基于小尺寸非标准试件的混凝土强度评定

关键字：混凝土,非标准试件,抗折强度,抗压强度,回归分析

（浙江建设职业技术学院 建工系，浙江 杭州  311231）
 

    摘要：目前，绝大多数相关混凝土技术标准和规范均以标准试件测试抗折强度，这类试件往往尺寸[150 mm×150 mm×600 mm（或525、550） mm]和质量（28～33 kg）较大，给试验操作带来了诸多困难甚至安全隐患。试验性地探索了以小尺寸非标准试件（100 mm×100 mm×300 mm棱柱体）评定抗折强度的可行性，并尝试以这种试件折断后的部分经切割得到的边长100 mm的立方体试件评定抗压强度。此外，还对比分析了小尺寸非标准试件和标准试件的强度评定结果，并考察了它们的相关性。以12种包括不同原材料和配合比的典型交通工程结构混凝土作为考察对象。结果表明，所采用的非标准小尺寸试件能用于评定混凝土抗折强度和抗压强度，由回归分析得到的2种强度的相关性公式适用于文献中的实测数据。
    关键词：混凝土；非标准试件；抗折强度；抗压强度；回归分析；相关性；强度预测
    中图文分类号：TU528        文献标识码：A        文章编号：1001-702X（2017）06-0023-05

Study on concrete strength assessment based on non-standard small size specimens
PAN Lijun，CHEN Weidong，JIANG Chenhui
（Department of Architectural Engineering，Zhejiang College of Construction，Hangzhou 311231，China）

    Abstract：At present，in many standards and technical specifications，the flexural strength is often measured using standard specimens with sizes[e g.，150×150×600（550~525） mm prisms] and weights（28~33 kg） which incur a lot of operational difficulties. This paper presents an experimental study that conducts flexural strength tests using non-standard small size specimens（i e.，100 mm×100 mm×300 mm prisms）and the use of specimen ends（i.e.，100 mm cubes sawn from the broken parts of 100 mm×100 mm×300 mm prisms after flexural tests） for compressive strength tests. Additionally，strength assessment result is obtained from the non-standard specimens and standard specimens，and the relativity between them was also investigated. The experiments are performed on 12 mixtures with various ingredients and proportions. The study concludes that non-standard small size specimens can be used as an alternative for evaluating flexural and compressive strengths of modern concrete. The proposed relativity equation obtained by regression analysis of the two strengths matches well with actual data in literature.
    Key words：concrete，non-standard specimen，flexural strength，compressive strength，regression analysis，relativity，strength prediction