gridview is not visible when using update pannel.

<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" ChildrenAsTriggers="false" runat="server">
        <ContentTemplate>
            <asp:GridView ID="gridetails" runat="server" 

  ..... </asp:GridView>
        </ContentTemplate>
        <Triggers>
            <asp:AsyncPostBackTrigger ControlID="gridetails" EventName="Click" />
        </Triggers>
    </asp:UpdatePanel>

$(document).on("click", "#Loadqty_detl", function () {
       var dlg1=  $('<div id=DialogDiv>').dialog({
           height: $(document).height() - 100,
           width: $(document).width() - 100,
           appendTo:"form",
           closeOnEscape: true,
           autoOpen: false,
           modal: true,
           title: "Entry form",
           open: function () {
               $(this).load('Ord_Quantitydetl.aspx');
           },
           show: {
               effect: "blind",
               duration: 500
           },
           hide: {
               effect: "clip",
               duration: 1000
           },
           buttons: {
               Close: function () {
                   $(this).dialog("close");
               }
           }
       });

       var reload = dlg1.dialog("open");
       Sys.Application.add_init(reload);

   });