Experimental Technology and Management

农林院校土木工程专业实现特色化和差异化发展具有重要意义，但农林特色最终要落实到课程建设上。土木工程材料实验是实现土木工程材料课程建设和土木工程专业建设特色化的重要抓手。该文以植生混凝土实验为例，从实验的“项目遴选-方案构建-结果与讨论”三个方面展示农林特色土木工程材料实验课程建设的思路和过程，具体介绍了植生混凝土的原材料、配合比设计、强度、孔隙率、p H值等实验项目，重点讨论了其中农林特色鲜明的关键环节，以及与现有常规实验课程的差异。最后，阐述了农林特色土木工程材料实验课程开发的意义。

[Objective] The homogenization of civil engineering experimental courses in agricultural and forestry universities impedes discipline-specific development. This study addresses this gap by constructing an innovative teaching system centered on planting concrete, an eco-functional material integrating agricultural and civil engineering principles. [Methods] This research established a tripartite pedagogical framework: project selection targeting agricultural applications(e.g., slope restoration and pollution control), scheme design emphasizing material–plant synergy, and analytical methods quantifying ecological–mechanical performance. Methodologically, low-alkali sulphoaluminate cement(LAC) was replaced with Portland cement to regulate pore pH(9.5–10.5 vs. 12.5–13.5) while enhancing early strength(54.5 MPa at 3 d, a +38% improvement). Recycled brick aggregate(RBA, 16–20 mm) with high porosity(23.6%) and water absorption(15.8% vs. natural aggregate's 2.65%) was systematically compared with natural gravel. Using skeleton density theory, an absolute volume method(Equations 1–7) optimized the mix parameters: target porosity(20%–30%), water–cement ratio(W/C: 0.30–0.36), and RBA substitution rate(0%–100%). Critical tests included compressive strength(ISO 679), porosity via hydrostatic weighing(error ≤2.3%), and pore pH measurement through solid–liquid extraction using a PHS-25 pH meter. [Results] Results revealed coupled mechanical–ecological behaviors: compressive strength peaked at W/C = 0.34(6.05 MPa) but declined by 2.64% at W/C = 0.36 due to slurry segregation. RBA substitution of >40% reduced strength by 17.4% per 20% increment, owing to its high crushing value(23.25% vs. natural aggregate's 5.7%). Porosity increased by 4.6% per 0.02 W/C rise and by 4.1% for RBA >40%, directly influencing plant root development. Pore p H decreased with higher W/C(9.6→9.1) but increased with RBA substitution(up to 3.9%) through enhanced ion migration, enabling customized plant adaptability. Educational outcomes demonstrated significant interdisciplinary competency. Students established quantitative models linking porosity(25%–30%) to root growth, undergraduates published four SCI-indexed papers and filed two patents, and 87.3% of learners showed enhanced problem-solving skills for agricultural–civil engineering challenges. [Conclusions] The course integrated ideological education by correlating material choices(e.g., RBA recycling) with national strategies like “Loess Plateau soil conservation,” resulting in 92% student endorsement of strengthened commitment to rural development. This system's three-layer architecture—foundation(conventional tests enhanced by LAC/RBA), specialization(agriculture-oriented porosity/pH modules), and extension(real-world cases like “slope restoration using RBA”)—effectively cultivates agrarian-minded engineers. Future work aims to develop virtual simulations for parameter optimization and standardize curricula across agricultural universities.