May 2017 Vol. 72 No. 5
Features
CIGMAT 2017 Highlights Challenges, Changes
The University of Houston’s Center for Innovative Grouting Materials and Technology (CIGMAT), and the Department of Civil and Environmental Engineering organized and hosted its 22nd annual conference and exhibition at the college on March 3. Titled “Infrastructure, Energy, Geotechnical, Flooding and Sustainable Issues Related to Houston & Other Major Cities,” the one-day event attracted more than 300 participants with 14 speakers that represented owners, consulting engineers, material suppliers, contractors and academia.
In his welcome remarks, Dr. Vipu, director of CIGMAT and the Texas Hurricane Center for Innovative Technology (THC-IT), emphasized the need for such a conference in the energy capital of the United States, especially during these challenging times of ever-increasing need for complex infrastructure maintenance, energy demand and technology advances to meet population growth and industrial expansion.
The morning’s general session helped set the stage by focusing on energy needs around the world, public works and highway transportation infrastructures. Dale Rudick, director of public works and engineering department at the city of Houston presented the plans for maintaining and expanding water, wastewater and other infrastructure facilities in a sustainable manner. He also addressed issues related to maintaining public transportation facilities, parks and streets, and increased community participation in some of the decision-making processes.
Bill Brudnick, director of planning at the Texas department of transportation, reviewed several ongoing and new highway projects valued at over several billion dollars that will start in the next few years, as well as issues regarding maintenance and funding for the department. Jason Pettrey, department head for ExxonMobil’s Beaumont Refinery, discussed current and future needs for energy − oil and gas, and alternative energy production − around the world. He explained that increased energy needs are not only due to growth of industries, but also growth of the middle-class population, especially in Asia.
Flooding, maintenance, construction issues
In the first of four technical sessions, a panel discussion on “Flooding, Maintenance and Construction Issues,” Russell Poppe, director of Harris County flood control, covered flood control projects, including plans for developing detention ponds, and their benefits to the community. This balancing act is a continual challenge in the third-most-populous county in the United States, and achieving needed flood risk reduction.
Rod Pinheiro, assistant director, street and drainage division in Houston, discussed the storm water action team (SWAT) programs. Records indicate that numerous areas are experiencing flooding not directly subject to riverine/bayou overbank flooding. These flood-prone areas are generally located in older parts of the City (developed prior to 1985) and have either inadequate and/or undersized infrastructure. In January 2017, Houston’s mayor recommended that an ordinance of $10 million to fund projects related to SWAT programs be approved in an effort to reduce the localized non-riverine drainage problems.
SWAT’s goal is to expand maintenance capabilities in order to improve the conveyance of day-to-day storm events through rehab and/or upgrades to the existing drainage infrastructure. The work encompasses everything from replacing storm sewer and outfall pipes, regrading of ditches, replacing culverts not set to the proper flowline, clearing and grubbing, repairing minor erosion problems, and mowing. Daniel Gossett, from Mason Construction, presented the major issues related to construction and maintenance of industrial plants in Houston and along the Texas coast. The session was moderated by Rafael Ortega, of Aurora Technical Services, Houston, TX.
Transportation, industrial construction issues
The second technical session, “Transportation and Industrial Construction Issues,” began with John Tyler, deputy director of Harris County Toll Road Authority (HCTRA), reviewing authority Capital Improvement Projects (CIPs).
Shawn McGraw and Silky Wong, engineers from Fluor, discussed the differences in engineering contracts for industrial, versus residential and commercial, oil and gas facilities. Because they involve large capital costs, large and complex equipment, job sites in harsh environments, and economic viability heavily subjected to government funding, permits and environmental regulations, industrial contracts typically require multi-staged estimating and planning throughout the engineering time period. In response to changes in crude pricing that led to lower profitability, industrial oil and gas engineering must evolve to new execution, construction and design techniques that reduce costs for clients and make projects viable.
Water, wastewater issues
In the third technical session, Eric Wessels, co-program manager at San Antonio Water System (SAWS), TX, discussed “Water and Wastewater Issues.” As the seventh-largest city in the nation, San Antonio has 350 miles of large-diameter pipes, 4,850 miles of small-diameter pipes, 100,000 manholes, 300 siphons, 80 miles of force mains, 156 lift stations and three treatment plants.
According to the 2013 Consent Decree (CD) with TCEQ, EPA and the Department of Justice, SAWS was required to perform both capacity and condition assessments over the next four years to help identify “high-risk pipe” − areas within the system that have caused or significantly contributed to previous SSOs, and/or are likely to cause or significantly contribute to the future occurrence of SSOs.
Via closed circuit television and pole camera, SAWS assessed and rated each pipe “A-E,” with “E” being very poor. The CD required SAWS to address all “E” pipe in the Remedial Measures Plan. SAWS completed the capacity assessment using data obtained from flow meters, field verifications and evaluation of the system’s hydraulic model. All confirmed capacity constraints (where the pipe is not large enough to carry flows without surcharging) must be addressed in the Remedial Measures Plan.
SAWS is required to submit the results in a Condition and Capacity Assessment Report to the EPA in January 2018. One year later, SAWS must submit the Remedial Measures Plans for both condition and capacity. These plans will include a listing of all assets in each project, the remedial measure selected and the timeframe to complete the project, and will commit SAWS to build the identified projects, without changes, by 2023.
Also during the session, Alan Andrews, hydrologist from the Texas Water Development Board (TWDB), reviewed the agency’s 2017 State Water Plan, particularly as it pertains to Innovative Water Technologies programs. The TWDB mission is to provide leadership, information, education and support for planning, financial assistance and outreach related to the conservation and responsible development of water in the state. Yvonne Forrest, senior assistant director at the city of Houston, discussed the infrastructure and its impact on water quality. The third technical session was moderated by Michael Lacy, KIT Professional Inc., Houston.
Expansive clays, smart cement
For the fourth technical session, Kenneth E. Tand, practicing geotechnical engineer, delivered the 12th Mike O’Neill Lecture on “Effects of Vegetation on Foundations Bearing in Expansive Clays in Urban Environment.” Recognized as one of nine hazards causing building distress in North America, expansive clays are estimated to cause annual damages costing $15 billion dollars.
Tand has performed more than 50 geotechnical forensic studies for sites in Texas with damages due to expansive clays, with most occurring in the greater Houston area. The studies were specific to commercial buildings supported on under-reamed piers or spread footings, and showed that the cause of building distress at more than one-half of the sites was the presence of trees next to the buildings. Removal of pre-existing trees or thick underbrush prior to construction at one-quarter of the sites was another major contributing factor to building distress.
Next, Dr. Vipu delivered a presentation on “Smart Cement Composites Characterization and Corrosion Detection and Quantification Using Real-Time Monitoring Systems: Development and Modeling.” Smart cement composites containing highly sensing chemo-thermo-piezoresistive properties with enhanced physical and mechanical properties, have been developed and characterized to meet various application requirements with real-time monitoring. In this study, smart cement was modified with foam, iron nano particles and aggregates.
The corrosion of steel was directional and with current monitoring approach, the bulk and surface corrosion of the steel was quantified in terms of electrical resistivity and a new interface coupling parameter respectively. The directional resistivity changes during corrosion were much higher than the weight change and pulse velocity change. The Vipulanandan p-q curing, stress-strain and piezoresistive models predicated the experimental results very well. Also, the Vipulanandan impedance-frequency model predicted both the smart cement composites and steel corrosion behaviors.
After the technical sessions, participants attended a reception in the exhibit area, where posters on research activities at CIGMAT and the University of Houston Department of Civil and Environmental Engineering were on display. A number of grouting, pipe manufacturers, material suppliers, pipe condition monitoring and wastewater rehabilitation companies also contributed to the exhibit.
The conference proceeding is posted on the CIGMAT website (http://cigmat.cive.uh.edu). CIGMAT 2018 will be held on March 2, 2018, at the University Hilton located on the University of Houston’s main campus.
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