試驗研究 2025年 第卷 第18期
DOI: 10.7672 / sgjs2025180154
免支撐鋼筋桁架混凝土疊合板底板施工階段受力性能試驗研究
吳自清
作者簡介：
吳自清，高級工程師，E-mail:156893856@ qq. com作者單位：
中鐵一局集團有限公司，陜西西安 710054基金項目：
?陜西省重點研發(fā)計劃專項（ 2022LL-JB-10）；中鐵一局集團有限公司科技計劃項目（JA2024B207）；陜西省省級國有資本經(jīng)營預算科技創(chuàng)新專項資金項目（ZXZJ-2024-015）摘要：
為解決鋼筋桁架混凝土疊合板底板施工階段易開裂、需大量豎向支撐難題，提出了采用三角型鋼的免支撐措施，并對免支撐鋼筋桁架混凝土疊合板底板試件進行了施工階段的靜力加載試驗，考慮是否采取免支撐措施和板跨影響，獲得試件破壞現(xiàn)象和荷載-跨中撓度曲線，分析板底縱筋和三角型鋼的應變變化規(guī)律。結(jié)果表明，采取免支撐措施后可顯著提高樓承板剛度，減小板底鋼筋應變，在板跨與免支撐措施適配時，板底不開裂且跨中撓度不超限，可達到免支撐效果；免支撐鋼筋桁架混凝土疊合板底板的板底縱筋受拉、三角型鋼受壓，在施工階段均不屈服；隨著板跨增大，板底縱筋和三角型鋼的應變均增大。
English：
In order to solve the problem that the free-support steel bar truss laminated concrete slab floorin construction stage is easy to crack and needs a lot of vertical support, a free support measure usingtriangular section steel is proposed. Static tests are carried out on the free-support steel bar trusslaminated concrete slab floor in construction stage. The effect of free support measure and slab span isconsidered. The failure phenomenon and curves between load and mid-span deflection are obtained, andthe change law of the strain between the slab-bottom longitudinal bar and the triangular section steel isanalyzed. Test results show that the adoption of free support measure can obviously improve the stiffnessof floor deck and decrease the strain of steel bar at the bottom of slab, and when the slab span and thefree support measure are adaptive, there is no crack at the bottom of slab and the mid-span deflection isless than the limit, indicating that the free support measure has good application effect. The slab-bottomlongitudinal bar and the triangular section steel are in tension and compression respectively, and the bothdo not yield in construction stage. As the slab span increasing, the strain of the slab-bottom longitudinalbar and the triangular section steel increases.