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(1 上海市建筑科學(xué)研究院有限公司, 上海 200032;2 上海市工程結(jié)構(gòu)安全重點(diǎn)實(shí)驗(yàn)室, 上海 200032)

摘要: 為了進(jìn)一步解決對(duì)歷史建筑鋼筋材料強(qiáng)度缺乏了解的問(wèn)題,對(duì)歷史文獻(xiàn)進(jìn)行了調(diào)研,并對(duì)上海某近代混凝土建筑改造工程現(xiàn)場(chǎng)截取的不同規(guī)格型號(hào)的鋼筋進(jìn)行了拉伸試驗(yàn)及里氏硬度試驗(yàn). 結(jié)合歷史文獻(xiàn)調(diào)研結(jié)果及鋼筋制造工藝、拉伸試驗(yàn)及里氏硬度試驗(yàn)結(jié)果,對(duì)近代混凝土建筑中實(shí)測(cè)鋼筋里氏硬度進(jìn)行統(tǒng)計(jì)分析,得到如下結(jié)論:在相當(dāng)于我國(guó)當(dāng)前標(biāo)準(zhǔn)的 HPB235 級(jí)和 HRB335 級(jí)鋼筋之間尚存在屈服強(qiáng)度 275MPa 的鋼筋;當(dāng)采用表面硬度法對(duì)近代混凝土結(jié)構(gòu)中的鋼筋強(qiáng)度等級(jí)進(jìn)行判別時(shí),若實(shí)測(cè)鋼筋里氏硬度代表值大于 400,可判別為 G40 級(jí);若實(shí)測(cè)鋼筋里氏硬度代表值小于 375 時(shí),可判別為 G33 級(jí);在兩者之間時(shí),建議取樣檢測(cè)或偏保守判別為 G33 級(jí);G33級(jí)鋼筋屈服強(qiáng)度可按 HPB235 級(jí)鋼筋取值,G40 級(jí)鋼筋屈服強(qiáng)度可按 275MPa 取值;扭鋼屬于冷扭鋼筋,在進(jìn)行承載力驗(yàn)算時(shí)扭鋼的屈服強(qiáng)度可按 335MPa 取值.

關(guān)鍵詞: 近代鋼筋混凝土結(jié)構(gòu); 鋼筋強(qiáng)度; 里氏硬度; 拉伸試驗(yàn)

中圖分類號(hào):TU375 文獻(xiàn)標(biāo)志碼:A 文章編號(hào):1002-848X(2022)03-0078-07

DOI:10. 19701 / j. jzjg. LS202013

Research on judging method of reinforcement strength in modern reinforced concrete structures

ZHENG Shiju1,2, BAI Xue1,2, JIANG Lixue1,2

(1 Shanghai Research Institute of Building Sciences Co., Ltd., Shanghai 200032, China;2 Shanghai Key Laboratory of Engineering Structure Safety, Shanghai 200032, China)

Abstract: In order to further solve the problem of lack of understanding of the strength of reinforcement in historicalbuildings, the historical documents were investigated, and the tensile test and Leeb hardness test of different specificationsof reinforcement intercepted from a modern concrete building reconstruction project in Shanghai were carried out. Based onthe investigation results of historical documents and the test results of reinforcement manufacturing technology, tensile testand Leeb hardness test, statistical analysis on the measured Leeb hardness of reinforcement in modern concrete buildingswas maked. The following conclusions are drawn: there are still 275MPa reinforcement with yield strength between HPB235grade and HRB335 grade reinforcement in China′s current standards;when the surface hardness method is used to judge thestrength grade of reinforcement in modern concrete structures, if the representative value of reinforcement′s Leeb hardnessis greater than 400, it can be judged as grade G40; if the representative value of reinforcement′s Leeb hardness is less than375, if it can be judged as grade G33; if between the two, it is recommended to take samples for testing or to identify it asG33 conservatively. The yield strength of grade G33 reinforcement can be taken as HPB235 reinforcement, and the yieldstrength of G40 reinforcement can be taken as 275MPa;the torsional steel belongs to cold-torstorsional reinforcement, andthe yield strength of the torsional steel can be calculated according to 335MPa when the bearing capacity is checked.

Keywords:modern reinforced concrete structures; reinforcement strength; Leeb hardness; tensile test

∗上海市科學(xué)技術(shù)委員會(huì)科研項(xiàng)目(19DZ1202400) ,上海市建筑科學(xué)研究院集團(tuán)科研創(chuàng)新課題(KY10000038. 20190003) .

第一作者:鄭士舉,碩士,高級(jí)工程師,主要從事既有建筑檢測(cè)評(píng)估與加固改造,Email:zsj85408048@ 163. com.

[引用本文] 鄭士舉,白雪,蔣利學(xué). 近代鋼筋混凝土結(jié)構(gòu)的鋼筋強(qiáng)度判別方法研究[ J] . 建筑結(jié)構(gòu),2022,52( 3) :78-84. ZHENG Shiju,BAI Xue,JIANG Lixue. Research on judging method of reinforcement strength in modern reinforcedconcrete structures[ J] . Building Structure,2022,52(3) :78-84.