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Direct Stress, Deformation, and Design
Published in Robert L. Mott, Joseph A. Untener, Applied Strength of Materials, Sixth Edition SI Units Version, 2017
Robert L. Mott, Joseph A. Untener
Bearing stress is computed in a manner similar to direct normal stresses:For flat surfaces in contact, the bearing area is simply the area over which the load is transferred from one member to the other. If the two parts have different areas, the smaller area is used. Another requirement is that the materials transmitting the loads must remain nearly rigid and flat in order to maintain their ability to carry the loads. Excessive deflection will reduce the effective bearing area.
Bearing fatigue behavior of heat-resistant polymer composites
Published in Yasushi Miyano, Albert H. Cardon, Ken L. Reifsnider, Hiroshi Fukuda, Shinji Ogihara, Durability Analysis of Composite Systems 2001, 2020
T. Hamada, K. Ohiwa, H. Fukuda, H. Tsuda, K. Kemmochi
Bearing strength decreased with increasing test temperature. The drop in bearing strength at high temperature was 7% at lower clamping pressure, while that was 22% at higher clamping pressure. At strong lateral constraint, the bearing strength dropped considerably at high temperature. Regardless of clamping pressure, the maximum bearing stress at high temperature reduced by about 20%.
Experimental and numerical study on the structural performance of the stainless steel ring strengthened removable dowel bar connection system
Published in International Journal of Pavement Engineering, 2022
According to American Concrete Institute (ACI) subcommittee 325 (1956), the allowable bearing stress in concrete is determined according to Equation (16). Where fb is the allowable bearing stress and d is the dowel bar diameter. Considering the dowel bar of 32 mm diameter, the allowable bearing stress is 29.15 MPa with a concrete compressive strength of 31.92 MPa. However, this allowable bearing stress is independent of the number of loading cycles and the concrete age. Therefore, the reliability of this allowable stress should be further assessed. Equations (17) and (18) proposed in CEB-FIP Model Code 2010 were adopted to calculate the fatigue compressive strength considering the concrete age (CEB-FIP 2010), where, βcc(t)fck is the concrete compressive strength at various ages; s = 0.2 when CEN 52.5 N cement is used; βc,sus(t, t0) is taken as 0.85 for the fatigue loading. As a result, the fatigue compressive strength after 40 years calculated by Equations (17) and (18) was 30.30 MPa. Then the typical S-N relationship proposed in the CEB-FIP Model Code 2010 was used to calculate the allowable bearing stress under different loading cycles, as expressed in Equations (19)–(23), where, N is the total number of loading cycles; Sc,max and Sc,min are the maximum and minimum compressive stress ratios under cyclic loads calculated by Equations (22) and (23), respectively. This relationship was plotted as the typical S-N curves, as shown in Figure 33. When Sc,min is equal to zero, the maximum allowable bearing stress determined by Equation (19) was from 13.64 MPa to 17.80 MPa with loading cycles from 106 to 108. The normal contact stress at the joint surface was then compared with the allowable bearing stress. According to ACI Subcommittee 325, apart from specimens 32D and 32D4T, other specimens could meet the bearing stress requirement under 20 kN service load. However, after considering the number of loading cycles and the concrete age by Equations (17)–(23), employing the stainless steel ring with at least 15 mm thickness could meet the fatigue requirement under cyclic loads.