重大工程已成为我国科技创新的重要平台，但由于创新过程复杂、投入大、风险高，以设计单位、施工单位为主的承包商作为核心主体在创新过程中积极性不高，造成工程领域技术进步缓慢、创新投入产出效率低，重大工程远未体现其创新驱动功能。为此，选取青藏铁路、港珠澳大桥、杨房沟水电站为案例，结合专家访谈对重大工程创新实践进行挖掘，基于“动机-机会-能力”（MOA）理论，从动机、能力、机会3个维度对承包商创新行为关键驱动因素进行分析提炼，构建重大工程承包方创新行为的前因机制模型。结果表明，制度压力和工程本身复杂性是承包方创新的直接驱动力，知识基础和吸收能力为其创新活动提供重要支撑，业主支持和创新网络结构则构成承包方创新行为的机会条件。因此，为有效激发重大工程中承包商创新行为，政府和业主方要遵循压力与动力并举的原则强化承包商创新动机，不断完善承包商创新能力的培养和提升，并加大对承包商创新行为的资源支持。

Megaprojects are now a crucial platform for scientific innovation. However, contractors (mainly including designers and constructors) are not strongly motivated as key subjects in the innovation process due to the features of complexity, enormous investment and high risk of megaprojects. So megaprojects are far from exhibiting their inventive driving functions as a result of slow technical advancement and low efficiency of innovation input and output. Therefore, with the help of expert interviews and taking the Qinghai Tibet Railway, Hong Kong Zhuhai Macao Bridge, and Yangfanggou hydropower station as examples, this paper analyzes and refines the key driving factors of contractors’ innovation behavior from three dimensions, i.e. motivation, capability and opportunity, and then builds the antecedent mechanism model about innovation behavior of contractors in megaprojects based on the motivation-opportunity-ability (MOA) theory. The findings demonstrate that the institutional pressure and the complexity of the megaprojects itself are the direct driving forces for the contractors' innovation. In addition, the knowledge base and the absorptive capacity play a significant role in supporting the contractors' innovation activities, and the owner's support and the structure of the innovation network make up the situational conditions. Therefore, in order to effectively stimulate the innovative behavior of contractors in megaproject, the government and the owners should follow the principle of both pressure and motivation to strengthen the innovative motivation of contractors, constantly improve the cultivation and promotion of contractors' innovative ability, and increase resource support for the innovative behavior of contractors.

F284；G301

国家社会科学基金后期资助项目“重大工程交易治理理论与方法”（19FJYB004）；安徽省自然科学基金项目“水科学”联合基金项目“重大水利工程建设管理机制与技术研究”（2208085US19）