一简支梁如图3所示,混凝土为C30,荷载设计值为两个集中力F=100kN,忽略梁自重的影响,环境类别为一类,纵向受拉钢筋采用HRB400级钢筋,箍筋采用HRB335级钢筋,试求:(1)所需纵向受拉钢筋:(2)求受剪箍筋(无弯起钢筋)(3)利用受拉纵筋为弯起钢筋时,求所需箍筋。

题目解答
答案
答:做梁的内力图如下: 17d1412e368c04e.png 已知,IS6bhiwMppHaCmQ3txU57BonareS0d0llfvIX0RZfz228ZejUa4CMauUS2e5FGpsNqfDFE9gdCEKrAjDRuerlzHuQFgiBB8Q4kKAxHx9pvQtuzIQz43cE8ETXjdWbWu5rHuMRHfinWruo4PJKSTK0tfpgF/f8DQrxgK5bT4xG3E+QhiLi9vqbWFrRF/nc/QmrOQIP+Fm0iOY0VHauy1fqB/hj5bSc+NoSASzLF7jX24UGXn3Fx6qUyCrNHfSnc1V (1)弯矩设计值为WEV8Y0ldXDhVIy1TRL0Leg== 设ai4N21ltmDTvi08LNfK0h1wO8kULynvFrXqWNUtBSQGTZKX4D0wEQ2UT4i1sRdQA11r9U7URqVls68GOkB0OHLlXT2d+LUQVjO9pthSLHYM= 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 选用NVfBsBJ3yAAQdVknWGUukzp3SQ6pIzEMb7k3ES7ygBDME5uF2MO8RJZaqk2OEWvO Ob+xA3k4gMEop8ux/Z7+LpPaXoHQstDCqwqIIyeyCVJgD63pkved6stpRRlONRI25cypqZ5qMWjHwyRe1HYmZP6HKgTVjbZtgCiGNczhFWAujRhgcBOmKkKVBb35LMnifVuZlGGTl/tGPPsK/Fdx6xiY8fKBLSBLzapIL9AKQt9dNPMqqS1SHnrHNamijRZH 同时,Eu+SDQZ2K7bq93xdqB6dHQ==,满足要求 (2)无弯起钢筋,进行配计算 剪力设计值为WxzlqCSw8C90Unx2nkylig== ①验算截面尺寸: NJBJ/4wydeYL3j3dRRhnl6vWErDRU2p7sm89STELr6A0a2Phm/y7+cel4A/WtuiY, Inf3u2EG1hemXqJyDCged6a/IDeW8T3qwlZJdv2QvSY5wz29qoCD2w+NT3WzaQ/P,属于厚腹梁。混凝土强度为iGh3LBsLmWZI+fQNsK2a3Q==,取egiT0lap5iKXH+8PSmPb0A== Ju1g9gIUvef/aNKpDKQ3aTQL9z8E9FbhlJI14B+k/o2pWdB7pvLnkTMIBQx+86FZNCXS/yTL1BKKZmpOd5SzgAyaR15ZViifIIbB2maSPJjNiQVLNIBIPZqsRBLNiGxIPJt1a+VXRdlmHabBiETjKw==符合截面要求 ②验算是否需要按计算配置箍筋,简支梁承受集中荷载: Uhu2/1bhRl3dw2iQmc0iyResQDhf3lpnyFy/QtoAG1ZTRK/f4fa60JYtVd+xdQpBMh1mIzFqcD5aKDQZZDUTwZFTROTFtejTdT16BVTYEJlZgf8yZn8cElemCitX2DHER+TO/4Pqx/YSZIRGXhErhn3IEoH7Lbt/Iefy9XkQO43ID7MApGEvrnRzuS2vtqg/9ztvQlxUCOpwdY1SUCCJbJI/r9NIC6Jb4Pd6vzPKrePrJN7iQlkfPOXPLBlN/bNT 故需要通过计算配置箍筋。 ③计算箍筋: 由+GWzFb7+kBe/VMcGBOPBgVwZS9r7eqdohIGLYdGc7TxsCaMuZgwVVzf2+yGbT66T+XSRJevtFQRWS2SHXhcGeYI/6tuO73Iwm9992e40Q7V9Mfe/mBi7w4n9ybQNFw1u可得, 8ZjKnAWyV2bjMRqsb4ItR482Hckdkt2l3ZNph+iwCVrQv1Yrbs+gaAf5XO4P3StzHI4t2YlCU7Qg7I9CuYGWwyCoB9EHgPeYvYWhEb0qL73C/x2mdv0ciNAwhEL16RTSqrWF2rBTm/SOiM/YsmW1XYo1rZmTVDKKMjE1xS8sE8HzrSdj2BJhHGFgXYvRWrqV4AWfCroZM81lzTTaNkfwsQ== 采用双肢箍筋中C9s1ZyoY/QXTyUV8lDWETE8SAdmlK0Em0HSAydw8pPqeBH52e9c2Vk5O6Z0S2BiBrFBZjNfeyDbuhNDmy7cX7g==, Hl7TDtIJ9wTC76avMQ+5tLsvqwkV5dkUIUuiC7VG7CmSVayqmY3MddTRR4OWL1oDRsulRNxUqy29XKxTOmaqUQr8ui1Fd8MqfsLIEYHvwQjGFJ53B9tvk7N6izlBTv2rq88YROEFoWviQpdHBoxU9a0wNiUzfhQmfG3bO9cugn8=符合要求。 验算ubhFWHRUCkZDuJc6Rt+hiy5aumbocfwV91/bj7VqcpQR+CrhHO+wokYE+SkO85iXklXprHZ682yyMZ4b4JNTGHA/XegPH9kWt9uRmjwSOgiMrSbsTsHyjgajbij+cGAn f6YRggUofSOctxq3TTm5WiH924ZY1TFLqKdB7g4AWIinM8xEH7sOK6R/TCWH2l8JzJ5k6C7L+wLmyJDCGu4flyMZECX/AZxkt8jP5wq7m8UcGSznF6U9KPF0fDZ0ITcL符合要求。 (3)设置弯起钢筋时,进行配计算。 根据已配钢筋Ear9i5jAatv8yEwNd9aiRg==,利用kPdEcTvtcShUtZGX6h1u2Q==以45°角弯起。 则弯起钢筋承受的剪力为: 0rpH9cLarijgbeVcn6UeutqTHE7tCaTONN2eKu9Htf5bDvvIAWd9qnWhduIdVlgl3sEnLpmy8NOKZYPeZ5ziHC61AGyiD7OWfifAV/SMr8jdhU/luFN/HEx+og6+OiB16x7i91WVDObKfBy78rsP68eVXsqyI8ItwYVczDKvyng= 混凝土和箍筋所承担的剪力 9lZGfAi0diKsZVIcuIJdSWFT9jAnx14UKKzXUNDd7H5ooqJ/Y7vO307xRJtmAnVPdrqubczaHWQYx4hAUF63FpLYqdqjkOnrIC+AdG67n1PTMiXdFhliexTL9x5SV0YD 故只需按照构造要求配置箍筋,选用双肢箍筋中8tlLMY/WhJwwsTkcd6r+nA==, +GWzFb7+kBe/VMcGBOPBgcp3DsBjRKc3If8f6l03DAQI/CiPszzU9AQIN3nT8pA8/97XWAy8McaA/EPmssf5rDFBYcXtKIbNegCFfNh6nXikqcV/tEnzqtbFfxXY1yLYx9a6iYmBc8y/AL8y666Cxmr7OQkMq7W/yIZxYdFDrC5lqvrgCaxITzx7bX0y1nN+k3Vx4DjWz2tALL1uI0XT8w== 验算弯起点斜截面受剪承载能力(弯起点离梁端净距为SCnvQ8khBrMntMQeyrJQNg==) tWgg/hELIf4qqrAnEbKlICOMi8XKm5yShIMRdwu8k21TxbATKbi/s1HJK85N/3J7SBXlZTZQUvkF8Awuj4ngtW5dRQaTE12bdQ3/ZCrz+Ls=,故满足要求