四川交通职业技术学院-土木工程英语

1、四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &Technical College of Communications 土木工程英语土木工程英语四川交通职业技术学院教学课件四川交通职业技术学院教学课件(The 2nd Talent-Competition for Teachers of SVTCC)l国家示范性高等职业技术学院国家示范性高等职业技术学院教师：黄教师：黄 蜀蜀 云云n公共课教学部Unit 6Stress & Deformation English for Civil EngineeringRoad Engineering四

2、川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nLead-incopyright黄蜀云 Stress is the physical pressure or other forces exerted on an object.Deformation in any directi

3、on is the total change in the dimension of a member in that direction.Deformation Force English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Gui

4、ded Writing(写作写作)|nLead-incopyright黄蜀云 pre-stressing operatingWork platformAnchor boltsrebarconcrete English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercis

5、es(练习练习) |Guided Writing(写作写作)|nDialoguecopyright黄蜀云 A: Since many pre-stressing reinforced concrete components are adopted in project , it is necessary to have a look at the pre-stressing operating .fixing formworkexerting tension English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sic

6、huan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nDialoguecopyright黄蜀云 B: The rebar is pre-stressed first by a certain tension force and fixed on both ends. Then we fix the formwork and n

7、on-prestressed rebar, and then pour concrete. After the concrete reaches the designed strength , the pre-stressed rebar are released .pouring concretereleasing rebar English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国

8、家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nDialoguecopyright黄蜀云 B: The rebar is pre-stressed first by a certain tension force and fixed on both ends. Then we fix the formwork and non-prestressed rebar, and then pour concrete. After the concrete r

9、eaches the designed strength , the pre-stressed rebar are released .releasing rebarpouring concrete English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercise

10、s(练习练习) |Guided Writing(写作写作)|nDialoguecopyright黄蜀云 A: The strength from the pre- stressing members is transferred to the concrete , isnt it ?B: Yes. The pre-stressed concrete will offset some or all the tension force when it is under the situation of tension strength.rebaroffset the tension force P

11、ressure English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nDialoguecopyright黄蜀云 A: Are there any differences between the

12、 pre-stressed concrete and non-prestressed concrete in concrete pouring?B: In order to reduce the concrete shrinkage under the pre-stressing , the pre-stressed concrete should be poured continuously in one time without construction joints . the ratio of water and cement should be low and the aggrega

13、te should be selected in better quality .construction joints English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nDialogue

14、copyright黄蜀云 A: When can the fixtures of the prestressed rebar be removed ?B: It depends on whether the concrete strength reaches the designed value or not. At least the test should show that the result is up to the standard. if the fixture are released too early , it will cause lots of strength los

15、s and even serious quality problem . English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nDialoguecopyright黄蜀云 Technical T

16、erms of the Dialogue1.模板2.水泥3.骨料4.钢筋混凝土5.预应力6.预应力钢筋 7.施工缝8.拉(张)力 English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nDial

17、oguecopyright黄蜀云 Try to explain in your own words the technical terms learned in the dialogue and then talk about the process of pre-stressing operation. English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院

18、|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 When designing a structure ,the designer must estimate all the forces acting on the structure and its component parts . The effects of the forces are then considered in relation to the stability of

19、a building as a whole and component parts are made strong enough to carry their particular function . English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exerci

20、ses(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 The forces to be considered depend on the type and purpose of the structure . In buildings ,for example ,the forces will be due to the weight of the structure and its occupants as well as to the pressure exerted by wind . English for Civil Engineerin

21、gRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 The loads of a building English for Civil EngineeringRoad Engineering四川交通职业技术学院四

22、川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 In the wall for retaining earth ,the forces will be due to the weight of the wall, the pressure exerted on t

23、he wall by the earth behind it ,and the pressure due to any buildings or roadways near the top of the wall .挡土墙受力 English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文

24、课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 The internal fibers or particles of the various parts of a structure are put into a state of stress by the forces they are needed to resist ,the basic forms of stress being tension , compression ,shear and torsion .batensioncompression En

25、glish for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 In tension ,the material is pulled apart or stretched

26、like a rubber band . In compression ,the material is pressed or pushed together . English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Wr

27、iting(写作写作)|nTextcopyright黄蜀云 What is torsion ?It makes the structure rotate or turn .torsion English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习

28、) |Guided Writing(写作写作)|nTextcopyright黄蜀云 The shearing force causes shearing stress . It is defined as the fracture of the materials along the stress route .shearFF English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家

29、示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 Since the structure designed by civil engineers is intended to be stable ,these forces must be kept in balance . The vertical forces ,for example ,must be equal to each other . if a beam

30、supports a load above ,the beam itself must have sufficient strength to counterbalance that weight .F1F2F1F2= English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文)

31、| Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 The horizontal forces must also be equal to each other so that there is not too much thrust either to the right or to the left .the forces that might pull the structure around must be counterbalanced with forces that pull in the opposite dire

32、ction .F1F2=F2F1 English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 if a man carries a heavy load ,his

33、body is distressed as a result of the efforts he has to make to bear the load . In order to grasp the idea of stress, it is helpful to compare fibers of a material subjected to force to the bones and muscles of a man . English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocation

34、al &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 A material is sure to deform to a greater or lesser extent when it is subjected to stress ,although the dimensional variations in str

35、uctural materials are usually very slight .the deformation produced is often called strain .a member stressed in compression becomes shorter and fatter . English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院

36、|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writing(写作写作)|nTextcopyright黄蜀云 Questions1. What should a designer estimate in designing a structure2. What are the four basic forms of stress?3. How can the forces of the structure be kept in balance?4. In what condition does a material deform? Take an example English for Civil EngineeringRoad Engineering四川交通职业技术学院四川交通职业技术学院Sichuan Vocational &TechnicalCollege of Communicationsn国家示范性高等职业技术学院国家示范性高等职业技术学院|Lead-in(导入导入)| Dialogue(对话对话) |Text (课文课文) | Exercises(练习练习) |Guided Writi