问题 单项选择题

某电站引水隧洞灰岩段,压力水头50m,岩石饱和单轴抗压强度平均值为108MPa,现场测试的岩体纵波波速为4300m/s,室内测试岩块纵波波速为5100m/s,岩体节理不甚发育,多闭合,平直光滑,沿节理面有线状水流,经节理玫瑰花图判定,主要节理面走向与洞轴线夹角为65°,节理面倾角多在50°左右,延伸长度多小于3m,站址区的地应力以水平应力为主,最大主应力为14MPa,判定其围岩类别并评价其围岩的稳定性()。

A.Ⅰ、稳定

B.Ⅱ、基本稳定

C.Ⅲ、局部稳定性差

D.Ⅳ、不稳定

答案

参考答案:B

解析:饱和单轴抗压强度平均值为108MPa,为坚硬岩,则岩石强度评分A=30;岩体完整性系数K为岩体纵波波速与岩块纵波波速之比的平方,K=0.71,岩体为硬质岩,岩体完整程度为较完整,则岩体完整性评分B=28;岩体结构面不甚发育,多闭合,平直光滑,且为硬质岩,其节理面延伸长度多小于3m,另加3分,则结构面状态评分C=21+3=24:以上各项为基本因素评分,则:T’=30+28+24=82;因压力水头为50m,沿结构面有线状水流,且基本因素评分T’82,则地下水评分D=-2.5:因主要结构面走向与洞轴线夹角为65°,结构面倾角多在50°左右,则结构面产状评分E=-3。T=A+B+C+D+E=76.5围岩强度应力比S=4.5>4,则围岩类别为Ⅱ类,基本稳定。围岩整体稳定,不会产生塑性变形,局部可能产生掉块。

选择题
阅读理解

In most languages, a greeting is usually followed by “small talk”. Small talk means the little things we talk about at start of a conversation. In English-speaking countries people often make small talk about the weather: “Nice day, isn’t it?” But there is something special about small talk. It must be about something which both people have the same opinion about. The purpose of small talk is to let both people agree on something. This makes meeting people easier and more comfortable. People usually agree about the weather, so it is a safer topic for small talk. But people often disagree about religion or politics so these are not suitable topics for small talk in English. The topics for small talk also depend on where the conversation is taking place. At football matches, people make small talk about the game they are watching: “Great game, isn’t it?” At bus stops, people may comment about the transport system: “The bus service is terrible, isn’t it?”

Greetings and small talk are important parts of conversation in any language. The way people greet each other and the things they talk about, however, may be different from one language to another. This shows that there is much more to learn when we learn a language than just the vocabulary and the grammar of the language. We also have to learn the social behavior of the people who speak it.

小题1:Small talk __________ .

A.is a kind of conversation with short words

B.is a greeting when people meet each other

C.is to let people disagree about something

D.is something we talk about to start with a conversation小题2:Why do people need small talk?

A.To choose a topic for conversation.

B.To agree about the weather.

C.To let meeting people become easier and more comfortable.

D.To learn a language.小题3:The passage suggests that when we learn a language ,__________.

A.we should grasp the importance of the language

B.we should know the culture of the language

C.we should only master the grammar and vocabulary

D.we should learn about the transport system of the country