- Open Access
Strength analysis of adhesive joints of riser pipes in deep sea environment loadings
© Zhang et al.; licensee Springer. 2013
- Received: 2 September 2013
- Accepted: 30 October 2013
- Published: 30 December 2013
Nowadays, adhesive joints are widely used in riser pipes, which are subjected to many kinds of loadings in deep sea, such as external pressure, internal pressure, tension, torsion, bending, and also a combination of these loadings. Adhesive joints of riser pipes are the most dangerous parts in term of strength, as singular stress fields exist at the end of the interface between the adhesive and the adherends, so it is very important to evaluate the strength of adhesive bonded joints for riser pipes in deep sea environment loadings. In this research, the strength of adhesive joints of riser pipes is studied under external pressure, internal pressure, tension, torsion, bending loadings, and it is found that singular stress fields exist around the end of the interface. The riser pipe under external pressure, internal pressure and tension loading is more prone to break than under bending and torque loading.
- Adhesive bonded joint
- Singular stress field
- Riser pipe
- Sea environment
Due to low manufacturing costs, low stress concentration and ease of maintenance, adhesive joints are most frequently used in numerous industrial sectors such as automobile, shipbuilding, aeronautical, etc., replacing or supplementing traditional joining technologies, such as welding or riveting. Adhesive bonded joints are also widely used in riser pipes because of their light weight, high strength, and high corrosion resistance. With the wide use of adhesive joints, many research works have been done to evaluate their strength including experimental and analytical methods [2–8].
The mismatch of different materials properties may cause stress singularity at the end of the interface between different materials, which leads to failure of the bonding part in structures, so it is very important to analyze the stress singularity field for evaluating the strength of adhesively bonded joints. Many researchers did some valuable work to analyze the stress singularity field at the end of interface between the adhesive and the adherends, such as Koguchi et al. , Kilic et al. , Van Tooren et al. , and Goglio and Rossetto , Tilscher . Zhang  proposed one easy method to evaluate the effect of adhesive thickness and length on the strength of adhesive joints. Moreover, Zou and Taheri  analyzed stress distributions of adhesive bonded sandwich pipe joints subjected to torsional loadings. Da Silva et al. made a detailed and comprehensive comparion between studies about adhesively bonded joints [16, 17].
Here r, θ are the polar coordinates around the interface edge, a, β are Dunders’ parameters which are expressed by Possion’s ratio v and shear modulus G.
In this paper, the scaling model with the following dimensions was used: adhesive thickness h0 = 6 mm, cover thickness h1 =10 mm, total length 2 L = 200 mm and coupling length 2c = 25 mm. The outer diameter of the adherend was 140 mm and the inner diameter was 110 mm. The adherend steel elastic properties were E = 70,000 MPa, v = 0.33. The adhesive material elastic properties were E = 3500 MPa, v = 0.30, which means that the existence of singular stress fields condition a(a-2β) > 0 is satisfied at the edge of interface between adhesive and adherend.
The commercial software ABAQUS was used to perform the analysis. The finite element method model was constructed using 3-D solid elements (Figure 3). Two mesh densities were used to conduct the analysis. A coarse mesh with the mesh density of 32 rows of elements circumferentially 2 rows (radially) · 30 rows (axially) was used to model the pipe region, while the mesh density was doubled to model the joint region. Moreover, the mesh of the joint region was graded along the axial direction of the pipe, finer toward the free edges of the joint.
External pressure loading case
Internal pressure loading case
Generally, the internal pressure of a riser pipe is higher than the external pressure to prevent buckling of the pipe, and in this research, an internal pressure P ip = 15.0 MPa was chosen. The boundary conditions for this case were: u r = 0, at x = 0; u x = 0, x = 0; and u s = 0, x = 0.
Tension loading case
Bending loading case
Torque loading case
Comparison of stress intensity fields between the cases of external pressure, internal pressure, tension, bending and torque loading
Stress values at the end of the interface are related to the element sizes, and models under different loading cases have the same mesh sizes in this paper. From the comparison, it can be said that different loading cases have different gradients of stress lines. The gradient of stress lines indicates the index of the singular stresses singularity at the end of the interface. If the loading values increase, the stress values at the end of the interface will also increase, without changing the gradient of the stress lines. So the gradients of stress lines are only related to the loading conditions if the mesh sizes do not change.
In this paper, a 3D adhesive joint model was constructed using FEM, and the singular stress field around the end of the interface between the adhesive and the adherend was analyzed for cases of external pressure, internal pressure, tension, bending and torque loadings. Singular stress fields exist for all the loading cases, and the stress singularity is larger for cases of external pressure, internal pressure and tension loading compared to the cases of bending and torque loading, which means that the riser pipe under external pressure, internal pressure and tension loading is more prone to break than under bending and torque loading in deep sea environment.
The authors appreciate the reviewer’s constructive comments and detailed feedback for improving the manuscript. This research was supported by Science Foundation of China University of Petroleum, Beijing (No. 2462013YJRC44), and the National Basic Research Program of China (973 Program) Grant No. 2011CB013702.
- Saad P, Jahnsen O, Salam MM: Application of composites to deepwater Top tensioned riser systems. OMAE 2002–28325:255–261 2002. doi:10.1115/OMAE2002-28325Google Scholar
- Arenas JM, Narbón JJ, Alia C: Optimum adhesive thickness in structural adhesives joints using statistical techniques based on Weibull distribution. Int J Adhes Adhes 2010, 30: 160–165. 10.1016/j.ijadhadh.2009.12.003View ArticleGoogle Scholar
- Afendi M, Teramoto T, Bakri HB: Strength prediction of epoxy adhesively bonded scarf joints of dissimilar adherends. Int J Adhes Adhesives 2011, 31: 402–411. 10.1016/j.ijadhadh.2011.03.001View ArticleGoogle Scholar
- Azari S, Papini M, Spelt JK: Effect of adhesive thickness on fatigue and fracture of toughened epoxy joints – part I: experiments. Eng Fract Mech 2011, 78: 153–162. 10.1016/j.engfracmech.2010.06.025View ArticleGoogle Scholar
- Hunston DL, Miyagi Z, Schultheisz C, Zaghi S: The sandwich bending specimen for characterizing adhesive properties. J Time Dependent Mater 2003, 7: 71–88. 10.1023/A:1024091302445View ArticleGoogle Scholar
- Park JH, Choi JH: Kweon. Evaluating the strengths of thick aluminum-to-aluminum joints with different adhesive lengths and thicknesses. Compos Struct 2010, 92: 2226–2235. 10.1016/j.compstruct.2009.08.037View ArticleGoogle Scholar
- Suzuki Y: Adhesive tensile strength of scarf and butt joints of steel joints (3rd report, relation between adhesive layer thickness and adhesive strength of joints. Trans Japan Soc Mech Eng 1987, 53: 5146–522.Google Scholar
- Neves AA, Coutinho E, Poitevin A, Van der Sloten J, Van Meerbeek B, Oosterwyck V: Influence of joint component mechanical properties and adhesive layer thickness on stress distribution in micro-tensile bond strength specimens. Dent Mater 2009, 25: 4–12. 10.1016/j.dental.2008.04.009View ArticleGoogle Scholar
- Koguchi H, Hoshi K: Evaluation of joining strength of silicon-resin interface at a vertex in a three-dimensional joint structure. 2012.http://mcweb.nagaokaut.ac.jp/~koguchi/papers/2011/201107-IPACK2011-52065-hoshi.pdf. Accessed 27 December 2013Google Scholar
- Kilic B, Madenci E, Ambur DR: Influence of adhesive spew in bonded single-lap joints. Eng Fract Mech 2006, 73: 1472–1490. 10.1016/j.engfracmech.2005.12.015View ArticleGoogle Scholar
- Van Tooren MJL, Gleich DM, Beukers A: Experimental verification of a stress singularity model to predict the effect of bondline thickness on joint strength. J Adhes Sci Technol 2004, 18: 395–412. 10.1163/156856104323016315View ArticleGoogle Scholar
- Goglio L, Rossetto M: Stress intensity factor in bonded joints: influence of the geometry. Int J Adhes Adhes 2010, 30–5: 313–321.View ArticleGoogle Scholar
- Tilscher M, Munz D, Yang YY: The stress intensity factor in bonded quarter planes after change in a temperature. J Adhes 1995, 49: 1–2. 10.1080/00218469508009974View ArticleGoogle Scholar
- Zhang Y, Noda NA, Takaisi K, Lan X: Effect of adhesive thickness on the intensity of singular stress at the adhesive dissimilar joint. J Solid Mech Mater Eng 2010, 4–10: 1467–1479.View ArticleGoogle Scholar
- Zou GP, Taheri F: Stress analysis of adhesively bonded sandwich pipe joints subjected to torsional loading. Int J Solids Struct 2006, 43(5953–5968):2006.Google Scholar
- Lucas FM, Da S, Paulo JC, Das N, Adams RD, Spelt JK: Analytical models of adhesively bonded joints -- Part I: Literature survey. Int J Adhes Adhes 2009, 29: 319–330. 10.1016/j.ijadhadh.2008.06.005View ArticleGoogle Scholar
- Lucas FM, Da S, Paulo JC, Das N, Adams RD, Wang A, Spelt JK: Analytical models of adhesively bonded joints—Part II: Comparative study. Int J Adhes Adhes 2009, 29: 331–341. 10.1016/j.ijadhadh.2008.06.007View ArticleGoogle Scholar
- Xu JQ, Mutoh Y: Singular residual stress field near the interface edge. Japan Soc Mech Eng 1996, A-62(597):1219–1225.View ArticleGoogle Scholar
- Bogy DB: Edge bonded dissimilar orthogonal wedges under normal and shear loading. J Appl Mech 1968, 35: 460–466. 10.1115/1.3601236View ArticleGoogle Scholar
- Bogy DB: Two edge-bonded elastic wedges of different materials and wedge angles under surface tractions. J Appl Mech 1971, 38: 377–386. 10.1115/1.3408786View ArticleGoogle Scholar
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