X-RAY MICRO-TOMOGRAPHY CHARACTERIZATION OF VOIDS CAUSED BY THREE-POINT BENDING IN SELECTED ALKALI-ACTIVATED ALUMINOSILICATE COMPOSITE

This paper deals with the pilot characterization of a special alkali-activated aluminosilicate composite composed of waste brick powder, brick rubble and a solution of potassium water glass. Fracture tests were conducted on the specimens via three-point bending and fracture parameters were evaluated. Selected specimen was investigated using micro-tomography to supplement the results with visual information about the inner structure of this newly designed material before and after the mechanical loading. Tomographic measurements and image processing were conducted for a qualitative and quantitative assessment of changes in the internal structure with an emphasis on the calculation of porosimetric parameters and visualization of the fracture surface. Fractal dimension of fracture surface was estimated.

Archeological Investigations for the Levi Jordan Plantation House Stabilization, Brazoria County, Texas

The Levi Jordan plantation house is one of the few antebellum plantation structures to have survived in Brazoria County. It is the only standing structure associated with the plantation, which began operating in 1848 and was occupied continually up through the 1990s. The original house, built in the early 1850s using slave labor, was a 20x60-ft two-story wooden frame structure. It was altered many times during its long occupation, often due to hurricane damage. A portion of the Levi Jordan Plantation was acquired by the State of Texas in 2002 and managed by the Texas Parks and Wildlife Department until 2008, when the Texas Historical Commission took over its management. By then, the 160-year-old plantation house had suffered greatly and was in bad condition. The Texas Historical Commission began plans to stabilize and restore the historic house. Prewitt and Associates archeologists were contracted to conduct the archeological investigations associated with this work. The stabilization project included the permanent removal of the twentieth-century additions, hydraulic lifting of the antebellum house, removal of the original foundation piers, and installation of a new concrete perimeter foundation. The two original brick chimneys were removed and reconstructed. The investigations, conducted in 2010 and 2011, documented the following features: 2 cisterns, 2 chimney footings and 39 foundation piers associated with the plantation house; a chimney footing associated with an east wing behind the house; a chimney foundation associated with a former detached kitchen behind the main house; a brick patio and walkway associated with the original house; two large brick rubble concentrations and a small brick cluster; and a possible rain barrel brick pad. Other features examined were 15 possible piers that may be associated with the original house, the original east wing, a possible west wing, a south porch, a west porch, and an east porch. The archeological investigations revealed many details about the architecture of the original plantation house and subsequent additions. The evidence provides a better understanding of the building construction sequence and insights into the complex evolution of the Levi Jordan plantation house over its ca. 160-year existence. The most significant find is an 1853 gold coin found in the brick pad at the bottom of the southeast corner pier. This is almost certainly a date coin that was placed in this location by Levi Jordan or a master builder in a cornerstone foundation rite, and it provides an accurate date for the beginning of the house construction.

Treatment of a molasses based distillery effluent in a constructed wetland in central India

A field-scale 4-celled, horizontal subsurface constructed wetland (CW) was installed to evaluate removal efficiencies of wastewater constituents in an industrial distillery effluent. Total and dissolved solids, NH4-N, TKN, P and COD were measured. This CW design provides four serial cells with synthetic liners and a river gravel base. The first two unplanted cells provide preliminary treatment. Specific gravel depths and ensuing biofilm growth provides anaerobic treatment in Cell 1 and anaerobic treatment in Cell 2. Cell 3 was planted with Typha latifolia with an inserted layer of brick rubble (for phosphorus removal). Locally grown reed, Phragmites karka was planted in Cell 4. COD was reduced from 8420 mg/l 3000 from Cell 1 to the outlet of Cell 4. Likewise other parameters: total and dissolved solids, ammonium and total nitrogen, and total P, indicated declining trends at the 4-celled CW effluent. This study reveals how high strength distillery wastewater strongly impacts morphology, aeration anatomy in the chiseled plant tissues, reed growth; and composition of the biofilm in the specialized substratum. The reliability of a CW for organic and nutrients reduction, in association with a poorly performing conventional system is discussed. There is an immense potential for appropriately designed constructed wetlands to improve high strength wastewaters in India.