joint o prevent tracking while curing and to blend color to existing surface.

Note: Lay strips of masonite or similar material over cracks if necessary to open to traffic quicker, this will allow time for compound to cure.

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