抗拔桩依据结构特性有效承担了结构上拔荷载，成为解决抗浮问题的有效措施。精确获取抗拔桩内力是了解其承载特性的关键，但混凝土抗拉性能较差，当荷载达到一定量级后，导致其弹性模量降低，传统轴力计算方法不再适用。基于光频域反射技术（optical frequency domain reflectometry, OFDR）应变测量技术，通过抗拔桩室内模型试验，分析拉拔过程中钢筋和混凝土的应变分布和演化规律，获取受拉-破坏全过程混凝土弹性模量变化情况，提出利用混凝土应变与弹性模量关系曲线优化轴力计算方法，精准获取桩身轴力，并应用于实际工程。试验结果表明：在小荷载情况下，OFDR技术可以根据桩身应变曲线定位混凝土裂缝产生位置；大荷载桩身破坏情况下，可以利用应变与弹模关系曲线修正混凝土弹模，对混凝土轴力进行修正，相对传统计算方式可将全过程轴力相对误差控制在5%以内，实际工程验证了该方法的可行性，优化后的轴力计算具有更高的精确度。

Uplift piles, in accordance with their structural properties, effectively sustain the structural uplift loads and have emerged as an efficacious solution to address the anti-floating issue. The precise determination of the internal forces within uplift piles is crucial for comprehending their load-bearing characteristics. Nevertheless, the tensile capacity of concrete is relatively feeble. Once the load attains a specific magnitude, its elastic modulus will decline, rendering the traditional axial force calculation methods inapplicable. By leveraging the optical frequency domain reflectometry(OFDR) strain measurement technology and conducting indoor model tests of uplift piles, the strain distribution and evolution patterns of both steel bars and concrete during the pulling process were analyzed. The alterations in the elastic modulus of concrete throughout the tension-failure process were thereby obtained. A method for optimizing the axial force calculation, which exploits the relationship curve between the concrete strain and elastic modulus, was put forward. This enables the accurate acquisition of the axial force of the pile body and its subsequent application in practical engineering projects. The test results indicate that under the condition of small loads, the OFDR technology can identify the locations where concrete cracks emerge based on the strain curve of the pile body. In the event of pile body failure under large loads, the elastic modulus of concrete can be rectified using the relationship curve between strain and elastic modulus. Compared with traditional calculation methods, the relative error of the axial force throughout the entire process can be confined within 5%. The viability of this approach has been corroborated in actual engineering endeavors, and the optimized axial force calculation exhibits enhanced precision.