JPKIC 构盘计原 Example:a span of 4m,a concentrated load at midspan of tested beam,beam section size is 200 X300mm,concrete is C20. Please see: 200 4000 A A一A 200 210 4000 B 316 b) B—B
Example: a span of 4m, a concentrated load at midspan of tested beam, beam section size is 200 ×300mm, concrete is C20. Please see: 4000 A A F a) 200 300 A－A b) 4000 B B B－B 200 300 210 316
JIPKIC 结构热计原黑 Testing results: In fig.a),for plain concrete beam,the ultimate load P=8kN, controlled by the concrete tensile strength,failure modes: brittle failure In fig.b),the ultimate load of RC beam P=36kN,the steel rebar is in tension,and concrete is in compression to crush, failure mode:ductile failure (appropriate steel reinforcement) This can be concluded:the effectiveness of combination of steel and concrete: 1,greatly enhance the load-carrying capacity 2,improve the mechanical performance of structure
Testing results: • In fig. a),for plain concrete beam, the ultimate load P = 8kN, controlled by the concrete tensile strength, failure modes: brittle failure • In fig. b) , the ultimate load of RC beam P = 36kN, the steel rebar is in tension, and concrete is in compression to crush, failure mode: ductile failure (appropriate steel reinforcement) • This can be concluded: the effectiveness of combination of steel and concrete: 1, greatly enhance the load-carrying capacity 2, improve the mechanical performance of structure
JPKIC 结构计原黑 2.Reasons for steel and concrete working together (1)a good bond strength between them (2)The temperature linear expansion coefficient are close steel a=1.2×10-5 concrete ac=1.0 ~1.5 x 10-5 (3)Steel rebar embedded in concrete,which can prevent steel from rust
2、Reasons for steel and concrete working together (1) a good bond strength between them (2) The temperature linear expansion coefficient are close (3) Steel rebar embedded in concrete, which can prevent steel from rust. steel st = 1.2 10–5 concrete ct = 1.0 ～ 1.5 10–5
JPKIC 结构设计原理 The principle of structure design 3.The main advantages and disadvantages of RC structures ·Advantages: 1)rich materials resource,saving steel 2)Durability 3)good fire resistance 4)mold well,easy realization of structural type; 5)A good structural integrity due to cast-in-site
3、 The main advantages and disadvantages of RC structures • Advantages： 1) rich materials resource, saving steel 2) Durability 3) good fire resistance 4) mold well, easy realization of structural type; 5) A good structural integrity due to cast-in-site
JPKIC Disadvantages: 结构势计原黑 (1 high self-weight solution Light aggregate material (2)Crack resistance is,work with cracks solution Prestressed concrete (3)Construction is impacted by climate conditions,the a long construction period (4)More mold tools and wood waste (5 )Difficult strengthening and reconstruction,poor heat and noise-resistance performance
⚫ Disadvantages： （2）Crack resistance is, work with cracks （3）Construction is impacted by climate conditions, the a long construction period (4 ) More mold tools and wood waste （5）Difficult strengthening and reconstruction, poor heat and noise- resistance performance. （1）high self-weight Light aggregate material Prestressed concrete solution solution