tax_query AND relation for same taxonomy

I have a custom post type ‘Venue’ and a custom taxonomy ‘Event Category’. I have an array that contains multiple Event Category slugs. The array can contain any number of Event Category slugs based on user input. I am trying to write a query that retrieves only those Venues that have each Event Category assigned to it that is stored in the array.
I know I need to use a tax query with the AND relation like in the following example:

$args = array(
				'post_type' 	 => 'venue',
				'posts_per_page' => -1,
				'meta_key'		 => 'venue_menu_order',
				'orderby'		 => 'meta_value_num',
				'order'			 => 'ASC',
				'tax_query'  	 => array(
					'relation' => 'AND',
						array(
							'taxonomy' => 'event_category',
							'field'    => 'slug',
							'terms'    => 'convention-without-exhibits',
						),
						array(
							'taxonomy' => 'event_category',
							'field'    => 'slug',
							'terms'    => 'convention-with-exhibits'
						),
				),
			);

The problem, however, is that I don’t want to hardcode the arrays that contain the taxonomy and term. I also know that I can’t loop through my array inside the $args array.

I did try this but it didn’t work because $tax_query is a string which doesn’t end up getting ran as php code ($event_types is the name of the array of Event Category slugs):

$tax_query ="";

		foreach($event_types as $event_type){
			$tax_query .=

			"array(
				'taxonomy' 		=> 'event_category',
				'field'    		=> 'slug',
				'terms'    =>". $event_type."
			)";
		} 

$args = array(
				'post_type' 	 => 'venue',
				'posts_per_page' => -1,
				'meta_key'		 => 'venue_menu_order',
				'orderby'		 => 'meta_value_num',
				'order'			 => 'ASC',
				'tax_query'  	 => array(
					'relation' => 'AND',
						$tax_query
				),
			);

Any help or direction will be greatly appreciated. Thanks in advance.