How to structure utility class

I have several utility functions. What is the best way to package these up, and then import them?

This is what I am trying to do:

import * as util from './util'

export class myClass{
     constructor()
     {
           util.doSomething("test");
     }
}

Then in the class:

export class Util{
    doSomething(val: string){ return val;}

    doSomethingElse(val: string){ return val;}
}

The error message I get from VS is:

Property doSomething does not exist on type util.

If you create a file utils.ts which contains

export default class Utils {
    static doSomething(val: string) { return val; }
    static doSomethingElse(val: string) { return val; }
}

then you can simplify your client code like this:

import Utils from './utils'

export class MyClass {
     constructor()
     {
         Utils.doSomething("test");
     }
}