Presseberichte

Indian Institute of Technology Earthquake Research Provides Benchmark for STAAD.Pro Analysis Accuracy

The Indian Institute of Technology in Rorkee, India, which is studying the affects of earthquakes on multi-story buildings, has released research findings that used data gathered from last year's devastating Gujarat earthquake in western India to benchmark the results modeled by STAAD.Pro structural analysis and design software. The research carried out by IIT verified and confirmed the accuracy of STAAD.Pro's advanced dynamic analysis of structures modeled to determine the affects of earthquakes. The highly regarded academic institution, equivalent to Massachusetts Institute of Technology and California Institute of Technology in the U.S., is conducting ongoing research through its Department of Earthquake Engineering, which places earthquake sensors in a number of buildings throughout India to record data. IIT's instrumentation recorded a significant amount of data from January 26, 1002 Gujarat earthquake that measured 6.9 in the Richter scale. "The data gathered by researchers and used as a benchmark to compare results obtained by STAAD.Pro's structural analysis contributes to a growing body of knowledge about how to design and build safer buildings able to withstand earthquakes," said Santanu Das, Vice President, Technology Strategy for netGuru, Inc. (NASDAQ: NGRU). Research Engineers International, a division of netGuru, Inc., is the developer of STAAD.Pro structural analysis and design software.

Among the structures in which IIT researchers placed sensors was a 10-story residential building which served as staff quarters of the Regional Passport Office Building in Ahmedabad, state capital and closest major city to the epicenter of the Gujarat earthquake. The instrumentation, comprising 14 force balance accelerometers placed throughout the building, recorded data form main shock and one aftershock. Tri-axial and uniaxial sensors were installed on the ground floor, top floor and near the beam-column joint below the slab of each floor. Fourteen acceleration time histories of 133.53 seconds duration at 200 samples per second were recorded by these locations. According to the IIT, this is the first time in India that an instrumented building has yielded such data during an earthquake. Using STAAD.Pro, IIT researchers created a 3-D space frame model of the steel and concrete building using available structural drawings. The mathematical model included plan, elevation and isometric views of the structure. The space frame model comprised 799 nodes out of which 67 nodes were fixed nodes at the base, 1.572 beam elements and 219 plane stress slab elements. The researchers made a number of assumptions in the mathematical model, taking into account stiffness and mass of walls, various stress elements, thickness of truss elements, dead loads, live loads and elastic behavior of the building among other variables.

For seismic engineers, an earthquake is an event that gives them the opportunity to learn more about the seismic response of man-made structures, with the objective to record their seismic response, is one of the most effective ways of determining the feedback on performance of structures during an earthquake. As some very critical data on different floors of the building was recorded during the main shock and first aftershock of the Gujarat earthquake, it provided researchers with an opportunity to compare the results of STAAD.Pro's analytical tools with the recorded response of the building. With the recorded data as a benchmark, a dynamic analysis was performed to compare the recorded data with results obtained by using the software to analyze the building's vibrational characteristics as well as response at different locations of the structure. The IIT comparison of the recorded data and the results of the STAAD.Pro analysis of the model yielded similar responses, according to the recently released research study. While IIT researchers concluded that the analytical results of the STAAD.Pro model generally matched well with the measured data of the building, they cautioned that more research is needed to adequately arrive at useful conclusions that may benefit the design and construction industry. "We are certainly pleased with the finding of IIT's study," Das commented. "The research has resulted in a number of improvements to STAAD.Pro 2002. These refinements are part of our ongoing effort to provide the most useful and accurate structural analysis and design software tools for engineers."

Funding for IIT's ongoing earthquake research project is provided from the World Bank through the Government of India's Department of Science and Technology, which has supported the research of IIT over the past 25 years.
The earthquake that shook the Indian state of Gujarat on the morning of January 26, 2001, India's Republic Day, was one of the two most deadly earthquakes to strike the country in its recorded history. The official Government of India figures placed the death toll at approximately 20.000 and the number of injured at 166.000. Indications are that 600.000 people were left homeless, with 348.000 houses destroyed and an additional 844.000 damaged. The Indian State Department estimated that the earthquake affected, directly or directly, 15.0 million people out of a total population of 37.8 million in the state of Gujarat. Some estimates placed direct economic losses at $1.3 billion, with other estimates indicating losses as high as $5 billion.

Bauingenieur - Die richtungsweisende Zeitschrift im Bauingenieurwesen (Juli/August 2003)