This project had lots of residential, commercial, official buildings, as well as road network. Halcrow acquired the position to investigate the site and design some structures. The chief concern of the client in this project was to produce elegant structures that would be safe and comfortable for road users, easy to construct using local available technologies, and economic to operate/maintain. Additional emphasis was placed on maintaining consistency in the form of structures that would readily blend with the surrounding environment, forming aesthetically acceptable structures that satisfy the requirements of Halcrow Design Criteria. See fig. (32) in the Appendix.
My Role in the Project (in Detail):
1) I chose the most proper structural configurations that involved liaisons and presentations with: the client, architect and Halcrow project director.
2) I undertook the responsibility of leading and coordinating the bridge team to analyze, design as well as produce tender contract documentation. The designs included 3 different underpasses, bridge and retaining walls, see fig (33), and they were:
· The Underpass A (Main Entrance of the Development): our bridge team proposed, compared and presented two alternatives to the client. Fig (34) represents the first alternative which is 2 continuous spans of reinforced concrete voided superstructure. The selected alternative was a portal rigid frame, fig. (35). It had 52 m total length, 24.6 m clear span, with tapered slabs and walls. I assumed the thicknesses for this underpass according to a reference book, then I performed material nonlinear analysis (smeared crack modeling) using ANSYS to optimize the thicknesses according to the stress distribution and failure criteria. After refining the dimensions, I carried out two analytical models to apply the loads and volumetric changes. These two models were: 2D frame model (used in the preliminary stage) has the width as a designed strip (according to AASHTO), and space frame model (used in the detailed design stage), fig. (36), (taking into account the real interaction of the grillage members). The designs for all its sections were controlled with 8 different combinations. Fig. (37) represents detailed reinforcement drawing for slab, wall and foundation of the underpass (A).
· The Underpass B (the Mall Entrance): it was rigid frame. The clear span was 7.9 m with 48 m long, and has one settlement joint located along the upper roadway median. I selected the haunch dimensions to minimize the applied shear, and increase the resultant lever arm against flexural. Fig. (39) represents drawing for the wall of the underpass (A)
· The North-Western Underpass (C): our team proposed two alternatives for this crossing: reinforced concrete box girder curved in plane, fig. (38). Also, reinforced concrete curved box frame which was adopted by the client. I modified the detailed 3D shell element model that was built by the team to account for the effect of curvature on the distribution of the actions.
· The Reinforced Concrete Overpass: This overpass was monolithic frame has provided pleasant aesthetic effects with two 29m clear spans, fig. (41). I designed the cross section as box girder tapered in three different ways: depth of the section (1.2 to 1.6 m), bottom soffit thicknesses, and the thickness of the webs, fig (42). I designed the pier as single tapered polygon column, 14 m height. I used two combined spirals as a solution to protect the concrete core of the section during earthquakes, and to increase the ductility. I calculated the abutments, and it was covered by architectural embankments.
· Retaining Walls: Excel calculation sheets were used, and I checked the designs.
3) Since the underground water table was high on the site, I paid special considerations for waterproofing the underpasses, see fig (40).
4) I built two models for the overpass: The 1st general model consisted of single spine elements (stick model) developed in the initial design stage to get the right general arrangement, and dimensions. The 2nd model utilized 3D shell element and it was used to verify the thicknesses, acquire the detailed forces, such as moment and localized strain intensities in the whole bridge. Also, to determine the optimal reinforcement layouts and cuts related to the contours, fig (43).
5) I carried out 2 seismic analyses for this bridge: Elastic response spectrum using UBC 97, and dynamic analysis using time history loads. Three records were scaled and used: El Centro, Chi Chi, and Kobe. The stiffness for the members was adjusted according to Caltrans SDC. The bridge was designed to be able to deform in a ductile manner beyond its elastic limit.
6) From the beginning of the project, I collaborated with the architect, electrical, and geological engineers, surveyors as well as the water group to achieve detailed drawings and specifications that would meet the requirement of the client. The detailed drawings and specifications for all designs were performed according to Halcrow’s international format, and I used for design: AASHTO LRFD 2007 and Caltrans, figures (45 and 46).
Figure (32) The 8th Gate Development. Sboura, Damascus, Syria. 
Figure (38). The alternative for the crossing B, box girder bridge curved in plane.
Figure (33) The underpasses A) Underpass A, B) Underpass B. C) Underpass C., Syria.
Figure (34) The alternative of the main entrance (A). Voided Continuous slab Bridge.
Figure (36) The Underpass (A). FE model and the related results
Figure (41) The elevation and longitudinal section of the overpass. Tapered Frame Bridge.
Figure (43) represents overpass modeling and results, i.e. shear diagram and stress contours
Figure (44) A) two mode shapes of the bridge
Figure (46) Some of the detailed drawings of the overpass. A) Reinforcement of the box in mid-span. B) Reinforcement of foundation and pier at plastic hinge location
Figure (40). Some detailed drawings of the underpasses represents the drainage and waterproofing system.
Figure (46) Some of the detailed drawings of the overpass. A) Reinforcement of the box in mid-span. B) Reinforcement of foundation and pier at plastic hinge location
Figure (40). Some detailed drawings of the underpasses represents the drainage and waterproofing system.