INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING Volume 1, No 3, 2010
Copyright 2010 All rights reserved Integrated Publishing services
Research article 2.4 Reaction at the bottom of box
Self weight of box = Weight of top slab + Weight of bottom slab
+ Weight of side walls Total reaction at bottom=Self weight of box +Weight of imposed load
+Weight of live load The boundary condition considered is fixed.
3. Analysis of 2D underpass RCC bridge model
A 2D underpass RCC bridge (Figure 1) is modeled considering 1m length for the following details shown below. Box dimensions: 1mx7.5mx4.1m (LxWxH) (Center to center). In addition to the dimensions mentioned in Figure 3, following parameters are considered for the 2D analysis. Keeping all the parameters same, the analysis is carried out using two methods viz. conventional slope deflection method (manual calculations) and other by using SAP2000 (programming software). The manually calculated values for the bending moment at corner A is 205kNm and corner C is 302kNm for dead load case. For the same corners A & C, the SAP results are found to be 203kNm and 298kN m respectively.
Figure 3: (a) Center to center Dimensions of RCC Underpass Bridge (b) Dimensions of RCC Underpass Bridge
Dimensions of underpass RCC bridge
Clear horizontal opening Clear vertical opening Slab thickness Wall thickness
7m 3.5 m 0.6 m 0.5 m
Outer to outer horizontal width Outer to outer vertical height Length underpass RCC bridge Angle of internal friction (ф) Density of soil (γ) Grade of concrete
8m 4.7 m 1m 25o 19 kN/m3 M40