The mix design of 3D printed concrete has adopted various types of binders and additives to enhance its casting performance and shape stability. Matric suction, as an attractive force among partially unsaturated particles of the binders and additives, influences the shape stability of firm cement paste composing 3D printed concrete. Higher matric suction induces higher compressive strength (or green strength) and higher elastic modulus. The extended Mohr–Coulomb failure envelope describes the stress state of the 3D printed concrete considering its matric suction. Variation of the matric suction takes parallel shifting and rotation of the shape failure envelope. The test results on the matric suction finally confirm the effect of binders and additives. Change in the water-to-binder ratio contributes to higher matric suction related to the paralel shift of the Mohr-Coulomb failure envelope, while incorporating nanoclay or polycarboxylate ether affects the internal friction angle of the binder.

3D打印混凝土的配合比设计采用了各种类型的粘合剂和添加剂，以提高其浇注性能和形状稳定性。基质吸力作为粘合剂和添加剂的部分不饱和颗粒之间的吸引力，影响构成 3D 打印混凝土的坚固水泥浆的形状稳定性。较高的基质吸力导致较高的抗压强度（或生坯强度）和较高的弹性模量。扩展的 Mohr-Coulomb 失效包络描述了 3D 打印混凝土的应力状态，考虑到其基质吸力。基质吸力的变化需要形状破坏包络线的平行移动和旋转。基质吸力的测试结果最终证实了粘合剂和添加剂的作用。