为使商用车发动机及其附件产品在开发过程中满足用户实际使用环境下的载荷强度需求，避免出现过考核或欠考核的问题，进行了商用车发动机振动试验载荷谱研究。首先，对某型号发动机进行用户画像场景工况分析和载荷谱测试，获得模拟用户使用道路及试验场强化道路等工况下的振动数据；其次，对测试数据进行频谱分析和容差上限估计，采用工程截取法进行周期随机振动的信号分离；最后，基于载荷谱归纳理论和损伤等效理论得到发动机及其附件的实测加速验证载荷谱，并与ISO 16750标准进行对比分析。研究结果表明：实测归纳载荷谱与ISO标准谱在谱型上基本相似，但振动频率和量值上存在一定差异；按照实测谱进行台架验证时间为94 h、等效寿命120万 km的加速计算，得到其纵向、横向和垂向的振动能量有效值，分别为169.3 m/s²，171.3 m/s²和172.9 m/s²。实测加速谱将三个加载方向的振动水平分开归纳，更符合产品实际应用情况。本研究可为更加有效地制定发动机产品振动耐久试验规范、合理评价其可靠性与耐久性提供参考。

To ensure that commercial vehicle engines and the auxiliary components meet load intensity requirements reflective of actual user operational scenarios during development, thereby preventing over-testing or under-testing issues, an integrated systematic framework was established. First, scenario-based user profile analysis and load spectrum testing were implemented on a specific engine model, capturing vibration data under simulated real-user road conditions and accelerated test-track environments. Subsequently, spectral analysis and tolerance upper-bound estimation were conducted on the measured data, and periodic-random vibration signals separation was performed with an engineering truncation method. Finally, an accelerated validation load spectrum for engines and accessories was synthesized based on load spectrum generalization theory and damage equivalence principles, followed by comparative analysis against ISO 16750 standards. The results show the synthesized load spectrum exhibits similar spectral shape to that of ISO standard but differs in frequency ranges and amplitude distributions. The acceleration calculation was carried out according to the measured spectrum with a bench validation duration of 94 hours and a lifespan of 1.2 million kilometers. The root mean square (RMS) vibration energy values achieved in the longitudinal, lateral, and vertical loading directions are 169.3 m/s², 171.3 m/s², and 172.9 m/s², respectively. Independent characterization for vibration levels across three loading directions of the measured acceleration spectrum can better reflect the actual application conditions of product. This study presents a validated methodology for optimizing vibration durability test specifications and improving reliability and durability assessments of engine systems.