Geotextile wrapped steep dams on soft soils are earthquake resistant and durable. The dam will be earthquake resistant and durable if the dam is designed keeping in view the changes in the dynamic properties of different levels of the dam during an earthquake or wave (sinusoidal).
This was stated by the speakers at the seminar titled ‘Application of Wrap Face Embankment on Soft Soil of Bangladesh’ organized by the Civil Engineering Department of Institution of Engineers, Bangladesh (IEB) on Tuesday (September 28) afternoon.
IEB Civil Engineering Department Chairman Prof. Engineer Munaj Ahmed Noor presided over the function while the function was anchored by Engineer Amit Kumar Chakraborty, Secretary of the same Department. Engineer Md. Abdus Sabur, former President of the Institution of Engineers, Bangladesh (IEB) was present as the Chief Guest.
As a special guests, the President of the Institution of Engineers, Bangladesh (IEB), Engineer Md. Nurul Huda, IEB Vice President (HRD) Engineer Nuruzzaman and LGED Chief Engineer Abdur Rashid Khan were present in the program.
IEB Honorary General Secretary Engineer Shahadat Hossain (Shiblu) delivered the welcome speech. Engineer Ripon Hod, LGED senior assistant engineer presented the main article at the seminar. BUET Professor of Civil Engineering, Engineer Mehedi Ahmed Ansari discussed on the main article. The vice-chairman of the department, Engineer Zikrul Hasan thanked the participants present on the occasion.
Speakers at the seminar said the wrapped dam is paved with different geotextiles and is filled with sand of different properties (cement sand or local sand). As the dam is steep, it will not be necessary to acquire agricultural land on both sides as compared to the conventional dam. Two types of ovens or non-oven geotextiles are used in the construction of the dam. The wrapping dam is made up of different layers depending on the relative location, geographical location and EGL of the soft soil properties.
The speakers also said that the dynamic properties of dams built on soft soil during earthquakes or different waves should be analyzed and such dams should be constructed which will be earthquake resistant. As well as being built at a lower cost than conventional dams and it will require less space to build.
The speakers also said that the wrapped dam would reduce the cost of land acquisition by the government. Since the dam is steep, space on both sides will not be required. For example, a wrapped dam will reduce the cost by 70% compared to a conventional dam. It can be said that 1 crore 86 lakh taka will be required for the construction of the dam, which would have cost 4 crore 30 lakh taka for the construction of the conventional dam, including the cost of land acquisition. Extensive agricultural land should not be used for road construction. Agricultural produce will be produced in these agricultural lands.
The dam will be climate tolerant which means it will be able to withstand floods and cyclones. Due to the dam being wrapped by geotextiles and developing friction with the sand as well as being internally interlocked, it will be able to withstand the effects of floods and cyclones more than conventional dams.
