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Lining contact pressure and ground deformation of Raghadan transportation tunnel (Amman, Jordan) were investigated. The tunnel is 1.1 km in length and 13.5 m in diameter. This study was intended to integrate useful relations among the widely used rock classification system (RMR: rock mass rating), Hoek-Brown classification, and liningground interaction. The materials encountered along the tunnel alignment were limestone, dolomatic limestone, marly limestone, dolomite, and sillicified limestone. The ground conditions along the tunnel alignment including bedding planes, joint sets and joint conditions, rock quality, water flow, and rock strength were evaluated based on the drilled boreholes and rock exposures. Elasto-plastic finite element analyses were conducted to study the effect of rock mass conditions and tunnel face advance on the behavior of lining-ground interaction. The results of the analyses showed that lining contact pressure decreases linearly with the increase in RMR value. Also the results showed that tunnel lining contact pressure and crown inward displacement decreases with the increase in the unsupported distance (distance between tunnel face and the end of the erected lining). Ground displacement above the tunnel crown was found to be increases in an increasing rate with the decrease in the depth above the crown. This displacement was also found to be affected by the RMR value and the unsupported distance.

Advancement in bridge design/construction technologies altered typical bridge parameters utilized in the development of AASHTO LRFD live-load distribution factors developed more than two decades ago. A girder bridge constructed using high-performance, high-strength concrete has been instrumented and tested under controlled-load condition. AASHTO LRFD distribution factors were compared to the factors computed from girders measured strains. AASHTO LRFD distribution factors were on average 21% higher than computed factors. A detailed finite element model (FEM) was developed and calibrated to match the controlled load test results. Several variations of the FEM were created to account for the presence of end & intermediate diaphragms, girders continuity, and bridge skewness. The addition of end diaphragms decreases distribution factors on average by 6% while addition of intermediate diaphragms redistributes the moments between interior and exterior girders. Effect of diaphragms was more evident for bridge with large skew angles and less significant for skew angles less than 20 • . Bridges with skewness have decreased distribution factors which was evident for skew angle in excess of 20 • ; AASHTO LRFD has good estimates of skewness effect on distribution factors. Considering the continuity effect in the calibrated FEM revealed that AASHTO LRFD distribution factors are overestimated on average by 17%.

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