洛河流域安山玢岩碱骨料反应试验研究

Experimental Study on Alkali Aggregate Reaction of Andesitic Porphyrite in Luohe River Basin

碱骨料反应是影响水工混凝土耐久性的重要因素之一.分别采用砂浆棒快速法和碳酸盐骨料碱活性检验法对洛河流域安山玢岩骨料碱活性进行试验研究.采用砂浆棒快速法,取3组安山玢岩骨料试件进行碱活性试验,分析安山玢岩骨料在3,7,14,28 d 4个不同龄期的膨胀率变化,试验结果未能确定安山玢岩骨料碱活性,需采用碳酸盐骨料碱活性检验法进一步试验研究;采用碳酸盐骨料碱活性检验法,取18组安山玢岩骨料试件进行碱活性试验,并分析安山玢岩骨料在3,7,14,28,56,84 d 6个不同龄期的膨胀率变化,编号X-6组试件和编号Z-5组试件84 d龄期的膨胀率均大于0.1%,依据《水工混凝土试验规程》(SL 352—2006)判定,洛河流域安山玢岩骨料具有潜在碱活性.综上试验结果表明,洛河流域安山玢岩具有一定的潜在碱活性危害.

Alkali aggregate reaction is one of the important influencing factors on the hydraulic concrete durability. Using the accelerated mortar bar method and carbonate method,the expansion rates of andesitic porphyrite in Luohe river basin in different ages were studied. Accelerated mortar bar method studied the expansion rates through 3 d,7 d,14 d,28 d of the four different ages swell,the results failed to identify andesitic porphyrite aggregate alkali activity and carbonate method was used to test further. Carbonate method studied the expansion rates through 3 d,7 d,14 d,28 d,56 d,84 d of the six different ages,and the results showed that the expansion rate of 84 d age of X-6 and Z-5 specimen was more than 0. 1%. By the Test Code for Hydraulic Concrete（SL 352—2006）,andesitic porphyrite has certain potential alkali activity. In summary,the experimental results show that andesitic porphyrite has certain potential alkali activity.