compare the traffic loads on the culvert with the stresses calculated using the Boussinesq solution.

Traffic loads: Vertical

the Boussinesq equation:

2.2. Traffic loads Culverts shall be designed to resist both vertical and horizontal forces an effect due to the following road traffic loads including W80 wheel and A160 wheel (AS1597.2, 2013) 2.2.1. Vertical loads a. W80 wheel Strength limit state: A=L4L2 = (b + 1.15H)(a + 1.15H) = (0.5 + 1.15 x 1.3)(400 x 10-3 + 1.15 x 1.3) = 3.78m Calculation of dynamic load allowance (DLA), with a fill height above the culvert of 2 metres ore more: DLA 0.4 0.4 -0.1 X 1.3 = 0.205 2 Vertical loads due to road traffic loadings (Wxv): Wv = (1 + DLA)(EP)/A = (1 + 0.205) (80)/3.78 = 25.5 kPa b. A160 wheel Strength limit state: A=L_L2 = (G+b + 1.15H)( + a + 1.15H) = (2+0.5 + 1.15 x 1.3)(0+ 0.4 + 1.15 x 1.3) = 7.57 Calculation of dynamic load allowance (DLA), with a fill height above the culvert of 2 metres ore more: 0.4 0.1 DLA 0.4 X 1.3 = 0.205 2 Vertical loads due to road traffic loading (WLv): Wlv = (1 + DLA)(EP)/A = (1 + 0.205)(160)/7.57 = 25.470 kPa Uniformly loaded rectangular area Consider a uniformly loaded rectangular area as shown in Figure 7.14. For the increase in vertical stress under any corner of this area (points A, B, C, or D), one can find the following after using and integrating the Boussinesq solution (7.4) Ao; = Irec (7.21) where q is the intensity of the load and Irec is an influence factor defined as 1 2mn/m2 +n2 +1 m2 + n2 + 2 2mn/m2 +n2 +1 Iree (7.22) 41 m2 + n2 + m2n2 +1 m2 + 12 +1) m2 + n2 - m2n2 + 1 + tan 1) with B m = Z (7.23) n and L (7.24) It should be noted that the tan- term in this equation should always be positive and in radians, so when m2 +m2+1