Epoxy Injection of Structures Part 3

February 24, 2017

This is the third in a series on Infrastructure Repairs Using Epoxy. Part One is  Introduction to Epoxy Injection.  Part 2 is Crack Analysis Before Epoxy Injection

If your have not read that yet you may want to go back and read it before you proceed with reading this.

Port Setting

It is extremely important that if drilling to use the right tool. to set drill type ports use a vacuum swivel drill. That is a drill with vacuum attached swivel drill chuck and hollow a drill bit.

Concrete dust can be detrimental to the injection processes in several ways. Any dust remaining in the drill hole near a crack can combine with the very low viscosity injection resin. This thickens your resin turning it into a weak paste. This paste can slow or even block the resin flow. Drilling very tight crack with a solid drill forces dust into the crack. This seals the crack from resin flow. Do not allow shortcuts in the drilling procedures!  However, for most applications the surface port is the easiest and most effective method.Epoxy Injection Surface Port

Port Spacing

Determining the spacing of ports is done by a highly experience applicator. This spacing is a factor of the tightness of the crack and the depth of the concrete substrate. Spacing is normally between four (4) and eight (8) inches.

Port Setting and Sealing

Align ports directly over cracks. That allows injection resin to flow into the crack. Seal surface cracks. Sealing the exterior of cracks is done with Epoxy Gel type Bonder.

Testing The System

Test cracks that are ill defined, or if dust or debris is in the crack. This testing may be done by injecting water into the crack area.

Water left in the cracks will not effect the injection process or the curing of the Epoxy.com Injection Resin. Heavier injection resin forces the water out the cracks. Water injection helps clean the cracked areas. More important, is that it helps avoid the unexpected. This process of flushing the cracks is commonly skipped by more experience contractors, who can tell if there will be a flow of resin, by just looking at them. However, when in doubt water testing is a must.

If the cracks contain algae, chlorinated water containing copper sulfate is injected. After pumping this mixture is left over night. The next morning the crack is flushed by pumping fresh water, into it. This flushes it out before resin injection begins.

Efflorescence builds up on the bottom of a crack in a horizontal slab. Water in the crack extracting soluble calcium hydroxide is the cause. The water evaporates at the surface leaving the lime, which later reacts with the carbon dioxide in the air to form limestone. The inside of the crack, is frequently free of limestone and making it suitable for injection.

Part 4 of this series: Injection Resin Materials Product Selection.

For more information visit our website at http://www.epoxy.com, email us at info@epoxy.com or call our technical service department at +1 (352) 533-2167.

 


Epoxy Injection of Structures

February 10, 2017

Infrastructure Repairs Using Epoxy

Epoxy Concrete Injection Epoxy Wood Injection, epoxy crack repair

Epoxy Structural Concrete and Wood Repair / Waterproofing

The following article is written with enough information about resin injection systems to help protect the Owner from the misuse or improper installation of an injection systems.   For more information contact me: Norm Lambert.

Part 1: Introduction to Epoxy Injection

Epoxy Concrete Injection Epoxy Wood Injection, epoxy crack repair

One of the most versatile, problem solving products available in epoxy systems today is Epoxy Injection Resin. Epoxy.com Epoxy Injection of a bridge abutmentStructural restoration of concrete by epoxy injection is very often the only alternative to complete replacement. It therefore results in large cost savings. Injection protects the rebar and stops water leakage.

Epoxy injection of concrete cracks has been used for decades. When properly installed it is still working as well as it did right after it was installed.

Epoxy Injection Resin is a system for welding cracks back together. This welding restores the original strength and loading originally designed into the concrete. Epoxy injection restores the structural qualities the concrete design intended. In other words under most conditions it makes the concrete as good as new. It creates an impervious seal to air, water, chemicals, debris, and other contamination.

Other waterproofing injection systems like urethane resin will seal the crack from water but will not repair the the member structurally.  That makes the structure member vulnerable to additional structural decay. This structural advantage that an epoxy injection repair gives, makes it the best choice for most situations. Epoxy or Urethane Injection discusses when to use epoxy and when to use urethane.

A crack, obviously, is a sign of failure caused by stresses, inadequate design, improper curing, etc. One of the dangers of a structural crack is the effect that it has on the reinforcing bar. The reinforcing represents one of the main structural values of the concrete.

Cracks left unprepared allow moisture, road salts and other contaminants to penetrate and attack the rebar. The rebar deteriorates, losing the structuEpoxy Injection of concreteral value. Loosing the entire structure is often the result.

Epoxy injection resin has two purposes. First, it effectively seals the crack to prevent the damaging moisture entry. Secondly, it monolithically welds the structure together. Most people assume that this welding of the structure is the most important result of the repair. Actually what is most important is the sealing.

The sealing properties of the injection prevents premature deterioration of the reinforcing. This can be of equal, or in some cases greater importance than the structural welding. It would theoretically always be desirable to get this welding effect.

Next in The Epoxy Injection Series:

Injection Part 2 – Crack Analysis

For more information visit our website at http://www.epoxy.com, email us at info@epoxy.com or call our technical service department at +1 (352) 533-2167.


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