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The inter-height ratio l 0 / h ≤ 5.0 simply supported reinforced concrete single-span beam or multi-span continuous beam is called deep flexural members. Has a huge bearing capacity of deep flexural members, thus not only widely used in construction, but also widely used in the waterway, harbor workers, railway, highway, municipal and other civil engineering field. The small deep flexural members across a high smaller loads moment, while the shear is relatively high, so well received by the the oblique section cracking of calculation is particularly important. Articles through by the oblique section cracking performance under concentrated loads of 10 popular member of the pilot study, the analysis of the main factors affect the performance of the oblique section cracking, the law of development of the oblique section failure pattern and diagonal crack widths, a deeply bend Charpy oblique section cracking shear formula. The article content and the main results are as follows: (1), the oblique section 10 under concentrated loads deeply bend Charpy cracking resistance test, analysis of the main factors of the impact oblique section cracking shear, failure pattern Beams and the law of development of diagonal crack widths. (2) oblique section cracking shear size decreases as the shear span ratio increases with the strength grade of concrete beam section size increases. Beams under concentrated loads across high than cracking shear is very small, almost negligible. (3) does not appear inclined cracks, Stirrups stress is almost zero, diagonal cracks appeared, the cracks intersect STIRRUPS stress suddenly increases, and finally reaches the yield. Therefore, it can be concluded that the oblique section cracking strength and abdominal reinforcement ratio has little. Abdominal reinforcement ratio in the control in the diagonal crack too wide, play an important role. (4) starting from the theory of elasticity, according to the strength of concrete in tension - compression stress state theory, the theoretical calculation of the deeply curved Beams cracking shear mode, and the mode regression test beam cracking shear analysis, while the guaranteed rate of 95% is given shear cracking utility formula, the formula shear cracking oblique section of deep flexural members to make a better estimate. Calculated by comparison of test results, the average V cr t / V cr c = 1.562, discrete coefficient C v = 0.381 Description formulas better compliance. This equation has the form of simple, clear physical meaning, in line with good advantages.
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