重锤夯实抛石基床的有效加固深度试验研究

Experimental research on effective reinforced depth of rubble bed with heavy tamping compaction

重锤夯实法是抛石基床夯实施工中的一种传统方法,然而由于其夯击能量小,基床分层厚度小,导致施工效率低下。为此,提出对传统重锤夯实工艺进行改进,即采用超重锤以及较大的基床分层厚度的施工工艺。首先设计了超重夯锤,并通过现场的夯击瞬时应力对比测试试验以及室内模型试验,证明了新工艺的可行性。在此基础上,将重锤夯实基床分层厚度从传统的每层2m提高至4m。厦门港嵩屿港区抛石基床的夯实施工结果表明,改进后的重锤夯实工艺效果较好,平均夯沉率达到了14.85%,而且施工效率显著提高,为类似工程提供了借鉴。

Heavy tamping compaction is a traditional method in tamping construction of rubble bed. Some constraints in this method, such as small tamping energy and small dividing thickness, result in the low efficiency. A couple of improvements in the process of heavy tamping compaction are put forward. The proposed improvements are the increase in the tamping energy and the dividing thickness of rubble bed. Heavy hammer is first designed; then field contrast test of tamping stress and laboratory model test are carried out. The test results show that the new process is feasible. On this basis, the dividing thickness of rubble bed is increased to 4 m from 2 m. The construction results of the Songyu Harbour in Xiamen show that the improved process of heavy tamping compaction gets a good result; as the average compacting rate reaches as high as 14.85% and the efficiency increases significantly, so as to provide reference for similar engineering practice.