Comparison Between GTStrudl Integrated and Partial Model Analysis Case study: ATF Power Plant CTG&STG Building foundation A Presentation Submitted to: GT STRUDL Users Group24th Annual Meeting & Training Seminar Year

PGESCo.  PGESCo stands for (Power Generation Engineering Services Company).  Established in 1994  Located in Cairo, Egypt  Focused on EPCM Projects (Engineering, Procurement, Construction and Management)  Produced more than 20,000MW 2 2

Table of contents  Introduction  Purpose  STG & CTG Building Integrated Model  Integrated versus partial model analysis  Pile reactions summary table  Pile caps Bending Moment summary table  Advantages and disadvantages of full modeling method  Conclusion 3 3

Introduction  A comparison will be performed between separate models of the steel frame and the foundation ( Partial Model) and a model that combines the steel structure and the foundation (Integrated Model).  The comparison reflects the redistribution of loads on piles and the measure for that will be the difference in pile reactions in both cases. 4 4

Purpose  The purpose of this study is to investigate whether using the integrated model will yield any savings in the number of piles & foundations sizes compared to the conventional approach of partial models. 5 5

Steam Turbine Generator & Combustion Turbine Generator Building Integrated Model 6 6

Pile Caps, piers & Grade Beam Layout 7 7

Pile Springs Layout 8 8

Integrated versus Partial Model Results  The Next Slides will show 3 types of foundation and compare the results between the integrated versus the partial model.  4 Piles foundation.  6 piles foundation.  15 piles foundation. 9 9

4 Piles Foundation Layout 10

Integrated versus Partial Model Results Lateral Dir : ( X – Dir ) 11

Lateral Dir : ( Z – Dir )  Results Summary ( 4 piles found. Lateral Dir)  The Reactions in piles decreases by 55 %.  The maximum pile Reaction decreases by 55 %. 12

Vertical Dir : ( Y – Dir )  Results Summary ( 4 piles found. Vertical Dir)  The Reactions in pile No.1 and No.4 increases by 20 to 25%.  The Reactions in piles No.2 and No. 3 decreases by 18 to 22%.  The maximum pile Reaction decreases by 18%. 13

6 Piles Foundation Layout 14

Integrated versus Partial Model Results Lateral Dir : ( X – Dir ) 15

Lateral Dir : ( Z – Dir )  Results Summary ( 6 piles found. Lateral Dir)  The Reactions in piles decreases by 15 %.  The maximum pile Reaction decreases by 15 %. 16

Vertical Dir : ( Y – Dir )  Results Summary ( 6 piles found. Vertical Dir)  The Reactions in pile No.1 and No.6 increases by 2.6 %.  The Reactions in piles No.4 and No. 5 decreases by 2.7 %.  The maximum pile Reaction decreases by 2.7 %. 17

15 Piles Foundation Layout 18

Lateral Dir : ( X – Dir ) Integrated versus Partial Model Results 19

Lateral Dir : ( Z – Dir ) 20

 Results Summary ( 15 piles found. Lateral Dir)  The Reactions in Some piles increases by 2.4 to 79 %.  The Reactions in some piles decreases by 19 to 28 %.  The maximum pile Reaction decreases by 19 %. 21

Vertical Dir : ( Y – Dir ) 22

 Results Summary ( 6 piles found. Vertical Dir)  The Reactions in Some piles increases by 5.2 %.  The Reactions in Some piles decreases by 6.0 %.  The maximum pile Reaction decreases by 6.0 %. 23

Piles Reactions Summary in Metric Tones Footing types Max single pile reaction M-Tons Total piles reaction M-Tons Partial Model Integrate d Model Diff. % Partial Model Integrate d Model Diff. % 5 Piles footing % % 6 Piles footing % % 8 Piles footing % % 9 Piles footing % % 15 Piles footing % % 24

 Conclusion  The changes in lateral force on piles in both directions X & Z is significant.  It shows that all piles act together to carry the lateral forces so it decreases the maximum pile reaction in the lateral direction.  This will save piles in case the govern design force is due to seismic or wind.  For the Vertical Forces in piles there are changes in the values decreases the maximum pile reaction. And this could save piles 25

Section cut for 9 Piles Integrated Model Section cut for 9 Piles Partial Model Section cut in Pile caps for bending moment results 26

Pile caps Bending Moment summary table in Metric Tones Footing types Bending Moment in short direction in M-tons Bending Moment in long direction in M-tons Partial Model Integrated Model Diff. % Partial Model Integrated Model Diff. % 5 Piles footing % % 6 Piles footing % % 8 Piles footing % % 9 Piles footing % % 15 Piles footing % % A Section was taken at the face of the pier for each pile cap and the results are summarized in the following table: 27

Effects of modeling on the steel structure  Comparison of the bracing and columns forces between the integrated model and the separate steel model. 28

The Steel Building Model 29

The Steel Building with foundation Integrated Model 30

Bracings Results 31

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The Results of Columns 35

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Advantages of full modeling method  Serves to get the optimum number of piles and pile caps size.  Approximate simulation of the exact distribution of the loads. distribution of the loads.  Effect of any modification in structural steel model will be automatically incorporated in the foundation analysis and vice versa. 39

Disadvantages of full modeling method  Regarding The effect on the steel structure, the results shows a great effect on the bracing and column which could help in the reduction of the steel structure weight.  The results of the steel need more time and effort to confirm these reduction. 40

Conclusion  Using the integrated model can reduce the total number of piles for each pile cap. This is achieved specially when the max pile reaction from the partial model analysis exceeds the max allowable pile load by 8%.  Comparing the bending moment resulting from the integrated and partial models proved that The overall change in the values of moments will have no significant effect on the design of pile caps sections.  The Integrated model can reduce the Steel structure weight by using smaller section due to the reduction of forces in the members, we should do more effort to proof this conclusion for the steel. 41