6.6
압축 인자 테스트
압축 계수 시험은 콘크리트의 작업성을 평가하는 데 사용되는 방법입니다. 특히 최대 3.81cm 크기의 골재를 포함하는 콘크리트 혼합물에 적합합니다. 이 시험에는 두 개의 잘린 원뿔 모양 호퍼와 실린더로 구성된 특수 장비가 포함되며, 모두 마찰을 최소화하기 위해 내부 표…
다짐 계수 시험은 최대 1.5인치의 골재 크기를 가진 콘크리트의 작업성을 결정합니다.
테스트 장비는 바닥에 힌지 도어가 있는 두 개의 잘린 원뿔 모양의 호퍼와 실린더로 구성되며, 모두 순차적으로 쌓여 있으며 내부 표면은 마찰을 줄이기 위해 광택이 납니다.
콘크리트를 압축하지 않고 상단 호퍼에 배치하고 하단 도어를 열어 콘크리트가 하단 호퍼로 유입되도록 합니다.
다음으로, 하부 호퍼의 하단 도어를 열어 콘크리트가 아래의 실린더로 떨어지도록 하고 여분의 콘크리트를 쳐냅니다.
강철 막대는 테스트 중에 하나 또는 두 호퍼에 끼인 콘크리트를 부드럽게 찌르고 제거하는 데 사용됩니다.
실린더의 설정 부피에서 콘크리트의 최종 중량이 결정되고 부분적으로 압축된 콘크리트의 밀도가 계산됩니다.
완전히 압축된 밀도는 실린더를 4개의 층으로 콘크리트로 채우고 각 층을 탬핑하여 결정됩니다.
마지막으로, 다짐 계수는 완전히 다진 콘크리트의 밀도에 대한 부분적으로 다진 콘크리트의 밀도의 비율로 계산되며, 이는 혼합물의 작업성을 나타냅니다.
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Q1: What is the compacting factor test used for in concrete testing?
The compacting factor test assesses the workability of concrete, indicating how easily concrete flows and compacts. It measures the ratio of partially compacted concrete density to fully compacted density, providing a numerical value that reflects the concrete's ability to be placed and consolidated in molds during construction projects.
Q2: What equipment is needed to perform a compacting factor test?
The test requires two truncated cone-shaped hoppers with hinged bottom doors, a cylinder for collection, and a steel rod. All equipment has polished interior surfaces to minimize friction and allow concrete to flow freely between components during the test procedure.
Q3: How is the compacting factor value calculated?
The compacting factor is calculated as the ratio of the density of partially compacted concrete to the density of fully compacted concrete. Partially compacted density is obtained from concrete falling through hoppers into a cylinder, while fully compacted density is determined by filling the cylinder in four layers and tamping each layer thoroughly.
Q4: What concrete aggregate sizes are suitable for the compacting factor test?
The compacting factor test is suitable for concrete mixes containing aggregates with a maximum size of one and a half inches. This size limitation ensures the concrete flows properly through the hopper system and provides reliable workability measurements for the specified aggregate range.
Q5: What steps are involved in performing the compacting factor test procedure?
Concrete is placed in the upper hopper without compaction. The bottom door opens, allowing concrete to flow into the lower hopper. The lower hopper door then opens, letting concrete fall into the cylinder below. Excess concrete is struck off, and a steel rod dislodges any stuck material. The cylinder weight is recorded to calculate partially compacted density.
Q6: Why are polished interior surfaces important in compacting factor test equipment?
Polished interior surfaces reduce friction between the concrete and equipment, allowing the concrete to flow freely and naturally through the hoppers and into the cylinder. This minimizes artificial resistance and ensures the test accurately reflects the concrete's true workability characteristics without equipment interference.
Q7: How does the compacting factor test differ from determining fully compacted concrete density?
The compacting factor test measures partially compacted density by allowing concrete to fall freely through hoppers, simulating natural placement conditions. Fully compacted density is determined separately by deliberately filling the cylinder in four layers and tamping each layer to achieve maximum compaction, providing a baseline for comparison.