Apex Code:

public class a

{

     public w var {get;set}

//wrapper class

    public class w

    {

        public String str;

    }

}

Visualforce page:

<apex:outputText value="{!var.str}"/>

Regards,

Magulan D

Salesforce.com certified Force.com Developer.

SFDC Blog

If this post is your solution, kindly mark this as the solution.

thanks for your reply but i have already done this

global with sharing class DashPortalController{
public static List<CaseFailBean> listCaseFailBean{get;set;}

@RemoteAction
global static CaseFailBean[] loadCustomerServiceSuccessRate(String dateFrom){
listCaseFailBean= new List<CaseFailBean>();
CaseFailBean beanObj=new CaseFailBean(AccId,WasteColl,DaysColl,ServiceSuccessRate,ServiceFailureRate);
listCaseFailBean.add(beanObj);
}
global class CaseFailBean{
public String AccName{get;set;}
public String WasteName{get;set;}
public String DaysTotal{get;set;}
public Decimal totalCases{get;set;}
public Decimal totalServiceColl{get;set;}

public CaseFailBean(String Name,String WasteType,String TotalDays,Decimal ServiceSuccessRate,Decimal ServiceFailureRate){
this.AccName= Name;
this.WasteName= WasteType;
this.DaysTotal= TotalDays;
this.totalServiceColl=ServiceSuccessRate;
this.totalCases=ServiceFailureRate;
}

public CaseFailBean(){

}

}

==========================VisualForce Page====================
<apex:page controller="DashPortalController" readonly="true" contentType="application/vnd.ms-excel" language="en-US">
<apex:pageBlock >
<apex:pageBlockTable value="{!listCaseFailBean}" var="bl">
<apex:column headerValue="Account Name">
<apex:outputText value="{!bl.AccName}"/>
</apex:column>
<apex:column headerValue="Waste Name">
<apex:outputText value="{!bl.WasteName}"/>
</apex:column>
<apex:column headerValue="DaysTotal">
<apex:outputText value="{!bl.DaysTotal}"/>
</apex:column>
</apex:pageBlockTable>
</apex:pageBlock>
</apex:page>

the problem is, in VF page when i click export to csv then CSV file only shows Header name that i have used in 

<apex:column headerValue="">

but not showing the values