Pump Anchor Bolt

[nabeel3]

Dear All

This is a general detail for a Pump foundation anchor bolt. Is it required to fill concrete between pipe sleeve and anchor bolt in the below detail? This detail is from Hydraulic Institute standard HI-14.4

 

[HTURKAK]

The following figure is excerpt from API RECOMMENDED PRACTICE 686.

The sleeves should be filled with polyurethane foam or other flexible mastic material to prevent the annular space around the bolt from being filled with grout.







Use it up, wear it out;
Make it do, or do without.

NEW ENGLAND MAXIM

 

[swazimatt]

not sure if this is a pump specific requirement to not fill the sleeve with grout, but I have always specified the sleeves on anchors as it allows the installer of the base plate or pump some flexibility for situations where the anchor bolt may have moved during concreting or the steelwork doesn't quite line up, the sleeve allows the bolt to be moved slightly to line up. I have always grouted it up afterwards, i do not see the benefit of filling it with foam or similar then grouting over the top

 

[nabeel3]

Dear HTURKAK

if there is no grout ,how the anchor bolt will stay fixed.

 

[dik]

Can you use a PVC sleeve the diameter of the anchor bolt? The sleeve doesn't need to be filled. The anchorage is by the metal plate at the bottom. The free shaft allows the bolt to stretch to develop tension.

I'm not sure what the advantage of roughening the surface is, other than just not providing a trowelled finish.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[HTURKAK]

- The bottom portion of the anchor rod fixed in the concrete . Pls look fully engaged nut embedded in the conrete.

- The anchor rod shall be freely stretched along the sleeve to provide preloading will be effective.

- My past experience is , filling the space with polyurethane foam is the best option to avoid condensation built up and corrosion of the anchor rod.





Use it up, wear it out;
Make it do, or do without.

NEW ENGLAND MAXIM

 

[swazimatt]

won't the portion of bolt between top of grout and top of base plate be sufficient to develop tension, just like when steel members are joined to a plate. just about every structural code for design of hold-down bolts in stub columns do not have the void/sleeve, they just show the threaded bar sticking out the top of the column. In my experience the box-out/void/sleeve has always been a construction detail to assist with fabrication issues and anchorage length is calculated from the bottom of the box-out

 

[SwinnyGG]

won't the portion of bolt between top of grout and top of base plate be sufficient to develop tension

A pump is a lot different than a column base. The potential exists for very high vibration loading; the much larger grip length provided by the sleeve around the anchor mitigates vibration loosening of the anchors. It helps with installation too as mentioned by you and others, but the primary function of that long grip length is protection from vibration.

 

[Ingenuity]

Harrison (in his book: The Grouting Handbook - A Step-by-Step Guide for Foundation Design and Machinery Installation Second Edition) recommends 12 times the bolt diamter for the bolt free length.

Also the magnitude of the bolt preload is important to ensure that vibration does not cause bolt loosening, and fraturing.

We had a crusher where the original installation had no bolt free-length, and after a short working life the rods fractured due to vibration/fatigue, and were replaced with high strength anchor rods with long grip lengths and hydraulically stressed to achieve preloading.

 

[dik]

I've generally used 12x min, but was unaware of a source... just something I've picked up...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[nabeel3]

Dear

Our Pump Vendor provided this drawing and we proceeded with this.

.
Anchor Bolts and Levelling screw.

Is this okay .

 

[dik]

These types of anchorage are generally used to allow for 'exact' placement of anchor rods. If a preload is essential, I like to sleeve the anchor rod with PVC piping to reduce the bonding.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[desertfox]

Hi nabeel3

The sleeve around the foundation bolt does not need filling with grout.

“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein

 

[dik]

They often use a large corrugated sleeve to allow anchor rods to be placed in future, for more precise alignment or because they might not know the exact dimensions. Even in these circumstances, the anchor rod can be sleeved with PVC.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik