Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Contraction gradient induced microcracking in hardened cement paste
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an