题名: |
HANDBOOK FOR THE IDENTIFICATION OF ALKALI-SILICA REACTIVITY IN HIGHWAY STRUCTURES, REVISED EDITION. |
关键词: |
Alkali-silica-reactions; Bridges-; Cracking-; Expansion-; Field-tests; Handbooks-; Pavement-distress; Pavements-; Petrography-; Photographs-; Portland-cement-concrete; Reaction-products; Strategic-Highway-Research-Program; Volume-changes |
摘要: |
This handbook provides guidance for the field identification of alkali-silica reactivity (ASR) in portland cement concrete structures such as highway pavements and bridges. ASR development is assessed on two bases: 1) the occurrence and disposition of cracking and displacement of concrete, and 2) the presence of reaction products from ASR. Descriptions and color photographs provide detailed information. The handbook is divided into four sections. Section 1 describes the nature of ASR and its causes and effects. Section 2 deals with the manifestations of ASR-related volume changes in highway pavement. Section 3 covers ASR in bridge structures. Section 4 describes a rapid field procedure to identify the presence of ASR reaction products in concrete. The presence of the reaction products is indisputable evidence of ASR, but it does not necessarily reflect development or severity of distress. Thus, assessment of associated distress together with identification of reaction products provides the greatest assurance whether expansive ASR has developed in the concrete structure. Confirmation of ASR by petrographic analysis is recommended to reach reliable conclusions that the distress is indeed due to ASR expansion. |
总页数: |
2000/05. pp 50 |
报告类型: |
科技报告 |