碱骨料比长仪操作规程

碱骨料比长仪操作规程
英文回答：
Alkali-Aggregate Reactivity Length Test Procedure.
Purpose:
To determine the potential for alkali-aggregate reactivity (AAR) in concrete by measuring the expansion of concrete specimens subjected to an accelerated weathering cycle.
Equipment:
Mortar bars (1" x 1" x 11.25")。

2.25% NaOH solution.
Accelerated weathering chamber.
Procedure:
1. Cast mortar bars with the specified cement and aggregate proportions.
2. Cure the bars in a moist environment for 24 hours.
3. Remove the bars from the curing chamber and store them in the accelerated weathering chamber.
4. Expose the bars to a cycle of alternating wetting and drying for a period of 14 days.
5. Measure the change in length of the bars after each cycle.
6. Calculate the average expansion of the bars over the 14-day period.
Interpretation:
The expansion of the mortar bars is used to assess the
potential for AAR. The following criteria are generally used:
Expansion < 0.020%: No significant risk of AAR.
Expansion 0.020% 0.050%: Low risk of AAR.
Expansion > 0.050%: High risk of AAR.
中文回答：
碱骨料比长仪操作规程。

目的：
通过测量混凝土试件在加速风化循环作用下的膨胀量，来确定混凝土中碱骨料反应 (AAR) 的可能性。

设备：
砂浆条（1" x 1" x 11.25"）。

2.25% NaOH溶液。

加速风化箱。

程序：
1. 用指定的胶结材料和骨料配比浇铸砂浆条。

2. 将条子在潮湿环境中养护24小时。

3. 从养护室中取出条子，并将其置于加速风化箱中。

4. 将条子暴露于14天的交替湿润和干燥循环中。

5. 在每个循环后测量条子的长度变化。

6. 计算条子在14天期间的平均膨胀量。

解释：
砂浆条的膨胀量用于评估AAR的可能性。

一般使用以下标准：
膨胀<0.020%，无显着的AAR风险。

膨胀0.020% 0.050%，AAR风险低。

膨胀>0.050%，AAR风险高。