Use of Supplementary Cementitious Materials at the McMurtry Building

This project involved consultation for the production of sustainable, architectural, white concrete for the construction of the McMurtry Building at Rice University in Houston, Texas. The many challenges associated with the architectural and structural concrete included the use of seventy percent cement replacement with slag as a supplementary cementitious material while achieving adequate strength gain during early ages to meet the demands of the construction activities. CA developed recommendations on the selection of the concrete materials and the concrete mixture proportions, guidelines for the batching and mixing of the concrete, formwork details, form release agents, and concrete consolidation procedures. The final selection was based on the casting of several mockups. Other issues addressed included recommendations for the protection of the architectural concrete during other construction activities such as acid wash of the CMU installations.

LEED Certification at LCRA Red Bud Center

CA provided sustainable construction consulting services to the general contractor for the construction of the LCRA Red Bud Center’s architectural concrete elements including textured exposed architectural concrete walls. CA’s consulting work included the review and evaluation of the concrete specifications, plans, and drawings.  CA then developed recommendations for the concrete mixture proportions, formwork, and concrete placement, in particular consolidation practices to meet the project requirements and most importantly the architect’s vision and aesthetic value of the exposed concrete. The architecturally exposed concrete walls were required to exhibit a textured form finished pattern and appearance similar to that observed in the Tom Miller Dam adjacent to the LCRA Red Bud Center built over 60 years ago. CA was also involved in the evaluation and concrete repair of the finished concrete walls. The design requirements incorporated the implementation of sustainable construction strategies and practices required to meet the standards of the United States Green Building Council. The facility achieved USGBC LEED® Gold Certification and Four-Star Rating from the Austin Energy Green Building Program.

Sustainable Construction: Utilization of Coal Combustion By-Products

CA was retained by AES Puerto Rico to work on developing and evaluating alternatives for the utilization of coal combustion by-products from the production of electricity by AES in their plant in Guayama, Puerto Rico. Among the many alternatives developed, the use of the by-product for producing unbound granular fill and base material for highway construction and in flowable fill applications in construction were found to be promising. CA performed materials characterization as well as trial mixes and mock-up placements for this application. The evaluation and analysis of the strength development properties and chemical and mineralogical examination of samples at different ages and different exposure conditions was done in collaboration with Texas A&M University. Of great importance in this materials research project was the development of the necessary guidelines for ensuring the dimensional stability of the material while in service.