In order to enhance the service hfe of hollowsteel for rock drill stem, the odd number side section shape hollowsteel has been designed.
为了提高凿岩钎杆用中空钢的使用寿命，设计了奇数边截面形状的中空钢。
2
The achievements in this paper may be referenced for the fire protection design of practical engineering with concrete filled steel rectangular hollowsection columns.
本文的研究成果可为有关矩形钢管混凝土工程进行抗火设计时提供参考。
3
The practice proved that strengthen prestressed hollow by method of section-steel bonded, safe and reliable, low investment, fast and interference small, the effect was very good.