Angled Coring – Detailed Overview

What Is Angled Coring?

Angled coring (also called inclined coring) is a method of core drilling holes at a specific angle rather than the standard vertical or horizontal direction. This technique is performed using core drills mounted at calculated angles, allowing contractors to access or bypass structural features while maintaining drilling precision.

Primary Uses of Angled Coring

1. Obstruction Avoidance

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  Drilling at an angle is ideal when rebar, post-tension cables, or embedded utilities are in the path of a standard core.

  
  


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  Enables safe routing around existing obstacles in floors, walls, or ceilings.

  
  

2. Duct, Conduit, and Pipe Routing

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  Commonly used in mechanical, electrical, and plumbing (MEP) systems where angled entry points are required.

  
  


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  Useful in tight spaces where straight-line drilling is not possible.

  
  

3. Structural Retrofit and Anchoring

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  Creates angled holes for dowels, anchors, or reinforcement bars that need to be embedded diagonally for added pullout strength or load direction.

  
  


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  Used in seismic retrofitting to add shear resistance or tension capacity to structural elements.

  
  

4. Drainage and Ventilation Installations

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  Facilitates installation of sloped drains or ventilation outlets for gravity-based flow, especially in parking decks, basements, or tunnel walls.

  
  

5. Testing and Core Sampling

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  Enables engineers to obtain core samples from difficult-to-access locations or to reach a specific target area within the concrete without damaging overlying finishes.

  
  

6. Post-Tension Cable Routing (Careful Application)

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  In select situations, angled holes are used to reroute or supplement post-tension systems, though this requires extreme precision and structural analysis.

  
  

Angled Coring Process Overview

Equipment:

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  Diamond-tipped core drill

  
  


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  Adjustable-angle rig or mount

  
  


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  Cooling water supply

  
  


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  Core barrels of appropriate diameter

  
  

Steps:

1. 
   

   Survey & Scan the Area

   
   
   
   
   
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     Use GPR (Ground Penetrating Radar) or X-ray to detect embedded elements.

     
     
   
   
   
   


2. 
   

   Set the Angle

   
   
   
   
   
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     Mount the drill on an adjustable rig and align it to the desired inclination (often between 15°–75°).

     
     
   
   
   
   


3. 
   

   Anchor the Rig

   
   
   
   
   
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     Drill must be securely fixed to prevent slippage during angled operation.

     
     
   
   
   
   


4. 
   

   Drill Slowly with Cooling

   
   
   
   
   
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     Use water to cool the bit and suppress dust.

     
     
   
   
   
   


5. 
   

   Extract Core or Complete Hole

   
   
   
   
   
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     If coring for testing, remove the cylindrical core; if for utility routing, clean and prep the hole.