- 摘 要
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（1 山東建筑大學土木工程學院， 濟南 250101；2 山東建筑大學工程鑒定加固研究院， 濟南 250013）
［摘要］針對砌體結構房屋加固改造中拆墻托換的問題，提出了一種新型的托換結構體系。首先對擬拆墻體上部采用外包角鋼加固形成鋼-砌體組合托梁，然后對上層墻體采用鋼筋網聚合物砂漿面層進行加固，組合托梁與加固后的上層墻體形成組合墻梁結構，形成托換結構體系。通過對4個試件的試驗研究得到：該托換結構的受力機理與砌體墻梁結構相同，可簡化為拱結構，加固后的上層墻體通過拱作用將荷載向兩端支座傳遞，角鋼和鋼筋網水平鋼筋為拉桿，減小了組合托梁的內力，提高了構件的承載力。托梁端部和上層墻體端部均設置構造柱，保證了上層墻體內鋼筋網水平鋼筋的錨固，避免了托梁支座處砌體局壓破壞。原墻體內是否有圈梁和角鋼大小對托換結構的承載力有一定影響。該托換體系墻體最終產生斜壓破壞，墻體的抗剪承載力可按照砌體墻梁墻體抗剪計算公式計算，但計算結果偏保守。
［關鍵詞］加固改造； 托換結構； 鋼-砌體組合梁； 墻梁； 托梁
中圖分類號：TU398.9文獻標識碼：A文章編號：1002-848X(2020)06-0046-05
Study on application of steel-masonry composite wall beam structure in transformation underpinning of masonry structure buildings
Zhang Yuming1,2， Guo Donghui1， Fang Xiaopeng1， Zhao Kaozhong1,2
(1 School of Civil Engineering, Shandong Jianzhu University, Jinan 250101, China；2 Engineering Research Institute of Appraisal and Strengthening, Shandong Jianzhu University, Jinan 250013, China)
Abstract:A new underpinning structural system was proposed for removing walls for underpinning in the reinforcement and transformation of masonry structure buildings. Firstly, the top part of the wall which would be moved was strengthened with external angle steels to form steel-masonry composite underpinning beams, and then the upper wall was strengthened with steel wire web-polymer mortar layer. The composite underpinning beam and the strengthened upper wall made up a composite wall beam structure, forming the underpinning structural system. The static test of four specimens was carried out. The test results show the mechanism of the underpinning structure is the same as the wall beam in masonry structures and can be simplified as arch structure. The strengthened upper wall transfers the load to the two supports by arch effect. The angle steels and the horizontal reinforcements are tensile bars to reduce the internal force of the composite underpinning beam and improve the bearing capacity of the member. The structural columns which are arranged at the end of the underpinning beam and the upper wall provide a good anchor for the horizontal reinforcements of the upper wall and can avoid the local pressure damage at the two supports of underpinning beam.The size of ring beam and angel steel in the wall has a certain influence on the bearing of the underpinning structure. The final failure mode is the diagonal-compression failure. The shear bearing capacity of the wall in this new style wall beam can be calculated in accordance with wall beam of masonry structures, but the calculation result is conservative.
Keywords:reinforcement and transformation; underpinning structure; steel-masonry composite beam;wall beam; underpinning beam
*國家重點研發(fā)計劃項目（2017YFC0702900）。
作者簡介：張玉明，博士，副教授，碩士生導師，一級注冊結構工程師，Email：13808920620@163.com。
