水泥浆胶凝引起的失重和气侵，国内外都进行了较深入的研究，证明了它的存在和严重程度。而水泥浆桥堵失重研究甚少。为此，在模拟实验的基础上，研究了水泥浆在有无泥饼情况下的桥堵失重和气侵规律。研究表明，泥浆形成的内、外泥饼，对水泥浆自由水渗入模拟地层和桥堵的形成起到了限制作用。不同井壁状况下，影响水泥浆桥堵失重的温度、失水量、压差等因素，其交互作用是不相同的。文中还对水泥浆胶凝失重气侵与桥堵失重气侵的特点和气侵压差值进行了对比和分析，并提出了防止失重和气侵的有关依据 Cement slurry caused by gravity loss and gas invasion, both at home and abroad conducted a more in-depth study to prove its existence and severity. However, there is little research on the loss of cement slurry bridge. For this reason, on the basis of the simulation experiment, the paper studies the weight loss and gas invasion of the bridge with and without mud cake. The results show that the mud cake formed inside and outside the mud cake, the free water slurry into the simulated formation and bridge plugging played a limiting role. Under different wellbore conditions, the interactions that affect the loss of weight, such as temperature, water loss and pressure drop, are not the same. The paper also compares and analyzes the characteristics of gas invasion of cementitious slurry gelled by gravity loss and the gas invasion pressure loss by bridge plugging, and puts forward the relevant evidences for preventing weight loss and gas invasion