采用橡皮膜的柔性封閉止水方法，解決了水泥土側(cè)壁止水問題；利用反壓力對水泥土滲透性大小可控制水頭差，并且可獲得較高水頭壓力；當(dāng)對其試樣施加周圍壓力進(jìn)行止水時，試樣會產(chǎn)生一定的變形和一定的超孔隙水壓力。水泥土滲透試驗(yàn)儀:結(jié)構(gòu)合理，操作簡便，自動加壓、恒壓保持，試驗(yàn)室理想的儀器設(shè)備。結(jié)構(gòu)及指標(biāo)：                                                                                                                                         1、加壓裝置：加壓氣源應(yīng)能使水壓按照規(guī)定要求穩(wěn)定地作用在試件上。                                                  2、滲透裝置：由滲透試模，透水石和濾紙組成。                                                                                        3、量程：0-2.5Mpa                                                                                                                                                 4、試模尺寸：70mm×80mm×40mm                                                                                                           5、試驗(yàn)密封材料：水泥加黃油密封材料水泥土滲透試驗(yàn)儀操作過程：                                                     1、試樣裝在底座上，試樣側(cè)壁涂薄層凡士林，試樣外側(cè)套橡皮膜；土試樣上、下部裝透水石。
2、將滲水管連接在測滲透流量管中；                                                                                                            3、水管給壓力室加壓力σ3；                                                                                                                                  4、水管加反壓力σb；                                                                                                                                           5、間隔Δt測讀滲透流量管滲出水量，同時測量水溫T；6、根據(jù)達(dá)西定理，計(jì)算試樣的滲透系數(shù)。