Civil Engineer Department

Eng. Fadhel Abbas A. ALMohammad

Vertical Vessel LoadingCalculation

Objectives

Objectives: Types of Vessel.

Vertical Vessel Foundation Design Procedure.

Vertical Vessel Foundation Design Calculation.

Conclusion.

Questions.

Types of Vessel …

Depend of the resting of vessel, there are two types of it:

A small vertical vessel resting on legs.A tall tower vessel resting on skirt.

Design Considerations:

I. Wind & Seismic loads shall be in accordance with Saudi Aramco Engineering Standard SAES-A-112.

II. Foundation design shall be based on approved certified vendor drawing.

III. For general foundation requirements and guidelines, refer to Saudi Aramco Best Practice SABP-Q-002.

IV. The anchor bolts design, type and size to ensure compliance with ACI 318-02 Code.

V. The engineer shall determine whether additional loading may be imposed on the foundation during erection.

A. Criteria:

It is a principle or standard by which something may be judged or decided.

B. Steps of Calculation:

I. Sketch of Equipment:

It is show some specific and important information about the vessel and foundation like:

Overall Height of Vessel.

Height of the Support.

Diameter & Number of anchor bolt.

II. Equipment Data:

It is contain many vary information about the vessel and, foundation. And most of this info. came from the vendor.

III. Live Load:

(Ref: SAES-M-001, Cluase_5.3.5, Table-1)

In this step we need to find the total Live load to use it in our design calculation and, anchor bolts check.

IV. Pedestal Data:

[Ref: SABP-Q-003, Clause- 4.5.1.1]

Specify shape of foundation based on ARAMCO criteria (Square or Octagon shape i.e.).

The following criteria shall be used to determine the size and shape for the pedestal.

V. Load Calculation:

a) Gravity Load.

This par of calculation is to find two things:

First, one is the pedestal weight.

Second, is the total foundation weight.

b) Wind Load. (Ref. ASCE 07-05, Section 6)

Refer to the criteria we take the information that we found, then applied to wind load.

The reason to calculate wind load is to find:

“Base Shear @ the top of pedestal ( t ).

“Moment @ the top of Pedestal(t -m).

c) Seismic Load. (Ref. ASCE 07-05, Chapoter-11,12 & 15)

Refer to the criteria we take the information that we found, then applied to seismic load.

The reason to calculate seismic load is to find:

“Base Shear @ the top of pedestal ( t ). “Moment @ the top of Pedestal(t -m).

“Base Shear @ the top of pedestal ( t ). “Moment @ the top of Pedestal(t -m).

Empty Load Condition

Operating Load Condition

VI. Checking:

a) SOIL BEARING CAPACITY CHECK.

In geotechnical engineering, bearing capacity is the capacity of soil to support the loads applied to the ground.

So, here we need to approve that the maxima load came from equipment (Q max), not more than bearing capacity of soil (qG_LT).

Also, here we need to approve that the minimum load came from equipment (Q min), not less than (zero).

Bearing Capacity is assumed and taken from the geotechnical report.

b) Sliding Check.

In this case need to check if the sliding load more or less than, the factor of sliding force.

The factor of sliding force equal (SLFOSallow = 1.5) .

(Ref : SAES-Q-005_Clause 4.2)

c) Overturning Check. (Ref : SAES-Q-005_Clause 4.2)

In this case need to check if the overturning load (Up-lift) more or less than, the factor of overturning force.

The factor of overturning force equal (OTFOSallow = 1.5) .

VII. STRUCTURAL DESIGN OF PEDESTAL

There are three types of bars in the foundation and pedestal, as shown below:

a) Design of Vertical Bars.

b) Design of Horizontal Ties.c) Top Face Bars.

b) Design of Horizontal Ties.

c) Top Face Bars.

a) Design of Vertical Bars.

It is used to resists the tension force, it will cause from the loadings are based on load combination provided in ARAMCO standards.

It is used to resists the shear force, it will cause from the loadings are based on load combination provided in ARAMCO standards. .

It is used to resists the shrinking and cracks , it will cause from the High temperature.

VIII. Calculation of Anchor Force.

Calculate the anchor bolts to see if it resist the shear force.

Most of all time no shear force in anchor bolt, because the load resisted by friction load.

Check of anchor bolts to see if the design strength are higher than the applied load, so if they are, then we will declare that the selected bolt size is safe, or go for next higher size.

Cast-in anchors have many benefits, including the following:

They are capable of supporting very large loads.

Drilling or cutting of reinforcement is not required for installation.

Strength is not sensitive to installation procedures and techniques.

Conclusion

Prepare a presentation was a great opportunity for me to add a lot of my knowledge and skills.

It improved my understanding of the vertical vessel and the calculation procedure, keep in touch with modern information about the civil and thinking logically and creatively to solve problems.

Questions