Comparative Study on Design of Exposed Penstock Laid on Ground Using Chinese and American Specifications

Abstract

In this paper, differences by using selected three typical specifications—DL/T 5141-2001 (Chinese), ASCE No.79 in the version of 1993(American) and ASCE No.79 in the version of 2012 (American)—in structural design of exposed steel penstock were explored. A practical example about exposed penstock laid on ground applied in hydropower station was also used to analyze specifications clearly. The result shows that the main differences between Chinese and American specifications are allowable stress and load combination. The former is direct factor of calculating exposed penstock shell thickness. Therefore, ASCE No.79 (2012) designs the minimum wall thickness, followed by DL/T 5141-2001 and the last is ASCE No.79 (1993), which is correspondingly contrary to sort by allowable stress. Basically, ASCE No.79 (2012) defines lower safety coefficient for exposed penstock, which is identical with authoritative rules of pressure vessels in the U.S.A and EU. The safety of DL/T 5141-2001 has been proved via rich engineering experience and this specification is recommended for Chinese projects. Besides, ASCE No.79 (2012) is recommended.