坝轴建基线的确定和基础开挖设计

微机重力坝ＣＡＤ系统中，根据河床地质情况和枢纽建筑物的布置，采用程序自动计算和设计人员参与相结合，确定坝轴建基线。程序中考虑了多种开挖要求，对各类坝段、护坦、厂房和尾水渠，可分类分层计算开挖方量，并汇总成枢纽总开挖量，同时，能给出各类坝段、护坦及厂房剖面的开挖线，以及河床开挖轮廓围线。

Determination of Base Line of Dam Axis and Foundation Excavation Design

In the micro computer CAD system for gravity dams, the base line of dam axis is determined by meansof programmed computing and designer's input combined, according to geological conditions of river bedsand layouts of project buildings. Considering various requirements of excavations, the programme can compute excavation quantities of different type of dam sections, aprons, power houses and tailrace channels bycatalogue at different level, and then sum them into the total excavation quantity. The programme can alsodraw excavation lines of dam sections. aprons. power houses. and power houses as well as planimetric linesof river bed excavation.