英语翻译1.4.3 \x05Age of Test Specimen Kolek10 has indicated that the rate of gain of surface hardness of concrete is rapid up to the age of 7 days,following which there is little or no gain in the surface hardness; however,for a properly cured c

英语翻译1.4.3 \x05Age of Test Specimen Kolek10 has indicated that the rate of gain of surface hardness of concrete is rapid up to the age of 7 days,following which there is little or no gain in the surface hardness; however,for a properly cured c
英语翻译
1.4.3 \x05Age of Test Specimen
Kolek10 has indicated that the rate of gain of surface hardness of concrete is rapid up to the age of 7 days,following which there is little or no gain in the surface hardness; however,for a properly cured concrete,there is significant strength gain beyond 7 days.It has been confirmed by Zoldners14 and Victor16 that for equal strength,higher rebound values are obtained on 7-day-old concrete than on 28-day-old concrete.It is emphasized that when old concrete is to be tested,direct correlations are necessary between the rebound numbers taken on the structure and the compressive strength of cores taken from the structure.
\x05The use of the Schmidt hammer for testing low-strength concrete at early ages,or where concrete strength is less than 7 MPa,is not recommended because rebound numbers are too low for accurate reading and the test hammer badly damages the concrete surface.14 Figure 1.10 shows blemishes caused by rebound tests on surfaces of 8-h-old and 3-day-old concrete cylinders.
FIGURE 1.10 Eight-hour-old (left) and the three-day-old (right) specimens showing surface blemishes after Schmidt hammer impact.(Adapted from Reference 14.)
Surface Hardness Methods\x051-9
1.4.4\x05Surface and Internal Moisture Condition of the Concrete
The degree of saturation of the concrete and the presence of surface moisture have a decisive effect on the evaluation of test hammer results.11,16,17 Zoldners13 has demonstrated that well-cured,air-dried specimens,when soaked in water and tested in the saturated surface-dried condition,show rebound readings 5 points lower than when tested dry.When the same specimens were left in a room at 70˚F (21.1˚C) and air dried,they recovered 3 points in 3 days and 5 points in 7 days.Klieger et al.18 have shown that for a 3-year-old concrete differences up to 10 to 12 points in rebound numbers existed between specimens stored in a wet condition and laboratory-dry samples.This difference in rebound numbers represents approximately 14 MPa difference in compressive strength.
\x05It is suggested that,whenever the actual condition of the field concrete or specimens is not known,it would be desirable to presaturate the surface several hours prior to testing and use the correlation for tests on saturated surface-dried specimens.

英语翻译1.4.3 \x05Age of Test Specimen Kolek10 has indicated that the rate of gain of surface hardness of concrete is rapid up to the age of 7 days,following which there is little or no gain in the surface hardness; however,for a properly cured c
1.4.3测试样本的时代
　　Kolek10率表明,获得的表面硬度混凝土快速岁以前的7天,接下来很少或根本没有获得在其表面硬度;然而,适当的混凝土治愈,有明显的力量获得超过7天.已经证实,由Zoldners14和Victor16平等强度、高回弹值超过了混凝土7-day-old 28-day-old混凝土.强调当老混凝土是测试施密特锤的使用测试摘要素混凝土早期年龄,或在混凝土强度不足7 MPa、并不可取,因为反弹编号太低了准确阅读和测试混凝土表面的严重损害锤.14图1.10显示磨损造成的表面反弹测试8-h-old和3-day-old混凝土气罐.

只有这么点分。。。谁那么闲

Kolek10率表明,获得的表面硬度混凝土快速岁以前的7天,接下来很少或根本没有获得在其表面硬度;然而,适当的混凝土治愈,有明显的力量获得超过7天。已经证实,由Zoldners14和Victor16平等强度、高回弹值超过了混凝土7-day-old 28-day-old混凝土。强调当旧混凝土是测试,是必要的直接相关性之间反弹了结构和数量的抗压强度取芯结构。
施密特锤的使用测试摘要素混凝土早期...

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Kolek10率表明,获得的表面硬度混凝土快速岁以前的7天,接下来很少或根本没有获得在其表面硬度;然而,适当的混凝土治愈,有明显的力量获得超过7天。已经证实,由Zoldners14和Victor16平等强度、高回弹值超过了混凝土7-day-old 28-day-old混凝土。强调当旧混凝土是测试,是必要的直接相关性之间反弹了结构和数量的抗压强度取芯结构。
施密特锤的使用测试摘要素混凝土早期年龄,或在混凝土强度不足7 MPa、并不可取,因为反弹编号太低了准确阅读和测试混凝土表面的严重损害锤。14图1.10显示磨损造成的表面反弹测试8-h-old和3-day-old混凝土气罐。
图1.10 Eight-hour-old(左)和(右)标本显示去年表面磨损后锤冲击施密特。(改编自参考14。)
表面硬度的方法- 9
1.4.4表面和内部水分条件下的混凝土
的程度,饱和混凝土的水分和在场的表面有一个决定性的影响锤评价试验结果。十一、16、17 Zoldners13表明well-cured,标本风干,当浸泡在水里的饱和surface-dried与测试条件,表明反弹读数低于5分的测试时,干燥。当同一标本都留在一个房间70˚F(21.1˚C)和空气干燥,恢复3点三天,5点7天。徐慰凯等。al.18表明对于一个三岁的具体差异到10到12点反弹编号之间存在着标本保存在一个潮湿的情况下,laboratory-dry样品。这种差异在反弹编号代表大约14帕在抗压强度差异。
建议时,现场的实际情况具体或标本是不为人所知,宜几小时前presaturate表面测试和使用相关测试对饱和surface-dried标本。

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