The valorization of Senegalese attapulgite clay in concrete, as a solution against the exhaustion of the cement deposits was studied. In that purpose, attapulgite was first calcined at 800°C to make it reactive a...The valorization of Senegalese attapulgite clay in concrete, as a solution against the exhaustion of the cement deposits was studied. In that purpose, attapulgite was first calcined at 800°C to make it reactive and added in concrete by substitution of Portland cement (CEM I 52.5N) at contents of 0, 5 and 10% by conserving a constant water/cement ratio value of 0.65. The effects of the partial replacement of cement by attapulgite on the physicochemical and mechanical properties of the concrete as well as on the steel-concrete bond were examined. For this purpose, the water porosity, the intrinsic permeability and the density of the clay-based concrete were evaluated. Compression, tensile and pull-out tests were carried out to determine the impact of clay on the Young modulus, the compressive and tensile strengths and the steel-concrete bond. This study was completed by a characterization of the pozzolanic reactivity of calcined attapulgite. All the results of these studies were compared with those of Portland cement as a reference. The substitution of cement by attapulgite up to 10% in concrete has only a small influence on its porosity and permeability and confers to the concrete gain in compressive strength of 11%. However, it caused a loss of steel-concrete bond of 10%.展开更多
China has further cut and eliminated tax rebates on thousands of export items in order to curb its ballooning trade surplus The Chinese Government made its
The Chinese Government is intensifying efforts to curb breakneck economic growth Beijing is feeling mounting pressure from China's runaway economy, which grew 10.9 percent in the first half of this year. On July 2...The Chinese Government is intensifying efforts to curb breakneck economic growth Beijing is feeling mounting pressure from China's runaway economy, which grew 10.9 percent in the first half of this year. On July 21 and 26, the Central Government summoned two high-level meetings to chart a course for the country's展开更多
Law furthers administration system On June 30,the Standing Committee of the 11th National People’s Congress(NPC),China’s top legislature,adopted the Law on Administrative Coercion at its 21st meeting."The law s...Law furthers administration system On June 30,the Standing Committee of the 11th National People’s Congress(NPC),China’s top legislature,adopted the Law on Administrative Coercion at its 21st meeting."The law stipulates specific展开更多
Concerned about the effects of increasing water scarcity on economic development, China hopes a new law will save the Yellow River The first day of August marked what could be a new page in the history of China's ...Concerned about the effects of increasing water scarcity on economic development, China hopes a new law will save the Yellow River The first day of August marked what could be a new page in the history of China's long-suffering "mother river." That day, a regulation took effect that for the first time in histo-展开更多
The painful reforms chosen by French voters to rejuvenate their sluggish economy have smoothed the way for Nicolas Sarkozy to take up France’s top political job.The 52-year-old leader of the ruling right-wing
文摘The valorization of Senegalese attapulgite clay in concrete, as a solution against the exhaustion of the cement deposits was studied. In that purpose, attapulgite was first calcined at 800°C to make it reactive and added in concrete by substitution of Portland cement (CEM I 52.5N) at contents of 0, 5 and 10% by conserving a constant water/cement ratio value of 0.65. The effects of the partial replacement of cement by attapulgite on the physicochemical and mechanical properties of the concrete as well as on the steel-concrete bond were examined. For this purpose, the water porosity, the intrinsic permeability and the density of the clay-based concrete were evaluated. Compression, tensile and pull-out tests were carried out to determine the impact of clay on the Young modulus, the compressive and tensile strengths and the steel-concrete bond. This study was completed by a characterization of the pozzolanic reactivity of calcined attapulgite. All the results of these studies were compared with those of Portland cement as a reference. The substitution of cement by attapulgite up to 10% in concrete has only a small influence on its porosity and permeability and confers to the concrete gain in compressive strength of 11%. However, it caused a loss of steel-concrete bond of 10%.
文摘China has further cut and eliminated tax rebates on thousands of export items in order to curb its ballooning trade surplus The Chinese Government made its
文摘The Chinese Government is intensifying efforts to curb breakneck economic growth Beijing is feeling mounting pressure from China's runaway economy, which grew 10.9 percent in the first half of this year. On July 21 and 26, the Central Government summoned two high-level meetings to chart a course for the country's
文摘Law furthers administration system On June 30,the Standing Committee of the 11th National People’s Congress(NPC),China’s top legislature,adopted the Law on Administrative Coercion at its 21st meeting."The law stipulates specific
文摘Concerned about the effects of increasing water scarcity on economic development, China hopes a new law will save the Yellow River The first day of August marked what could be a new page in the history of China's long-suffering "mother river." That day, a regulation took effect that for the first time in histo-
文摘The painful reforms chosen by French voters to rejuvenate their sluggish economy have smoothed the way for Nicolas Sarkozy to take up France’s top political job.The 52-year-old leader of the ruling right-wing
