混凝土強(qiáng)度等級(jí)檢測(cè)(回彈試驗(yàn))回彈法檢測(cè)砼強(qiáng)度試用于工程結(jié)構(gòu)普通砼抗壓強(qiáng)度的檢測(cè)。砼強(qiáng)度值的確定分為如下幾個(gè)步驟：1、 回彈值測(cè)量 2、 2、碳化深度值測(cè)量 3、 3、回彈值計(jì)算 4、 4、砼強(qiáng)度的計(jì)算一、 回彈值測(cè)量1、 一般規(guī)定：結(jié)構(gòu)或物件砼強(qiáng)度檢測(cè)可采用下列兩種方式，其適用范圍及結(jié)構(gòu)或構(gòu)件數(shù)量應(yīng)符合下列規(guī)定：（1）、單個(gè)檢測(cè)：適用于單個(gè)結(jié)構(gòu)或構(gòu)件的檢測(cè)。（2）、批量檢測(cè)：適用于相同的生產(chǎn)工藝條件下，砼強(qiáng)度等級(jí)相同，原材料、配合比、成型工藝、養(yǎng)護(hù)條件基本一致且齡期相近的同類結(jié)構(gòu)或構(gòu)件，按批進(jìn)行檢測(cè)的結(jié)構(gòu)構(gòu)件。抽檢數(shù)量不得少于同批構(gòu)件總數(shù)的30%且不得少于10件。2、每一結(jié)構(gòu)或構(gòu)件的測(cè)區(qū)應(yīng)符合下列規(guī)定：（1）、每一結(jié)構(gòu)或構(gòu)件測(cè)區(qū)數(shù)量應(yīng)不少于10個(gè)。對(duì)某一方向尺寸小于4.5米，且另一方向尺寸小于0.3米的構(gòu)件其測(cè)區(qū)數(shù)量可適當(dāng)減少，但不應(yīng)少于5個(gè)。（2）、相鄰兩測(cè)區(qū)的間距應(yīng)控制在2米以內(nèi)。測(cè)區(qū)離構(gòu)件端部或施工縫邊緣的距離不宜大于0.5米，且不宜小于0.2米。（3）、測(cè)區(qū)應(yīng)選在使回彈儀處于水平方向檢測(cè)砼澆筑側(cè)面，當(dāng)不能滿足這一要求時(shí)，可使回彈儀處于非水平方向檢測(cè)砼強(qiáng)度澆筑側(cè)面、表面或底面。但回彈值需修正。（4）、測(cè)區(qū)宜選在構(gòu)件的兩個(gè)對(duì)稱可測(cè)面上，也可選在一個(gè)可測(cè)面上，且應(yīng)均勻分布。在構(gòu)件的重要部位及薄弱部位必須布置測(cè)區(qū)，并應(yīng)避開(kāi)預(yù)埋件。（5）、測(cè)區(qū)的面積不宜大于0.04。（6）、檢測(cè)面應(yīng)為砼表面，并應(yīng)清潔平整，不應(yīng)有疏松層、浮漿、油垢、涂層以及蜂窩、麻面。必要時(shí)可用砂輪清除疏松層和雜物，且不應(yīng)有殘留的粉末或碎屑。3、回彈值測(cè)定（1）、檢測(cè)時(shí)，回彈儀的軸線應(yīng)始終垂直于結(jié)構(gòu)或構(gòu)件的檢測(cè)面。緩慢施壓，準(zhǔn)確讀數(shù)，快速?gòu)?fù)位。（2）、測(cè)點(diǎn)宜在測(cè)區(qū)范圍內(nèi)均勻分布。相鄰兩測(cè)點(diǎn)的凈距不宜小于20mm。測(cè)點(diǎn)距外露鋼筋、預(yù)埋件的距離不宜小于30mm。測(cè)點(diǎn)不應(yīng)在氣孔或外露石子上，同一測(cè)點(diǎn)只應(yīng)彈一次，每一測(cè)區(qū)應(yīng)取16個(gè)回彈值。二、 碳化深度測(cè)量值1、 回彈值測(cè)量完畢后，應(yīng)在有代表性的位置上測(cè)量碳化深度值。測(cè)點(diǎn)不應(yīng)小于構(gòu)件測(cè)區(qū)數(shù)的30%，取其平均值為該構(gòu)件的每測(cè)區(qū)的碳化深度值，當(dāng)碳化深度最大值與最小值之差大于2.0mm時(shí)，應(yīng)在每一測(cè)區(qū)測(cè)量碳化深度。2、 碳化深度值測(cè)量，可采用適當(dāng)?shù)墓ぞ咴跍y(cè)區(qū)表面形成直徑約15mm孔洞，其深度應(yīng)大于砼的碳化深度?？锥粗械姆勰┖退樾紤?yīng)清除干凈，并不得用水擦洗。同時(shí)，應(yīng)采用濃度為1%的酚酞酒精溶液滴在孔洞內(nèi)壁的邊緣處。當(dāng)已碳化與未碳化界線清楚時(shí)再用深度測(cè)量工具測(cè)量已碳化與未碳化砼交界面到砼表面的垂直距離。測(cè)量應(yīng)不少于3次，取其平均值。每次讀數(shù)精確至0.5mm。碳化深度修正系數(shù)表 表1實(shí)測(cè)強(qiáng)度碳化深度d(mm)12345610-200.950.880.820.770.720.6820-300.940.860.800.740.700.6230-400.930.840.780.730.660.6040-500.920.820.760.720.650.6050-600.910.800.740.710.640.60三、 回彈值計(jì)算1、計(jì)算測(cè)區(qū)平均回彈值，應(yīng)該從該測(cè)區(qū)的16個(gè)回彈值中剔除3個(gè)最大值和3個(gè)最小值，求余下的10個(gè)回彈值的平均值，如果是水平方向回彈澆筑砼的側(cè)面，該值即為該測(cè)區(qū)平均回彈值Rm。如果不足，此值還需修正。2、 非水平方向檢測(cè)砼澆筑側(cè)面時(shí)， 應(yīng)按下列修正: Rm=Rm+Ra式中 Rm：非水平狀態(tài)檢測(cè)時(shí)測(cè)區(qū)的平均回彈值，精確到0.1Ra：非水平狀態(tài)檢測(cè)時(shí)回彈值修正值，可按本附表1采用。Rm：測(cè)區(qū)平均回彈值（修正后）非水平狀態(tài)檢測(cè)時(shí)回彈值修正值 表1測(cè)試角度檢測(cè)角度+90+60+45+30-30-45-60-9020-6.0-5.0-4.0-3.0+2.5+3.0+3.5+4.030-5.0-4.0-3.5-2.5+2.5+3.0+3.5+4.040-4.0-3.5-3.0-2.0+1.5+2.0+2.5+3.050-3.5-3.0-2.5-1.5+1.0+1.5+2.0+2.53、 水平方向檢測(cè)砼澆筑頂面或底面時(shí)， 應(yīng)按下列修正：Rm=+ Rm=+式中：Rm:測(cè)區(qū)修正后平均回彈值 ：水平方向檢測(cè)砼澆筑表面時(shí)，測(cè)區(qū)平均回彈值。：砼澆筑表面回彈值的修正值，見(jiàn)附表2。：水平方向檢測(cè)砼澆注底面時(shí)，測(cè)區(qū)平均回彈值。：砼澆筑底面回彈值的修正值。見(jiàn)附表24 當(dāng)檢測(cè)時(shí)回彈儀為非水平方向且測(cè)試面為非砼的澆筑側(cè)面時(shí)。應(yīng)先按附表1對(duì)回彈值進(jìn)行角度修正。再按附表2對(duì)修正后的值進(jìn)行澆筑面修正。即：先修正角度，再修正澆筑面。 不同澆筑面的回彈值修 表2或表面修正值()底面修正值()或表面修正值()底面修正值()20+2.5-3.040+0.5-1.025+2.0-2.5450-0.530+1.5-2.0500035+1.0-1.5四、砼強(qiáng)度的計(jì)算（平均強(qiáng)度）1、經(jīng)過(guò)以上砼回彈數(shù)值測(cè)量?；貜棓?shù)值修正。碳化深度測(cè)量后，可利用平均回彈修正數(shù)值（Rm）及平均碳化深度（dm）,查附表3,可求得各個(gè)測(cè)區(qū)砼強(qiáng)度換算值。2根據(jù)各個(gè)測(cè)區(qū)的砼強(qiáng)度換算值可計(jì)算測(cè)區(qū)砼強(qiáng)度平均值。當(dāng)測(cè)區(qū)數(shù)為10個(gè)及以上時(shí)，應(yīng)計(jì)算強(qiáng)度標(biāo)準(zhǔn)差，平均值及標(biāo)準(zhǔn)差應(yīng)按下式計(jì)算： ，式中：結(jié)構(gòu)或構(gòu)件測(cè)區(qū)砼強(qiáng)度換算值的平均值。n：對(duì)于單個(gè)檢測(cè)的構(gòu)件，取一個(gè)構(gòu)件的測(cè)區(qū)數(shù)；對(duì)批量檢測(cè)的構(gòu)件，取被抽檢構(gòu)件的測(cè)區(qū)之和。：測(cè)區(qū)砼強(qiáng)度換算值。：結(jié)構(gòu)或構(gòu)件測(cè)區(qū)砼強(qiáng)度換算值的標(biāo)準(zhǔn)差。3、 結(jié)構(gòu)或構(gòu)件砼強(qiáng)度推定值（）的計(jì)算：結(jié)構(gòu)或構(gòu)件的砼強(qiáng)度推定值即是砼強(qiáng)度值，是指相應(yīng)于強(qiáng)度換算值總體分布中保證率不低于95%的結(jié)構(gòu)或構(gòu)件中的砼抗壓強(qiáng)度值。即：查表或據(jù)測(cè)強(qiáng)度曲線得出的強(qiáng)度換算值中有95%的值小于砼強(qiáng)度指定值。（1）、當(dāng)該結(jié)構(gòu)或構(gòu)件測(cè)區(qū)數(shù)少于10個(gè)時(shí)，強(qiáng)度推定值取強(qiáng)度換算值中最小的1個(gè)。即=min()(2)、當(dāng)該結(jié)構(gòu)或構(gòu)件的測(cè)區(qū)強(qiáng)度值中出現(xiàn)小于10.0Mpa這個(gè)數(shù)值時(shí)，砼強(qiáng)度值指定值則取小于10.0Mpa。即<10.0Mpa這個(gè)數(shù)值一般不出現(xiàn)。在測(cè)強(qiáng)度曲線和換算值表中也查不到，所以當(dāng)出現(xiàn)砼強(qiáng)度換算值<10.0Mpa時(shí)。砼強(qiáng)度推定值不用計(jì)算，直接取<10.0Mpa。（3）、當(dāng)該結(jié)構(gòu)或構(gòu)件測(cè)區(qū)數(shù)不少于10個(gè)或按批量檢測(cè)時(shí)，砼強(qiáng)度推定值：砼強(qiáng)度換算值 表3平均回彈值平均碳化深度值dm(mm)Rm00.511.522.533.544.555.562010.310.120.210.510.31020.410.710.510.220.61110.810.410.120.811.21110.610.32111.411.210.810.51021.211.611.41110.710.221.411.811.611.210.910.41021.61211.811.41110.610.221.812.312.111.711.310.810.510.12212.512.211.911.51110.610.222.212.712.412.111.711.210.810.41022.41312.712.41211.41110.710.31022.613.212.912.512.111.611.210.810.410.222.813.413.112.712.311.811.41110.610.32313.713.41312.612.111.611.210.810.510.123.213.913.613.212.812.211.811.41110.710.31023.414.113.813.41312.41211.611.210.910.410.223.614.414.113.713.212.712.211.811.411.110.710.410.123.814.614.313.913.412.812.41211.511.210.810.510.22414.914.614.213.713.112.712.211.811.51110.710.410.124.215.114.814.313.913.312.812.411.911.611.210.910.610.324.415.415.114.614.213.613.112.612.211.911.411.110.810.424.615.615.314.814.413.713.312.812.31211.511.210.910.624.815.915.615.114.61413.51312.612.211.811.411.110.72516.215.915.414.914.313.813.312.812.51211.711.310.925.216.416.115.615.114.413.913.41312.612.111.811.51125.416.716.415.915.414.714.213.713.212.912.41211.711.225.616.916.616.115.714.914.413.913.41312.512.211.811.325.817.216.916.315.815.114.614.113.613.212.712.41211.52617.517.216.616.115.414.914.413.813.51312.612.211.626.217.817.416.916.415.715.114.61413.713.212.812.411.826.41817.617.116.615.815.314.814.213.913.31312.61226.618.317.917.416.816.115.61514.414.113.513.212.812.1Rm00.511.522.533.544.555.5626.818.618.217.717.116.415.815.314.614.313.813.412.912.32718.918.51817.416.616.115.514.814.61413.613.112.427.219.118.718.117.616.816.215.71514.714.113.813.312.627.419.41918.417.81716.415.915.214.914.31413.412.727.619.719.318.71817.216.616.115.415.114.514.113.612.927.82019.61918.217.416.816.315.615.314.714.213.7132820.319.719.218.417.61716.515.815.414.814.413.913.228.220.62019.518.617.817.216.71615.61514.61413.328.420.920.319.718.81817.416.916.215.815.214.814.213.528.621.220.62019.118.217.617.116.41615.41514.313.628.821.520.920.219.418.517.817.316.616.215.615.214.513.82921.821.120.519.618.718.117.516.816.415.815.414.613.929.222.121.420.819.91918.317.71716.61615.614.814.129.422.421.721.120.219.318.617.917.216.816.215.81514.229.622.72221.320.419.518.818.217.51716.41615.114.429.82322.321.620.719.819.118.417.717.216.616.215.314.53023.322.621.9212019.318.617.917.416.816.415.414.730.223.622.922.221.220.319.618.918.217.61716.615.614.930.423.923.222.521.520.619.819.118.417.817.216.815.815.130.624.323.622.821.920.920.219.418.71817.5171615.230.824.623.923.122.121.220.419.718.918.217.717.216.215.43124.924.223.422.421.420.719.919.218.417.917.416.415.531.225.224.423.722.721.720.920.219.418.618.117.616.615.731.425.624.824.1232221.220.519.718.918.417.816.915.831.625.925.124.323.322.321.520.719.919.218.61817.11631.826.225.424.623.622.521.72120.219.418.918.217.316.23226.525.724.923.922.82221.220.419.619.118.417.516.432.226.926.125.324.223.122.321.520.719.919.418.617.716.632.427.226.425.624.523.422.621.820.920.119.618.817.916.832.627.626.825.924.823.722.922.121.320.419.91918.11732.827.927.126.225.12423.222.321.520.620.119.218.317.23328.227.426.525.424.323.422.621.720.920.319.418.517.433.228.627.726.825.724.623.722.92221.220.519.618.717.633.428.92827.12624.92423.122.321.420.719.818.917.833.629.328.427.426.425.224.223.322.621.720.92019.11833.829.628.727.726.625.424.423.522.821.921.120.219.318.2343029.12826.825.624.623.72322.121.320.419.518.334.230.329.428.32725.824.823.923.222.321.520.619.718.4Rm00.511.522.533.544.555.5634.430.729.828.627.2262524.123.422.521.720.819.818.634.631.130.228.927.426.225.224.323.622.721.9212018.834.831.430.529.227.626.425.424.523.822.922.121.220.2193531.830.829.62826.725.824.82423.222.321.420.419.235.232.131.129.928.227262524.223.422.521.620.619.435.432.531.530.228.627.326.325.424.423.722.821.820.819.635.632.931.930.62927.626.625.724.72423222119.835.833.332.33129.328272602524.323.322.221.23633.632.631.229.628.227.226.225.224.523.522.421.420.236.2343331.629.928.627.526.525.524.823.822.621.620.436.434.433.43230.328.927.926.825.825.124.122.821.820.636.634.833.832.430.629.228.227.126.125.424.4232220.936.835.234.132.73129.628.527.526.425.724.623.222.221.13735.534.43331.229.828.827.726.625.924.823.422.421.337.235.934.833.431.630.229.12826.926.225.123.722.621.537.436.335.233.831.930.529.428.327.226.525.42422.921.837.636.735.634.132.330.829.728.627.526.825.724.223.12237.837.13634.532.631.23028.927.827.12624.523.422.33837.536.434.93331.530.329.228.127.426.224.823.622.538.237.936.835.233.431.830.629.528.427.726.52523.922.738.438.337.235.633.732.130.929.828.72826.825.324.12338.638.737.53634.132.431.230.12928.32725.524.423.238.839.137.936.434.432.731.530.429.328.527.225.824.623.53939.538.236.734.73331.830.629.628.827.42624.823.739.239.938.5373533.332.130.829.82927.626.2252439.440.338.837.335.333.632.4313029.227.826.425.224.239.640.739.137.635.633.932.731.230.229.42826.625.424.439.841.239.63835.934.23331.430.529.728.226.825.624.74041.639.938.336.234.533.331.730.83028.42725.82540.24240.338.636.534.833.63231.130.228.627.32625.240.442.440.73936.935.133.932.331.430.528.827.626.225.440.642.841.139.437.235.434.232.631.730.829.127.826.525.740.843.341.639.837.735.734.532.93231.229.428.126.8264143.74240.2383634.833.232.331.529.728.427.126.241.244.142.340.638.436.335.133.532.631.83028.727.326.541.444.542.740.938.736.635.433.832.93230.328.927.626.741.64543.241.439.236.935.734.233.332.430.629.227.92741.845.443.641.839.537.23634.533.632.730.929.528.127.2Rm00.511.522.533.544.555.564245.944.142.239.937.636.334.9343331.229.828.527.542.246.344.442.640.33836.635.234.333.331.530.128.727.842.446.744.84340.638.336.935.534.633.631.830.4292842.647.245.343.441.138.737.335.934.93432.130.729.328.342.847.645.743.841.43937.636.235.234.332.430.929.528.64348.146.244.241.839.43836.635.634.632.731.329.828.943.248.546.644.642.239.838.336.935.934.93331.530.129.143.4494745.142.640.238.737.236.335.333.331.830.429.443.649.447.445.44340.53937.536.635.633.632.130.629.643.849.947.945.943.440.939.437.936.935.933.932.430.929.94450.448.446.443.841.339.838.337.336.334.332.831.230.244.250.848.846.744.241.740.138.637.636.634.53331.530.544.451.349.247.244.642.140.5393836.934.933.331.830.844.651.749.647.64542.440.839.338.337.235.233.632.13144.852.250.14845.442.841.239.738.637.635.533.932.431.34552.750.648.545.843.241.640.13937.935.834.332.731.645.253.251.148.946.343.64240.439.438.336.234.63331.945.453.651.549.446.64442.340.739.738.636.434.833.232.245.654.151.949.847.144.442.741.1403936.835.233.532.545.854.652.450.247.544.843.141.540.439.337.135.533.932.8465552.850.647.945.243.541.940.839.737.535.834.233.146.255.553.351.148.345.543.842.241.14037.736.134.433.346.45653.851.548.745.944.242.641.440.338.136.434.733.646.656.554.25249.246.344.642.941.840.738.436.73533.946.85754.752.449.646.74543.342.24138.83735.334.24757.555.252.95047.245.243.742.641.439.137.435.634.547.25855.753.450.547.645.844.142.941.839.437.73634.847.458.556.253.850.94846.244.543.342.139.83836.335.147.65956.654.351.348.446.644.843.742.540.138.436.635.447.859.557.154.751.848.84745.24442.840.538.736.935.7486057.655.252.249.247.445.644.443.240.83937.23648.25855.752.649.647.84644.843.641.139.337.536.348.458.656.153.15048.246.445.143.941.539.637.836.648.65956.653.550.448.646.745.544.341.84038.136.948.859.557.15450.94947.145.944.642.240.338.437.2496057.554.451.349.447.546.24542.540.638.837.549.25854.851.749.847.946.645.442.84139.137.849.458.555.352.150.248.347.145.843.241.339.438.2Rm00.511.522.533.544.555.5649.658.955.752.550.648.747.446.243.641.739.738.549.859.456.2535149.147.846.543.94240.138.85059.956.753.451.449.548.246.944.342.340.439.150.257.153.851.949.948.547.244.642.640.739.450.457.654.352.350.34947.745434139.750.65854.752.750.749.44845.443.441.44050.858.555.153.151.149.848.445.743.741.740.3515955.653.551.550.148.846.144.14240.751.259.4565451.950.549.246.444.442.34151.459.956.454.452.350.949.646.844.742.741.351.656.954.852.751.35047.245.14341.651.857.355.253.151.750.347.545.443.341.85257.855.753.652.150.747.945.843.742.352.258.256.15452.551.148.346.24442.652.458.756.554.45351.548.746.544.44352.659.15754.853.451.94946.944.743.352.859.657.455.253.852.349.447.345.143.6536057.855.654.252.749.847.645.443.953.258.356.154.653.150.24845.844.353.458.756.55553.550.548.346.144.653.659.256.955.453.950.948.746.444.953.859.657.355.854.351.34946.845.35457.856.354.751.749.447.145.654.258.256.755.152.149.847.54654.458.657.155.652.550.247.946.354.659.157.55652.950.548.246.654.859.557.956.453.250.948.5475559.958.456.853.651.348.947.355.258.857.25451.649.347.755.459.257.654.45249.64855.659.75854.852.45048.455.858.555.252.850.348.75658.955.653.250.749.156.259.35653.551.149.456.459.756.453.951.449.856.656.854.351.850.156.857.254.752.250.55757.655.152.550.8Rm00.511.522.533.544.555.5657.25855.552.951.257.458.455.953.351.657.658.956.353.751.957.859.356.75452.35859.75754.452.758.257.454.85358.457.855.253.458.658.255.653.858.858.655.954.1595956.354.559.259.456.754.959.459.857.155.259.657.555.659.857.9566058.356.4