# Standard notation/operator to "stacking" block matrices?

I looking for some operator or compact notation to stacking vertically and horizontally several matrices (indexed and not indexed). More specifically, i want to represent in a compact way (ie, as an "inline" equation) the following block matrix:

1. $$\begin{bmatrix}A_1 & A_2 & \cdots & A_C\end{bmatrix}$$, where $$A_i$$, $$i = 1, \ldots, C$$, are matrices with the same number of rows.

2. $$\begin{bmatrix}B_1 \\ B_2 \\ \vdots \\ B_C\end{bmatrix}$$, where $$B_i$$, $$i = 1, \ldots, C$$, are matrices with the same number of columns.

3. $$\overbrace{\begin{bmatrix}I & \cdots & I\end{bmatrix}}^{\text{C times}}$$ and $$\left.\begin{bmatrix}I \\ \vdots \\ I\end{bmatrix}\right\}{\text{C times}}$$

where $$I$$ is an identity matrix.

Is there a standard notation/operator to denote those block matrices?

PS.: I have found the question Notation for juxtaposition operation on matrices, but the answer to that question is not what I looking for.

Using Kronecker products and standard basis vectors $$\{e_k\}$$ the first two cases are summations \eqalign{ A &= \sum_{k=1}^C\,e_k^T\otimes A_k \qquad\qquad B &= \sum_{k=1}^C\,e_k\otimes B_k \\ } By invoking the Einstein summation convention, one could even omit the sigmas.
The third is a special case of these with $$\:A_k=I\;\:{\rm or}\;\:B_k=I$$