问题 单项选择题

下列()不是影响回弹法检测混凝土强度的因素。

A.测试角度

B.浇筑面

C.碳化深度

D.骨料粒径

答案

参考答案:D

解析:回弹法检测混凝土抗压强度原理是根据混凝土硬化后其表面硬度(主要是混凝土内部砂浆的硬度)与抗压强度之间有一定相关关系,通过正确建立抗压强度f与回弹值R之间的关系曲线(或公式),来测试混凝土抗压强度。为提高测试精度应弄清回弹法测试混凝土强度的影响因素,主要有:原材料、外加剂、成型方法、养护方法及湿度、碳化及龄期、模板、泵送混凝土、测试角度及其他,依据影响的程度和相互关系,回弹法硷测混凝土抗压强度技术规程对影响程度较大的进行修正,有浇注面、测试角度、碳化深度、泵送等。

单项选择题

(一)


Right is right. Right Of course. But is left wrong Well, the Romans used to think so. They thought left-handed people were mistakes of nature. Latin, the language of the Romans, had many Words that expressed this view. Some words we use today still have this meaning. The Latin word "dexter" means "right". The English word "dexterous" comes from this word. It means "handy" ( clever with hands). So, right is handy. But the Latin word for left is "sinister". The English word "sinister" comes from this word. Sinister means "evil" (very bad). Is it fair to call right-handed people handy and: left-handed people evil Well, fair or not, many languages have words that express such beliefs. In old English, the word for left means "weak". That isn’t much of an improvement over "evil".
Not very long ago, children were often forced to write with their right hands. Doctors have since found that this can be very harmful. You should use the hand you were born to use.
People who use their left hands are just starting to get better treatment. But why they get all these bad names in the first place One reason may be that there are not as many left-handed people as there are right-handed people. There is one left-handed person for every five right- handed ones. People who are different are often thought to be wrong. But attitudes do seem to be changing. Fair-minded right-handed people are finally starting to give left-handed people a hand.

What does the passage lead us to believe when one writes

A.He can only use his right hand.

B.He can only use his left hand.

C.He can use either his left hand or his right hand.

D.He can use both his left hand and his right han

单项选择题