A complete study of bearing stress in single bolt connections

Self Cite

The paper deals with bolted connections of angles connected by one leg subjected to tension force. These connections are characterized by the eccentricity of the tension force and are dealt with in the EN 1993-1-8 standard that provides the design resistance for block tearing, for bolt bearing and for reduced effective net cross-section that is based on β factors. A closer look on the design resistance of the reduced effective net cross-section shows that the calculation of β may lead to inconsistencies. An addition of a bolt may lead to decrease of the net cross-section resistance. Moreover, the formulas for the calculation of the reduced net cross-section resistances are only a different presentation of the formulas for the block tearing resistance. Analysis of 631 test results from literature shows that the calculation of the block tearing resistance is sufficient and that equations 3.12 and 3.13 of EN 1993-1-8 are redundant. The study will also show that a constant distribution of stress on the tension face may be assumed in the formula for the block tearing resistance of the angles connected by one leg in tension (eq. 3.9, EN 1993-1-8), similarly to the provisions in American standard AISC 360-05. A modified bolt bearing strength function is also presented and statistically analysed on 631 test results. It is simpler and less conservative than the one in EN 1993-1-8.

Section: Analysis Of the Design Resistances Given In En 1993-1-8mentioning

confidence: 99%

Section: Analysis Of the Design Resistances Given In En 1993-1-8mentioning

confidence: 99%

13.10: Angles connected by one leg in tension

Može

2017

Self Cite

“…To find a more accurate expression to describe the relationship between bearing resistance and end distance, experimental results from different researchers [11][12][13] and the background document of Eurocode 3 [14][15][16] were summarized in addition to the test results presented in this paper. Test results of net cross-section failure were not included since they were controlled by net cross-section check.…”

Section: Comparison With Design Codesmentioning

confidence: 99%

01.08: Bolted bearing connection with high strength steel and grade 12.9 bolt

Wang

Lyu

2017

This paper presents an experimental program investigating the behavior of high strength steel connections consisting of one bolt in double shear. A total of 15 bolted connections fabricated from three grades of high strength steel with the nominal yield strengths of 550 MPa, 690 MPa and 890 MPa were tested. The effects of end distance and steel grade on the bolt bearing behavior were evaluated. The bearing resistances of the bolt on various high strength plates were determined and compared with respect to the tensile strength of the plates. The bolt hole elongation due to bolt bearing on high strength steel plate was measured and its implication on the plate bearing resistance was discussed. The test results were compared with Eurocode 3 and AISC 360-10 predictions and it was found that Eurocode 3 could be used conservatively to predict the bolt bearing resistance on high strength steel with nominal yield strength up to 890 MPa whereas AISC 360-10 method tends to overestimate the bearing resistance of the bolted connection. A regression analysis was performed based on the test data and those from the literature so that a more general method was proposed to predict the bolt bearing resistance on normal strength and high strength steel plate.

“…Hard contact in normal direction and friction contact in tangential direction were assigned to the contact pairs, with friction coefficient ranging from 0.05 to 0.25 between plates and between bolt shank and plates, respectively. The numerical model was in general adopted from [5].…”

Section: General (Lagrange Models)mentioning

confidence: 99%

01.10: Different approaches towards numerical modelling of bolt bearing

Jakše

Može

2017

Self Cite

Bolt bearing is characterized by large plastic deformations that occur mainly near the contact between bolts and plates and may possibly lead to fracture. Numerical modelling of such behaviour is not trivial. The paper focuses on the procedures for numerical analysis that allow numerical modelling of bolt bearing up to fracture. The commercially available software Abaqus software was used for this purpose, taking the advantages of built-in material models and numerical procedures without introducing the user subroutines. The problem of bolt bearing is assessed using static stress analysis, explicit analysis and coupled Eulerian-Lagrange analysis. The fracture model considered is based on stress modified fracture model and relies on the accumulating damage and on the reducing stiffness of finite elements to the point, where they offer no resistance and can be either removed from the model or are left with negligible stiffness. The required parameters (stress triaxiality, equivalent plastic strain to failure and displacement to failure) were determined from the experimental data. A few different bolted connections with different types of failure are analysed with full failure model and the results are compared with experiments. The advantage of Eulerian meshing is considered, where excessive plastic deformations lead to contact problems. Coupled Eulerian-Lagrange analysis with model parts expected to have large deformations were modelled with Eulerian approach and the rest with more conventional Lagrange approach. Diverse material models, element options, time step and their impact on numerical simulation were compared and optimized for speed and accuracy.