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 and providing access to the newly developed Meridiana Development. Coordination with TXDOT, area landowners, utility companies, and Brazoria County was integral in obtaining approval and acceptance of the project. The main design challenge for this project was to accommodate double intersections on the west side of SH 288 to tie into existing access roads with two-way traffic and a new southbound on-ramp within a close proximity. EHRA coordinated with TxDOT throughout the project from preliminary concepts for the intersection and bridge through final design and construction. Each component of this project was designed in accordance with TxDOT standards and criteria.
EHRA completed preliminary engineering, phase one environmental site assessment and schematic development for the widening of Northpark Dr. between US 59 and Woodland Hills Dr. EHRA also provided program management, drainage analysis and design, traffic engineering, environmental documentation and schematic design for the roadway, as well as grade separation at the Loop 494/UPRR railroad crossing.
EHRA conducted traffic operations and access management studies for the Northpark Dr. corridor. This corridor is approximately 2.2 miles long and has major signalized and unsignalized intersections and driveways that access various subdivisions and industrial developments. These studies laid the groundwork for the widening of Northpark Dr. from a four-lane boulevard cross-section to a six-lane boulevard complete street. The new street design includes low impact development drainage, conventional drainage, a grade separation at the UPRR crossing with mechanically stabilized earth retaining walls, two at-grade crossings for bi-directional frontage access, reconstruction of two concrete bridges over a diversion channel, intersection improvements, a roadway-adjacent multiuse path and traffic signal improvements.
Drainage analysis and design included hydrologic and hydraulic studies of both existing and proposed conditions to demonstrate that proposed project components would not adversely affect the 100-year floodplain in the area. The roadway and traffic designs contained horizontal and vertical alignments, cross-sections, plan and profile, sidewalk and bicycle accommodations, intersection layouts, traffic control plans and signing and pavement markings.
As the program management firm, EHRA coordinated with TxDOT, UPRR, the City of Houston Council District E, COH Planning and Development Department, COH Public Works and Engineering Department, Montgomery County, Harris County, HCFCD and area residents throughout the project.
In 2006, Caldwell Companies sought to create Towne Lake as a community where residents and services could be connected by water. Their vision included boat docks and marinas augmenting traditional walking trails to navigate a vibrant residential community. EHRA was the perfect partner to take Caldwell Companies’ vision and create this livable suburban oasis.
EHRA worked with the District to create a comprehensive Parks Master Plan, which included recommendations for the development of over two miles of hike/bike trails adjacent to local streets, and within flood control and utility pipeline easements. The District began implementation of the Plan by prioritizing the beautification of West Road, a major arterial street that runs through the District.
What do sea urchins and cement have in common? More than you'd think! The sea urchin spines are mostly made of calcite, usually a very brittle and fragile material. In the case of the sea urchin, however, the spines are much more durable than the raw material alone. The reason for its strength is the way that nature optimises materials using a brick wall-style architecture. The research team Physical Chemistry, headed by Professor Helmut Cölfen, successfully synthesised cement at the nano-level according to this "brick and mortar principle." During this process, macro-molecules were identified that take on the function of mortar, affixing the crystalline blocks to each other on the nano-scale, with the blocks assembling themselves in an ordered manner. The aim is to make cement more durable.
In nanoscience, brick wall-style architecture can be compared to the work of a mason: each layer of brick that is laid is held in place by mortar. The guiding principle is to layer hard, then soft, hard, then soft materials. This is exactly the principle nature uses to make sea urchin spines so resilient. When force is applied to the brittle calcite, its crystalline block does crack, however, the energy is then transferred to a soft disordered layer. Since this material has no cleavage planes to tear, it prevents further cracking. A thin section of sea urchin spine reveals this structural principle: crystalline blocks in an orderly structure are surrounded by a softer amorphous area. In the sea urchin's case, this material is calcium carbonate.
In collaboration with the University of Stuttgart, the research team was able to use an ion beam under an electron microscope to cut a bar-shaped micro-structure out of the nanostructured cement that was three micrometers in size. This micro-structure was then bent using a micro-manipulator. As soon as it was released, the micro-structure returned to its original position. Mechanical values could be calculated based on the elastic deformation of the micro-structure. Based on these calculations, the optimised cement achieved a value of 200 megapascals. By comparison: Mussel shells, which are the gold standard in fracture-resistance, reach a value of 210 megapascals, which is only slightly higher. The concrete commonly used today has a value of two to five megapascals.
See urchin spines and mussel shells are made of calcite, because large quantities of calcium are available in water. Helmut Cölfen explains: "People have much better construction materials than calcite. If we succeed in designing the structures of materials and reproduce nature's blueprints, we will also be able to produce much more fracture-resistant materials -- high-performance materials inspired by nature."
Source: University of Konstanz