Trial mix programme for Jahgm Dam - the first major RCC dam in Iran

Jahgin Dam, which is presently under construction in Southern Iran, will be the first major RCC dam in the country. The dam is located in an area of very high temperatures, in summer the maximum temperature exceeds 50degreesC. One of the factors that has limited the development of RCC dams in Iran has been the lack of a low-lime flyash in the country. Before the commencement of the trial mix programme for Jahgin a search was made for locally-available pozzolans so that the performance of these in an RCC could be compared with that of a low-lime flyash that was being imported into Iran from India. Four different pozzolans were located in Southern Iran; a natural pozzolan from Khash in the south-east of the country, a ground blast-furnace slag from Esfahan, a ground copper slag from Kerman and a second natural pozzolan from Sirjan. The paper describes the first Stage of the trial mix programme in detail and the selection of the most suitable pozzolans that were tested in the second-Stage trial mix programme. The full-scale trial is also briefly described as is the start of placement of RCC in the cofferdam.