To provide a laid sand substitute for solving the labor and unsanitary conditions of installation and maintenance of layered sand formed by spreading gravel.SOLUTION: A plurality of boll-like three bolus aggregates in which a plurality of gravel-sized blobs 1 are flexibly connected and elongated are connected to a three-dimensional structure to optimize the deformation strength of the connecting portion 2, So that a beautiful three-dimensional layout can be maintained while a predetermined gap is secured in the sand, and the bolus 1 can be used as a substitute for granules like sand which easily displaces relative to each other.BACKGROUND OF THE INVENTION【課題】砂利を敷き詰めて成る敷き砂の、設置・維持管理の手間と不衛生さを解消する、敷き砂代替物を提供する。【解決手段】複数の礫大の小塊1を屈曲自在に連結伸長した数珠状3の小塊集合体を、3次元構造につなぎ合わせ、連結部2の変形強度を最適化することで、内部に所定の空隙を確保しつつ美しい立体的レイアウトを維持することができ、かつ小塊1が容易に相対変位する粉粒体様の敷き砂代替物として使用できるようにする。【選択図】図1
