Injection Packer Spacing / Placement
Optimizing Injection Packer Spacing and Placement in Leak-Seal Crack Injection
Injection Packer Spacing
Determining Mechanical Injection Packer Spacing Based on Site Conditions and Product Properties
In the context of leak-seal crack injection, the spacing of mechanical injection packers, also referred to as port spacing, necessitates careful consideration of various site conditions, such as crack width, substrate thickness, water flow, and product properties.
For numerous applications, an initial spacing range of 8 inches (20 cm) to 1 foot (30 cm) on-center is a suitable starting point. However, the presence of hairline cracks calls for tighter spacing, as the limited product dispersion hampers its ability to traverse extensive distances. Consequently, narrower cracks demand closer packer spacing.
Injection Packer Placement
Employing Staggered Injection Packer Placement for Enhanced Crack Intersection and Reduced Concrete Damage
To optimize the efficacy of leak-seal crack injection, contractors should, whenever feasible, employ a staggered injection packer placement strategy.
This entails alternating drill holes to the left and right of the crack and drilling at a 45-degree angle towards the crack, thereby creating a stitch grouting pattern.
Utilizing this technique increases the desired probability of intersecting the crack during drilling and diminishes the likelihood of inducing additional cracking or spalling in the concrete throughout packer installation or the high-pressure injection process.
It is generally advised to initiate the injection process at the lowest point and proceed in an upward direction.