var arr = [{"a": "one", "b": "two", "c": "three"}];

// Frist, convert this array by JSON.parse()
var arr2 = JSON.parse(arr);

var values = [];

// Here are two methods to push values in javascript object
// One...
Object.assign(arr2, {d: "four", e: "five"});

// Two
/*arr2.d = "four";
arr2.e = "five";*/

values.push(arr2);

// The resultant array will be like this...
[{"a": "one", "b": "two", "c": "three", "d": "four", "e": "five"}]

// If there are multiple objects in basic array, then you can use WHILE or FOR loop