低预应力混凝土实心方桩作抗拔桩的设计与应用  

Design and Application of Low-Prestressed Concrete Solid Square Pile as Uplift Pile

作　　者：王传坤 毛江鸿 辛大伟 高贯鹏 高溪溪 WANG Chuankun;MAO Jianghong;XIN Dawei;GAO Guanpeng;GAO Xixi(Qingdao Teng Yuan Design Institute CO.,LTD.,Qingdao 266100,China;Department of Civil Engineering,College of Architecture&Environment,Sichuan University,Chengdu 610065,China;The Fourth Construction CO.,LTD.,of China Construction Eighth Engineering Division,Qingdao 266100,China)

机构地区：[1]青岛腾远设计事务所有限公司,青岛266100 [2]四川大学建筑与环境学院土木工程系,成都610065 [3]中建八局第四建设有限公司,青岛266100

出　　处：《结构工程师》2023年第6期164-170,共7页Structural Engineers

基　　金：四川省重点研发科技项目(2022YFQ0048)。

摘　　要：低预应力混凝土实心方桩可用于腐蚀性环境下对单桩抗拔承载力需求不高的建筑工程。结合工程实例,介绍了低预应力实心方桩作抗拔桩存在的问题与解决方案。低预应力实心方桩作抗拔桩,应考虑不入岩的不利情况,并补充计算抗拉承载力设计值和一级裂缝控制的抗裂拉力标准值等关键参数。为对比验证接桩工艺的可靠性,开展了三组不同方桩的抗拔载荷试验。结果表明,端板厚度对焊接法的抗拔承载力起控制作用,若端板厚度不足会发生弯曲破坏,使接桩失效;而机械连接法可靠性好,可实现拔力的有效传递。在根数相同的情况下,与预应力高强实心方桩、灌注桩相比,低预应力实心方桩作抗拔桩具有更好的经济效益。本工程实例可为其他相似的工程设计提供参考。The low-prestressed concrete solid square pile can be applied in building project where the demand of uplift capacity of a single pile is not high in corrosive environment.Combined with an engineering example,this paper introduced the problems and solutions of low-prestressed solid square pile as uplift pile.The lowprestressed solid square pile was applied as uplift pile,which the unfavorable situation of not entering the rock was considered,and the key parameters such as the design value of tensile bearing capacity and the characteristic value of anti-crack tensile force for first-order crack control were calculated.The uplift loading tests of three groups of different square piles were carried out,in ordor to compare and verify the reliability of pile splice technology.The results show that,the thickness of the end plate controls the uplift bearing capacity of the welding method.If the thickness of end plate is not enough,the bending failure will occur and lead to the failure of pile splice,while the mechanical splicing method is reliable and can realize the effective transmission of pull-out force.Under the same root number,compared with prestressed high-strength solid square pile and cast-in-situ pile,the low-prestressed solid square pile as uplift pile has better economic benefit.This engineering example can provide reference for other similar engineering designs.

关 键 词：低预应力混凝土实心方桩 抗拔桩 焊接法 机械连接法 抗拔载荷试验 

分 类 号：TU473.1[建筑科学—结构工程]