ASTM C900-15
硬化混凝土拔出强度的标准测试方法
Standard Test Method for Pullout Strength of Hardened Concrete
- 标准号
- ASTM C900-15
- 发布
- 2015年
- 发布单位
- 美国材料与试验协会
- 替代标准
- ASTM C900-19
- 当前最新
- ASTM C900-19
- 引用标准
- ASTM C125 ASTM C670 ASTM E4 ASTM E74
- 适用范围
5.1 For a given concrete and a given test apparatus, pullout strengths can be related to compressive strength test results. Such strength relationships are affected by the configuration of the embedded insert, bearing ring dimensions, depth of embedment, and the type of aggregate (lightweight or normal weight). Before use, the relationships must be established for each test system and each new concrete mixture. Such relationships are more reliable if both pullout test specimens and compressive strength test specimens are of similar size, consolidated to similar density, and cured under similar conditions.
Note 1: Published reports (1-17)4 by different researchers present their experiences in the use of pullout test equipment. Refer to ACI 228.1R (14) for guidance on establishing a strength relationship and interpreting test results. The Appendix provides a means for comparing pullout strengths obtained using different configurations.
5.2 If a strength relationship has been established experimentally and accepted by the specifier of tests, pullout tests are used to estimate the in-place strength of concrete to establish whether it has reached a specified level so that, for example:
(1) post-tensioning may proceed;
(2) forms and shores may be removed;
(3) structure may be placed into service; or
(4) winter protection and curing may be terminated.
In addition, post-installed pullout tests may be used to estimate the strength of concrete in existing construction.
5.3 When planning pullout tests and analyzing test results, consideration should be given to the normally expected decrease of concrete strength with increasing height within a given concrete placement in a structural element.
5.4 The measured pullout strength is indicative of the strength of concrete within the region represented by the conic frustum defined by the insert head and bearing ring. For typical surface installations, pullout strengths are indicative of the quality of the outer zone of concrete members and can be of benefit in evaluating the cover zone of reinforced concrete members.
5.5 Cast-in-place inserts require that their locations in the structure be planned in advance of concrete placement. Post-installed inserts can be placed at any desired location in the structure provided the requirements of
● 拔出法无损检测拔出法是将安装在混凝土中的锚固件拔出，测出最大拔出力，根据预先建立的拔出力与混凝土强度之间的关系推进混凝土强度的方法。这是一种局部微破损检测方法。拔出法分为两类，一类是预埋拔出法，即在混凝土构件或构件的施工过程中预先安装锚固件，待混凝土硬化再将锚件拔出，检验新浇混凝土的强度。...