混凝土纵向围堰控制爆破拆除及减震措施

在爆破拆除厂房和河中混凝土纵堰的过程中 ,必须对邻近重要的构筑物以及非拆除的坝体进行保护。为此 ,通过爆破试验获取k、α值 ,并利用公式v=k(Q1/3/R) α 预估最大单响药量 ;同时 ,通过爆破试验对减震孔、预裂缝的减震效果 ,它们的联合减震作用 ,以及结构缝 (内填 2cm厚的泡沫塑料板 )的减震效果进行了检验。试验结果表明 ,减震孔和预裂缝的联合减震作用以及结构缝的减震效果最为明显。由于采取了上述减震措施 ,并对爆破拆除全过程进行监测 ,使被保护目标处的质点振速均控制在允许的范围内

DEMOLITION OF LONGITUDINAL CONCRETE COFFERDAMS BY CONTROLLED BLASTING AND VIBRATION-DAMPING MEASURES

In the process of demolishing the longitudinal concrete cofferdams in factory area and river by controlled blasting,the important structures and non demolished dam body must be protected For this reason, the values of k and α are gained through blasting tests and the maximum charge weight per delay interval is pre estimated by use of the formula  v=k(Q 1/3 /R) α  At the same time,the damping effects of vibration damping holes and/or presplit crack as well as structural cracks(in which the foam plastic plate with 2cm thickness is filled)are examined by blasting tests The test results have shown that the damping effects of the structural cracks and presplit crack combined with vibration damping holes are the most remarkable Because of the above measures and the all round monitoring to blasting vibration,the particle vibration velocities at positions of the objects to be protected are controlled over a range of permission