Design Optimisation of FRP Universal Connectors

Abstract

There has been an increased demand for developing special connecting elements for pultruded fibre reinforced plastics (PFRP) structures. The first prototype of a moulded fibre reinforced plastic (FRP) universal connector (UC) was presented to the industry in previous work. The merit of this connector was proven through a full-scale testing program for PFRP beam-to-column connections. In order to develop a series of FRP connections with high structural performance and the lowest possible associated cost, design optimisation techniques must be utilised. For this reason, a design optimisation study on a FRP universal connector was conducted. In evaluating the structural performance of each UC design, finite element analysis was employed. The main objective of the study is to develop an optimum design for the UC by maximising its load carrying capacity and minimising the stress concentration at the critical locations. In order to minimize the number of design variables required for producing the optimum UC, the Taguchi statistical method for quality control was incorporated in this study. In this method, statistically planned experiments are used to identify the settings of the UC design parameters that reduce performance variation. Among the different parameters selected in the study are the UC geometry, composite lay-up, and thickness of the various elements comprising the connector. The results of the analysis indicated that the UC wall thickness, the addition of diagonal webs, and the orientation of the fibres in the webs improve the stiffness significantly. Other design recommandations and conclusions are also presented.

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References

Mosallam

A.S.

, “Connections and Reinforcements Design Details for PFRP Composite Structures”, Proceedings, the 49th Annual Conference, Composite Institute, The Society of Plastic Industry, Cincinnati, Ohio, (February, 1994).

Extern Design Manual, Morrison Molded Fiber Glass Co., Bristol, VA, USA, (1989).

Creative Pultrusions CP Design Guide, Creative Pultrusions Inc., Alum Bank, Pennsylvania, (1988).

Mosallam

A.S.

, “Stiffness and Strength Characteristics of PFRP UC/Beam-to-Column Connections”, Composite Material Technology, PD, Vol. 53, Proceedings, ASME Energy-Sources Technology Conference and Expo, Texas, (January 31-February 4, 1993), pp. 275–283.

Mosallam

A.S.

, “Short and Long-Term Behaviour of Pultruded Fiber-Reinforced Plastic Frame”, Ph.D. Thesis, The Catholic University of America, Washington, D.C., 20052, USA, (1990).

Bank

L.C.

, Mosallam

A.S.

and McCoy

G.T.

, “Male Connections Part of Pultruded Frame Design”, Modem Plastics Magazine, Ed. Toensmeier

P.A.

, McGraw-Hill, (August 1992), pp. 65–67. Also appeared in Modern Plastic International, (August 1992), pp. 34–36.

Mosallam

A.S.

, “Pultruded Composites. Materials for the 21st Century”, Plastics Composites for 21st Century Contruction. Ed. Chambers

R.E.

, American Society of Civil Engineers, NY, NY, (1993), pp. 23–55.

Love

E.A.

and Bisarnsin

, “Experimental Investigation of Self-Tapping Fasteners for Attachment of Corrugated Cladding Panels to Pultruded Fiber Reinforced Plastics Beam in Industrial Building Construction”, Proceeding, ASCE Material Engineering Congress, Atlanta, Georgia, USA, (August 10–12, 1992), pp. 557–584.

Structural Plastics Design Manual, ASCE Manuals and Reports on Engineering Practice, No. 63, ASCE, New York, NY, (1984).

10.

Matthews

F.L.

, “Bolted Joints”, (Section 18) of Composite Design. Tsai

S.W.

, 4th edition, Think Composites Publishing Co., Dayton, Ohio, (1988), pp. 18–3 to 18–16.

11.

Matthews

F.L.

, Kilty

P.F.

and Godwin

E.W.

, “A Review of the Strength of Joints in Fiber-reinforced Plastics, Part 2. Adhesively Bonded Joints”, Composites, (January 1982), pp. 29–37.

12.

Austin

R.B.

, “Adhesive and Structural Plastics”, Proceedings, ASCE Material Engineering Congress, Atlanta, Georgia, (August 10–12, 1992), pp. 560–571.

13.

Sotiropoulos

S.N.

and Ganga Rao

H.V.S.

, “Review of Connectors for FRP Members”, Research Report CFC-93-152, Constructed Facilities Center, West Virginia University, Morgantoum, (February 1993).

14.

Bank

L.C.

, Mosallam

A.S.

and Gonsior

H.E.

, “Beam-to-Column Connections for Pultruded FRP Structures”, Serviceability and Durability of Construction Materials. Proceedings of the 1st Materials Engineering Congress, ASCE Conference, New York, NY, (1990), pp. 804–813.

15.

Mosallam

A.S.

and Bank

L.C.

, “Performance of Pultruded FRP Beam-to-Column Connections”, Proceedings, The 9th ASCE Structures Congress, Indianapolis, Indiana, (April 29–May 1 1991), pp. 389–392.

16.

Mosallam

A.S.

and Bank

L.C.

, “Short-Term Behaviour of Pultruded Fiber-Reinforced Plastic Frame” Journal of Structural Engmeering, The American Society of Civil Engineers, 118, (7), (July), 1973–1954, (1992).

17.

Mosallam

A.S.

, Abdelhamid

M.K.

and Conway

, “Performance Pultruded PFRP Frame Connections Under Static and Dynamic Loads”, Proceedings, the 48th Annual Confaence, Composite Institute, The Society of Plastic Industry, Cincinnati, Ohio, (February 8–11 1993), Session 13–A.

18.

Zahr

, Hill

and Morgan

, “Semi-Rigid Behaviour of PFRP/UC Beam-To-Column Connections”, Proceedings, The ANTEC Conference, Society of Plastic Engineers, New Orleans, Louisiana, (May 9–13 1993), pp. 1496–1502.

19.

Bedewi

N.E.

, Mosallam

A.S.

and Goldsteing

, “Parametric Design Analysis of a Universal Connector for FRP Frame Structures”, Advanced Materials. Expanding the Horizons, Ed. Trabocco

and Lynch

. Proceedings, The 25th International SAMPE Technical Conference, Philadelphia, Pennsylvania, (October 26–28 1993), 25, 622–629.

20.

Taguchi

, Introduction to Quality Engineering. Asian Productivity Organisation.

21.

Quinlan

, “Design Optimisation. Application of Taguchi Methods to Finite Element Analysis”, ASI Taguchi Methods Symposium, (October 1987).