Lightweight porous composites have been widely explored to improve their acoustic and thermal performances. Hempcrete can serve as thermal insulating or soundproofing material by utilising its high porosity. However, the rigorous correlation between hempcrete thermal and acoustic performance and its pore structure remains poorly understood due to its different pore types. In this study, three hempcrete pore types [i.e., i) inter-pore between hemp and mortar, ii) hemp intra-pore, and iii) mortar intra-pore] were modified by tamping, delignification, and foaming agent conditions, respectively. Then the volumes of three types of pores were estimated using X-ray micro-computed tomography (μCT) and mercury intrusion porosimetry. The new segmentation methods were developed and their reliability and accuracy were validated. Then, the pore volumes were correlated to the thermal and acoustic properties of hempcrete. Low tamping and high delignification conditions are recommended to increase inter-pore volume and enhance hempcrete performances relating to both thermal insulation and sound absorption for real-world hempcrete applications.

中文翻译：

---

大麻和大麻混凝土孔结构的详细表征：对热和声学性能的影响


轻质多孔复合材料已被广泛探索以改善其声学和热性能。Hempcrete 可以利用其高孔隙率作为隔热或隔音材料。然而，由于其孔类型不同，大麻混凝土的热性能和声学性能与其孔隙结构之间的严格相关性仍然知之甚少。在这项研究中，三种大麻混凝土孔类型 [即 i） 大麻和砂浆之间的孔间，ii） 大麻孔内和 iii） 砂浆孔内] 分别通过夯实、脱木素和发泡剂条件进行改性。然后使用 X 射线显微计算机断层扫描 （μCT） 和汞侵入孔隙度测定法估计三种类型孔隙的体积。开发了新的分割方法，并验证了它们的可靠性和准确性。然后，孔隙体积与大麻混凝土的热和声学特性相关。建议使用低夯实和高脱木素条件，以增加孔隙体积并增强与实际大麻混凝土应用相关的隔热和吸音相关的大麻混凝土性能。