已知矩形截面梁b＝250mm，h＝600mm，采用C30级混凝土。<br/> 若受拉区配有4<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20251103/24130954_0.png">25＋4<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20251103/24130954_0_1.png">28纵向受力钢筋（HRB400级），如图所示单筋矩形截面梁，则此梁的受弯承载力Mu＝（　　）kN·m。<br/> <img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20251103/24130954_0_2.png">