抗震设防烈度为8度的6层砖墙承重住宅建筑，有关设置钢筋混凝土构造柱的措施，哪一条不恰当（）

A.在外墙四角及宽度大于2m的洞口应设置构造柱

B.在内墙与外墙交接处及楼梯间横墙与外墙交接处应设置构造柱

C.构造柱最小截面为240mm×180mm，构造柱与砖墙连接处砌成马牙槎并沿墙高每隔500mm设2φ6的钢筋拉结，每边伸人墙内1m

D. 构造柱应单独设置柱基础

University Physics is intended for students of science and engineering. Primary emphasis is on physical principles and problem- (46) ; historical background and specialized practical applications have been given a place of (47) importance. Many worked-out examples and an extensive collection of problems are included within each chapter.

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50（）