Problem #$5(45$ points$)$

A simple bridge has a span length of $100ft.$ center$-$to$-$ center bearings, a total width of $46ft.$ and total roadway width of $43ft.$ The bridge superstructure consists of six AASHTO Type IV girders space& $8ft$ center$-$to$-$center, designed to act compositely with an Sin thick cast$-$in$-$place $($CIP$)$ concrete deck. The wearing surface thickness is $3$ in$.$ which includes the thickness of any future wearing surface. HL$-93$ is the design live load. The bridge cross section is shown in the figure.

Tatal Rridea Width

MATERIAL PROPERTIES

Cast$-$in$-$place deck slab:

Thickness, $t_s=8\mathrm{.}0in.$

Concrete strength at $28$ days, $f_c^{\text{'}}=4000$

Thickness of asphalt wearing surface $($including any future wearing surface$),t_w=3$ in$.$ Unit weight of concrete, $w_c=150pcf$

Unit weight of asphalt wearing surface $=140pcf$

Barrier weight $=326pl\frac{f}{s}$ide

Precast girders: AASHTO Type IV

Concrete strength at release, $f_{ci}^{\text{'}}=5500$

Concrete strength at $28$ days, $f_c^{\text{'}}=7000$ psi

Concrete unit weight, $w_c=150pcf$