Engineering design and construction phase services of water, sewer, drainage and paving for four subdivision sections and off-site channel (123 acres out of a 400 acre subdivision). There was 60-feet of elevation difference on this site and wooded lots were left in their natural state which required the installation of retaining walls.
Identified as a top priority during the development of the District’s Parks Master Plan, this portion of trail was the first phase of over two miles of planned trails to provide connectivity and recreation for District residents.
The purpose of this project was to convert the existing at-grade crossing of Brazoria County Road 56 (CR 56) and State Highway 288 (SH 288) into a diamond interchange that includes a new overpass bridge. Coordination with TXDOT, area landowners, utility companies, and Brazoria County was integral in obtaining approval and acceptance of the project.
EHRA completed a site-specific planning and visioning study for the proposed 470-acre San Jacinto Boulevard District (SJBD) in Baytown, Texas.
EHRA planners, hydrologists and landscape architects worked together to propose an alternative use for the space, re-developing the basin into an amenity pond. EHRA carefully selected native plant materials for both their ability to survive in the harsh conditions of the basin as well as providing filtration for improved storm water quality.
The dangerous wobbling of pedestrian bridges could be reduced by using biomechanically inspired models of pedestrian response to bridge motion and a mathematical formula to estimate the critical crowd size at which bridge wobbling begins, according to a study led by Georgia State University. Many pedestrian bridges around the world have experienced dramatic vibrations and dangerous wobbling when crowds of pedestrians have tried to cross them, with some bridges falling down. Bridges all over the world have experienced this including the Squibb Park Bridge in Brooklyn that remained closed for years after wobbling.
"In this Science Advances paper, we reveal this threshold effect and show this is a general phenomenon for bridges," said Dr. Igor Belykh, professor in the Department of Mathematics and Statistics at Georgia State. "We challenge the widespread view that increasing the crowd size will gradually increase the bridge wobble. The current view is the more pedestrians we add to the bridge, the wilder the oscillations will be. This is true, but only for crowd sizes above this critical size. There is an important threshold effect.
"Our paper gives an explicit guideline and formula of how to estimate this critical crowd size, which can be used to limit the carrying capacity of an existing bridge and to help designers build better bridges. The biomechanical models we're developing are particularly important for understanding the role of crowd dynamics on a wobbly bridge because the U.S. code for designing pedestrian bridges does not contain specific guidelines that account for collective pedestrian behavior. The industry standard programs used by bridge designers only use linear models. We're working on the inclusion of biomechanical models like ours into the standard tools and software programs used by bridge designers to better predict the nonlinear effects associated with the interaction between crowds of pedestrians and bridges."
In 2014, the Squibb Park Bridge in Brooklyn, N.Y. bounced from side to side as pedestrians crossed the bridge and didn't reopen until early 2017.