Proposal of steel Column Bases Solidified with RC Stub Covered with Steel Tubing and Tests the Characteristics.

提出了一种新的钢柱脚构造方法-外包钢管混凝土柱脚。为了明确柱脚的受力特性，对24个柱脚试件进行了水平荷载作用下的试验研究。试验的主要参数为钢筋混凝土柱的高度、埋深、混凝土的抗压强度和主筋的布置。1.高强混凝土柱脚的钢筋混凝土短柱体积虽小，但其受力性能良好。2.许多试件的屈服强度是由钢筋的屈服决定的。但也有部分短柱混凝土强度较低的试件，其锚固破坏是由钢筋锚固破坏决定的。3.钢管的存在有助于钢柱向钢筋混凝土短柱的应力传递。

A new structural method of steel column bases, which solidified with RC stub covered with steel tubing, was proposed. This method has good construction workability.In order to clarify the mechanical characteristics of the proposed column bases, 24 specimens were tested under alternating horizontal load. The main parameters involved in the tests were height and covering depth of RC stub, compressive strength of concrete and arrangement of reinforcing main bar.Some observations from the test results are as follows. 1. The column bases with high strength concrete were good mechanical characteristics in spite of small RC stub. 2. The yielding strength of many specimens were decided by yielding of reinforcing bar. But some specimens, which solidified with low stub consist of low strength concrete, were decided by failure of anchorage of reinforcing bar. 3. The steel tubing contributes to stress transfer from steel column to RC stub.