我們都知道,任何事物在承受到一定壓力之后,都會(huì)發(fā)生一些量變或者質(zhì)變,對(duì)于鋼筋來(lái)說(shuō)也是如此。普通鋼筋由于本身的局限性,不能很好得承受更大的壓力,因此便有了抗震鋼筋的存在,今天就簡(jiǎn)單給大家講一下抗震鋼筋要求都有哪些。
As we all know, after enduring certain pressure, everything will undergo some quantitative or qualitative changes, the same is true for reinforcing bars. Because of its own limitations, ordinary steel bars can not well withstand greater pressure, so there is the existence of anti-seismic steel bars. Today, I will simply tell you what the requirements of anti-seismic steel bars are.
抗震鋼筋要求之概念:質(zhì)檢總局和標(biāo)準(zhǔn)化委員會(huì)共同發(fā)布的GB1499.2–2007《鋼筋混凝土用鋼第2部份:熱軋帶肋鋼筋》。標(biāo)準(zhǔn)中明確規(guī)定,抗震鋼筋的符號(hào)為在較高要求的抗震結(jié)構(gòu)牌號(hào)后加“E”,例如HRB400E,HRB500E。“E”,是英語(yǔ)單詞Earthquake(地震)的個(gè)字母,標(biāo)志著鋼筋產(chǎn)品達(dá)到了頒布的“抗震”標(biāo)準(zhǔn)。
Concepts of Requirements for Seismic Reinforcement: GB1499.2-2007 "Steel for Reinforced Concrete Part 2: Hot Rolled Ribbed Reinforcement Bars" issued jointly by the General Administration of Quality Supervision and Inspection and the National Standardization Committee. It is clearly stipulated in the standard that the symbol of aseismic reinforcement is "E" after the higher demanding aseismic structural grade, such as HRB400E and HRB500E. "E" is the first letter of the English word Earthquake, which indicates that the steel products have reached the "seismic" standard promulgated by the state.
抗震鋼筋要求除應(yīng)滿足標(biāo)準(zhǔn)所規(guī)定普通鋼筋所有性能指標(biāo)外,還應(yīng)滿足以下:
In addition to meeting all the performance indexes of ordinary steel bars specified in the standard, the requirements of aseismic steel bars should also meet the following requirements:
1.抗震鋼筋的實(shí)測(cè)抗拉強(qiáng)度與實(shí)測(cè)屈服強(qiáng)度特征值之比不小于1.25;
1. The ratio of the measured tensile strength to the measured yield strength is not less than 1.25.
2.鋼筋的實(shí)測(cè)屈服強(qiáng)度與標(biāo)準(zhǔn)規(guī)定的屈服強(qiáng)度特征值之比不大于1.30;
2. The ratio of the measured yield strength to the characteristic value of the yield strength specified in the standard is not more than 1.30.
3.鋼筋的大力總伸長(zhǎng)不小于9%。
3. The maximum total elongation of steel bar is not less than 9%.
以上三條確保了鋼筋的抗震能力,使得抗震鋼筋能夠在建筑發(fā)生傾斜、變形時(shí)“穩(wěn)起”,不發(fā)生斷裂。
The above three elements ensure the anti-seismic ability of the steel bars, so that the anti-seismic steel bars can be "stabilized" when the buildings are inclined and deformed, and do not break.
不過(guò)從新標(biāo)準(zhǔn)對(duì)抗震鋼筋的三條規(guī)定要求來(lái)看,主要針對(duì)鋼筋強(qiáng)度和伸長(zhǎng)率的實(shí)測(cè)值在技術(shù)指標(biāo)上作了一定的提升,如條對(duì)抗震鋼筋規(guī)定從屈服到拉斷還應(yīng)承受25%以上的拉力;第二條保證鋼筋屈服強(qiáng)度離散性不會(huì)過(guò)大而影響到設(shè)計(jì)對(duì)結(jié)構(gòu)延性要求的效果;第三條由對(duì)普通鋼筋規(guī)定的大力總伸長(zhǎng)率不小于7.5%提高到不小于9%。這些技術(shù)指標(biāo)的提高,加強(qiáng)了鋼筋的抗震能力,保證了結(jié)構(gòu)構(gòu)件在地震力作用下具有更好的延性。
However, according to the three requirements of the new standard for seismic steel bars, the measured values of strength and elongation of steel bars have been improved to some extent in technical indicators, such as the first stipulation that seismic steel bars should bear more than 25% tension from yielding to breaking; the second one guarantees that the discreteness of yield strength of steel bars will not be too large to affect the effect of ductility requirement in design; and the third one guarantees that the discreteness of yield strength of steel bars will not be too large 條由對(duì)普通鋼筋規(guī)定的大力總伸長(zhǎng)率不小于7.5%提高到不小于9%。 The improvement of these technical indicators strengthens the seismic capacity of steel bars and ensures that structural members have better ductility under seismic force.
因此,抗震鋼筋和普通鋼筋的本質(zhì)區(qū)別就是使鋼筋獲得更好的延性,從而能夠更好地保證重要結(jié)構(gòu)構(gòu)件在地震時(shí)具有足夠的塑性變形能力和耗能能力。
Therefore, the essential difference between aseismic steel bar and ordinary steel bar is to make the steel bar have better ductility, which can better ensure that the important structural components have sufficient plastic deformation capacity and energy dissipation capacity in earthquake.