concat

concat simply concatenates two arrays.

{% capture arr1 %}
[
{
"foo_1": "bar_1"
}
]
{% endcapture %}
{% assign arr1 = arr1 | parse %}
{% capture arr2 %}
[
{
"foo_2": "bar_2"
}
]
{% endcapture %}
{% assign arr2 = arr2 | parse %}
{% assign arr3 = arr1 | concat: arr2 %}
{{ arr3 | log }}

Above would log this array of json objects:

[
{
"foo_1": "bar_1"
},
{
"foo_2": "bar_2"
}
]