884aa四虎影成人精品,99久久国产综合精品女图图等你,97在线观看永久免费视频,久久精品国产精品亚洲38,ⅵdeodesetv性欧美

(山東省建筑科學(xué)研究院有限公司， 濟(jì)南 250031)

［摘要］通過(guò)沿跨度方向增加配置螺旋肋鋼絲并施加預(yù)應(yīng)力，提出預(yù)制預(yù)應(yīng)力混凝土板式樓梯和梁式樓梯。對(duì)6塊預(yù)制混凝土樓梯構(gòu)件開(kāi)展了靜力加載試驗(yàn)，包括3塊板式樓梯和3塊梁式樓梯，得到其破壞特征、開(kāi)裂荷載、撓度曲線及應(yīng)變分布等。結(jié)果表明：增加螺旋肋鋼絲并施加預(yù)應(yīng)力后，板式樓梯和梁式樓梯的抗裂性能均得到顯著改善，其承載能力均提升25%以上；在適當(dāng)減少普通鋼筋用量后，板式樓梯和梁式樓梯的抗裂性能和承載能力也得以提升。與普通鋼筋混凝土板式樓梯相比，預(yù)應(yīng)力混凝土梁式樓梯實(shí)現(xiàn)降低自重25%以上。對(duì)比構(gòu)件理論計(jì)算結(jié)果與試驗(yàn)結(jié)果得出，采用混規(guī)設(shè)計(jì)公式得到的預(yù)制預(yù)應(yīng)力混凝土樓梯的開(kāi)裂彎矩和極限彎矩計(jì)算值均小于試驗(yàn)值，誤差在10%內(nèi)，滿足實(shí)際工程精度要求。 

［關(guān)鍵詞］預(yù)制樓梯；板式樓梯；梁式樓梯；預(yù)應(yīng)力混凝土；足尺試驗(yàn)；抗彎性能 

中圖分類號(hào)：TU378-5 文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1002-848X(2021)16-0008-08

Experimental research on flexural behavior of precast prestressed concrete stairs 

LIU  Wenzheng,  CUI  Shiqi 

(Shandong Provincial Academy of Building Research Co., Ltd., Jinan 250031， China) 

Abstract: By adding spiral rib steel wires along the span direction and applying prestress, precast prestressed concrete slab stairs and beam stairs were proposed. Static loading tests were carried out on 6 precast concrete stair components, including 3 slab stairs and 3 beam stairs, and their failure characteristics, cracking load, deflection curve and strain distribution were obtained. The results show that after adding spiral rib steel wires and applying prestress, the crack resistance of slab stairs and beam stairs are significantly improved, and their load-bearing capacity is increased by more than 25%; after appropriately reducing the amount of ordinary steel, the crack resistance and bearing capacity of the slab stairs and beam stairs have also been improved. Compared with ordinary reinforced concrete slab stairs, prestressed concrete beam stairs can reduce their own weight by more than 25%. Comparing the theoretical calculation results of the components with the experimental results, it is concluded that the calculated values of the cracking and ultimate bending moments of the precast prestressed concrete stairs obtained by the mixed-plan design formula are less than the experimental values, and the error is within 10%, which meets the actual engineering accuracy requirements. 

Keywords:precast stairs； slab stair; beam stair; prestressed concrete； full-scale test； flexural behavior

*山東省墻材專項(xiàng)基金項(xiàng)目（魯財(cái)建指〔2014〕139號(hào)），山東省住房和城鄉(xiāng)建設(shè)廳科學(xué)技術(shù)項(xiàng)目（2018-K9-01）。

 作者簡(jiǎn)介：劉文政，博士，正高級(jí)工程師，Email: liuwenzheng1986@163.com。