- 摘 要
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（中國建筑科學(xué)研究院建筑結(jié)構(gòu)研究所， 北京 100013）
［摘要］超長混凝土結(jié)構(gòu)產(chǎn)生拉應(yīng)力的因素相對較多，使控制部位組合拉應(yīng)力隨之增大，不易按常規(guī)控制其出現(xiàn)寬度超限裂縫，目前設(shè)計與施工基本僅憑經(jīng)驗選用溫度后澆帶、膨脹加強(qiáng)帶、混凝土膨脹劑等為主要抗裂措施。結(jié)合現(xiàn)有研究成果，從多角度對此進(jìn)行了深入分析研究，得到以下結(jié)論：超長混凝土結(jié)構(gòu)的抗裂驗算應(yīng)合理組合非重力荷載效應(yīng)；各項抗裂措施的預(yù)期綜合效果應(yīng)經(jīng)驗算確認(rèn)可行；抗裂控制標(biāo)準(zhǔn)宜基于《混凝土結(jié)構(gòu)設(shè)計規(guī)范》（GB 50010—2010）相應(yīng)下限值分不同部位適當(dāng)提高，且不應(yīng)因結(jié)構(gòu)設(shè)有外防水層而降低。此外，研究還提出了相關(guān)技術(shù)建議與補充措施。
［關(guān)鍵詞］超長混凝土結(jié)構(gòu)； 最大裂縫寬度； 耐久性； 溫度后澆帶； 彈塑性分析； 組合拉應(yīng)力
中圖分類號：TU375文獻(xiàn)標(biāo)識碼：A文章編號：1002-848X(2017)24-0068-04
Study on cracking control in design of super-long reinforced concrete structures
Pan Li
(Institute of Building Structures, China Academy of Building Research, Beijing 100013, China)
Abstract:There are many factors contributing to tensile stress in super-long reinforced concrete structures, followed by increasing of combined tensile stress in the control parts, and it is not easy to prevent out-of-code cracks according to common measures. The main cracking control measures in current design and construction are basically based on experience, and include temperature late-poured band, expansion-reinforcing band and expansion concrete. Combined with existing research results, further researches were conducted on above issues. Conclusions are that: the effect of non-gravitational loads should be combined reasonably while the maximum crack width is checked for super-long reinforced concrete structures; the integrated expected effect of anti-crack measures should be confirmed by calculation; the anti-crack criterion based on lower limit in Code for design of concrete structures（GB 50010—2010）should be increased appropriately with different degrees in different structural parts, and it should not be lowered due to outer water-resisting structural layer. Furthermore, some useful technical suggestions and supplementary measures were proposed.
Keywords:super-long reinforced concrete structure; maximum crack width; durability; temperature late-poured band; elastic-plastic analysis; combined tensile stress
作者簡介：潘立，碩士，教授級高級工程師，一級注冊結(jié)構(gòu)工程師，Email: panlicabr@163.com。
