The expansion of the Hammond Drive bridge over Georgia Highway 400 will help alleviate traffic in the busy area north of the city.
Metro Atlanta motorists may face a hassle in the near term, but in the long term, the expansion of the Hammond Drive bridge over Georgia Highway 400 will help alleviate traffic in the busy area north of the city.
Earth began to be moved in the late spring on the $17 million design-build project, located several miles north of downtown Atlanta in the busy corridor between I-285 and Abernathy Road in the suburban city of Sandy Springs. The target date for completion is set for Aug. 31, 2011.
According to Mickey McGee, the Metro Atlanta construction engineer for the Georgia DOT, the project entails expanding the Hammond Drive overpass at state Road 400 from a four-lane to a nine-lane bridge, including two turning lanes at each end of the overpass. A raised median on the bridge will separate the east- and west-bound lanes of Hammond Drive.
“When work is finished, we will have a much wider and longer bridge to accommodate any future expansion of the lanes on Georgia 400, as well as a half-diamond interchange,” McGee said. “That half-diamond will include a southbound off ramp and a northbound on ramp, with those auxiliary lanes extending up Georgia 400 to the next interchange at Abernathy Road.”
McGee hopes that the new Hammond Drive half-diamond interchange and bridge will help drivers move more easily through a historically congested area.
“Certainly this project is designed to funnel some of the traffic that normally would use Abernathy Road and/or I-285 toward Sandy Springs and/or the Dunwoody-Perimeter Center area,” he added.
With work underway, traffic has been disrupted along both Hammond Drive and Georgia 400, mainly though traffic lane shifting, McGee said.
The contract for building the interchange and expanding the 1000-ft. (304.8 m)-long bridge was awarded to Marietta-based C.W. Matthews Contracting Co.
By the end of June, C.W. Matthews and its main subcontractor, the Marietta office of Schnabel Foundation, had reached the point where they were hard at work erecting retaining walls at the Hammond Drive overpass. Schnabel is responsible for the soldier piles and lagging at the bridge.
“Primarily we have been installing tie-back retaining walls on each side of SR 400 in front of the abutment of the new bridge,” explained George Ploetz, construction manager on the project for C.W. Matthews. “We have poured the abutments on either side for the first stage of the bridge and we are working on the substructure on one of the piers. Really, we have been doing a little bit of drainage work and a little bit of dirt work so far.”
C.W. Matthews also is working on improving the approaches to the bridge on Hammond Drive.
Ploetz said about 30 to 35 workers are at the project site at any one time right now. The crew is currently using a Link- Belt LS 318, a 110-ton (100 t) crane, as well as an American 5300, an 85-ton (77 t) crane. Additionally, there are a number of Komatsu and Caterpillar excavators and tractors working on the project, as well.
All of the pieces are owned by C.W. Matthews, Ploetz said.
Crews removed a portion of the existing median barrier on Georgia 400 in order to construct the intermediate bridge piers. In addition, an earthen berm is being built and stabilized adjacent to the northbound lanes of state Road 400, which is needed before sound barriers can be installed along the highway’s east side to protect the nearby Dunwoody Springs neighborhoods.
“Once we get the two center piers built we will put the beams up and build the bridge,” Ploetz explained. “The span is going from 220 feet to about 400 feet wide and that is because we are adding the capacity for extra lanes, or express lanes. The two spans coming off the abutment are fairly long at 160 to 170 feet.
“We are starting to face the lagging walls — we have a concrete facing on them and they are in excess of 30 feet high,” he added. “Actually, we are building them really deep and then we are going to fill dirt back into the face of them so when the Georgia DOT wants to come in with future lanes on state Road 400, everything will be in place.”
Ploetz figures that work will have progressed enough by the end of the year that traffic will be able to move over one half of the new section of the Hammond Drive bridge. At that point, he said, most of the excavation at the interchange will be completed.
Besides the work being done by Schnabel Foundation, most of the rest of the work is being done by C.W. Matthews itself, including the future asphalt work over the bridge and along the auxiliary traffic lanes. CEG